3Rd Gen Vfr750F Ninja Zx14R Rear Shock Swap

Last night I massaged a 2012 ZX14R rear shock into my 1990 RC36. I expected an easy, cheap improvement over my 25 y/o stock Showa, however, preliminary testing is proving to be far, far better than even I anticipated. It feels like the rear shock from the big Kawasaki beast was built for the early model viffer, giving it a dominant stance, and as an unforeseen bonus it breathed new life into my bone stock front end.
I originally intended to post this up only after a thorough test period (at least 1000 miles, pushing it under various conditions), but I'll save that for an update now because it looks and feels so good that I got anxious to share. So keep in mind that this experimental, and for the moment should only be attempted by those who have a basic understanding of suspension systems and those who are comfortable with simple to intermediate level modifications. I believe this could be a new serious option for those who want a "budget friendly" suspension upgrade that will provide the look, handling, and adjustability of a high-end custom shop setup. These legendary 3rd gens aren't getting any younger, and it's getting harder and harder to find decent (read: affordable) aftermarket support. Soon it will be a necessity to improvise upgrades and fixes for the whole damn bike, but that's what I really like about owning one ;) How about you?


.

Welcome to the Board. Your first post certainly knocked the ball out of the park.

I would be very interested with any follow up reports and conclusions for this mod.

I compared pics of your bike with my stock 91 I had in England using the passenger pegs as a datum and you bike seems substantially higher in the rear compared to stock. This would have decreased the trail by some amount, obviously not sure how much without measurements, but you report improved handling overall. Yes, would be very interested in further reports. All of us with older VFR's eventually will have to bite the shock "bullet" at some point if we keep our bikes and having an off the shelf option would be a great benefit.

Thanks for the kind words FM, and yes you're very observant... it's sitting around 1 inch over stock height. There's quite a few shocks that will fit well enough for a fairly easy swap, but I chose the big Ninja zx14 because I believe it most closely aligns with 3rd gen specs and performance features, they (the zx14 and the vfr750) are actually very similar geometrically. I will be testing other shocks as well, I've got an "A" list of good swap candidates, mostly newer (2008 - 2015) and readily available on eBay. There's no shortage of folks upgrading their brand new and like new super sports with the latest "high tech" aftermarket custom race offerings, thus plenty of unbelievable pickings for $50 - $150 online. Tell ya, what most of them folks don't appreciate is the fact that many of these modern "factory" rear shocks are actually better than the "custom race shocks" of the not too distant past !

Nifty

So what do you mean by 'finesse' when it comes to installation? Was it a pain to install?

No more than a half-day job for a slow and steady grease monkey, all things considered. Figure on an easy weekend for the common enthusiast who ain't skeered to go in balls deep! I will try to make an instructional video this week and post it up on YouTube. 2 simple modifications to the shock, 1 to the linkage (link mod not necessary and easily reversable but I wanted to play around with it, some folks might like it better without the link mod). My only cost was for the shock itself.

Nifty

Very interesting. Does the shock reservoir not interfere with the battery box?

And Welcome to VFRD Bill,

Jeroen.

Just took out the original one and replaced with the ZX14 shock? No machining works? How much did that raise the bike?

This looks like an interesting idea down the road. Do you plan on changing out the front shocks at some point too?

V4 Rosso

Very interesting. Does the shock reservoir not interfere with the battery box?

And Welcome to VFRD Bill,

Jeroen.

It's tight but no, battery fits fine, although I may move the starter relay over a little, not sure yet... I just uploaded a video to YouTube:

Nifty

Occse

Just took out the original one and replaced with the ZX14 shock? No machining works? How much did that raise the bike?

Just uploaded a video... more info..

snowman11

This looks like an interesting idea down the road. Do you plan on changing out the front shocks at some point too?

The forks have been maintained properly, fresh oil and seals, they suffice for the time being. I will eventually change the springs but not until after I settle on a definite rear shock, probably after another 10k miles or so..

WELCOME and I cant wait until you buy a 6th gen .

Switchblade

WELCOME and I cant wait until you buy a 6th gen .

Thanks bro, funny you mentioned that..... I was a frog's hair from jumping the trigger on a jet black 2006 a few months ago. Man that bike looked nice and the price was right.

Nifty7Fifty

[i just uploaded a video to YouTube:

I have an aftermarket shock fitted, a very basic shock, just newer and serviceable unlike the OEM shock. Curious if the S1000RR shock will fit too.

I believe the litre Beemer shock will work well. I've been following a few on eBay, will snag one soon and give it a go. After digging up all the info I needed to form a solid list of highly probable swaps, and crunching all the hieroglyphics, I'm convinced that the Zx14r (or ZZR 1400 if you prefer) is very likely the best suited candidate for the 1990 - 1993 VFR750. My conclusion is based on the specs and design parameters, engineering compatibility, and intended usage. I'll upload another video explaining why it edged out the s1000rr shock, granted that's a desktop analysis only (actual on-bike testing may prove otherwise). Here's a spoiler, I've rated the 2010 - 2011 s1000rr rear shock a close second, followed by the 2008 - 2010 Ninja zx10r coming in third place.

I'll try to post another video tonight, I need to get in the workshop and tighten up that battery tray (haven't touched it since last vid) . . .

:lurk:

:media:

Intresting and cool!

Hey Bill,

Welcome. I love what you're doing here. Unbelievable that a 21st century shock from a different manufacturer would bolt right up like that 23 years later! Awesome!

So, here's what I see. You drilled the hole in the lower linkage a little bit forward of the original one to raise the ride height a bit with the original shock. That was certainly clever. It also shortened the front end geometry a bit that would have sharpened turn in response, I'm sure. However, is it still stable at high speed? I'm getting to a point here.

It looks to me like you won't be able to use that original hole in the lower linkage because doing so would bring the reservoir into contact with the battery box. Now, if it was just barely contacting it, would that restrict swingarm travel or cause damage to the battery box and maybe the battery? Now, I wonder, is there enough adjustment in that shock to lower the ride height while leaving the lower end mounted in the new forward hole? Of course, these questions are moot if there is no loss of stability with the extra inch of ride height. If that's the case, then the biggest thing will be to aim the headlights higher! :fing02:

I'm already watching one of those shocks!

Thanks,

Glenn

This is fantastic stuff, thanks so much for posting up such a good set of videos. I've been looking for a solution to this for years.

Quick question, if i fit one of these to my rc36/1 do I have to do the dogbone bolt hole mod, or will it fit the old ones ok and still clear everything?

Many thanks again, this is excellent stuff.

Hi Bill - thanks for the info: very interesting... looking forward to seeing what mods you had to do to the shock mounts.

One question to add to everyone else's: the dog bone length reduction looks like you've reduced the length by at least 20mm or so. This surprises me - I thought (based on recent research and info from Rosso) that the ratio between dog-bone length and swingarm height / ride height was of the order of 20:1 (i.e. shorten the dog bone by 1mm you get 20mm difference in ride height).

Clearly though that can't be the case, because you used this mod with the original shock, and I presume the rear ride height didn't increase by approx. 400mm? :unsure:

Ha, in the video you mention the Ninja 636 schock. I also looked into a ninja shock: a 600 K1 model but never was able to find some good measurements of it. Just from eyeballing it looked close to a stcok 3rd gen schock.

Welcome aboard!

I am watching this with interest b/c I have a 3rd gen "in the works" and an upgraded rear shock is on my to do list for this winter.

For your next video, can you say "Fuck you Lahey"...you sound a lot like a younger version of Ricky from Trailer Park Boys!!

Also, are the ZZR shocks the same throughout the years? I've seen a 2014 one for cheap.

Hi!

thank you for sharing this with us, this is helping a lot! :D

Would this mod work with a rc36 II too?

Welcome to VFRD!

Great instructional videos and wonderful work on the rear shock swap(s).

Could you explain the exhaust setup shown in the pictures? What is the small bit attached to the collector box and does it provide any silencing?

Best regards, blackdot/Tom

blackdot

Welcome to VFRD!

Great instructional videos and wonderful work on the rear shock swap(s).

Could you explain the exhaust setup shown in the pictures? What is the small bit attached to the collector box and does it provide any silencing?

Best regards, blackdot/Tom

I'm guessing "no" :)

slovcan

Hey Bill,

Welcome. I love what you're doing here. Unbelievable that a 21st century shock from a different manufacturer would bolt right up like that 23 years later! Awesome!

So, here's what I see. You drilled the hole in the lower linkage a little bit forward of the original one to raise the ride height a bit with the original shock. That was certainly clever. It also shortened the front end geometry a bit that would have sharpened turn in response, I'm sure. However, is it still stable at high speed? I'm getting to a point here.

It looks to me like you won't be able to use that original hole in the lower linkage because doing so would bring the reservoir into contact with the battery box. Now, if it was just barely contacting it, would that restrict swingarm travel or cause damage to the battery box and maybe the battery? Now, I wonder, is there enough adjustment in that shock to lower the ride height while leaving the lower end mounted in the new forward hole? Of course, these questions are moot if there is no loss of stability with the extra inch of ride height. If that's the case, then the biggest thing will be to aim the headlights higher! :fing02:

I'm already watching one of those shocks!

Thanks,

Glenn

Hi Glenn, those are excellent questions, I love to see folks thinking! That bike is a high speed MONSTER, I routinely touch 150 mph, with acceptable stability and handling. Now that was with the original shock, mind you, and there are numerous reasons why the bike handled the way it did. I will post up more about that later. The ride height with the 2nd hole drilled in the bone, is about 1.5 - 2 inches (or 40 - 50 mm) over stock height, with the original VFR rear shock installed. With the ZZR-1400 rear shock I'm now approximately 1 - 1.5 inches (25 - 35 mm) over stock height, linked into the 2nd hole. The new height feels much better, although the new rear end would probably feel much better at any height :) You could definitely use the original hole in the dog link without any adverse contact (actually, it would prob fit better). I will do a video explaining this more thoroughly (think geometrically, pivot (swing) points, also the range of motion of the link (direction). Your question on lowering the shock; there's a bit it will go, one way or the other, but to address your real question, yes the handling is superb at that height. Now that does not mean it's for everyone, it does get a bit top heavy so one needs to adapt their riding accordingly. Anyone under 5'10" or lightweight individuals would struggle with the bike at that height (unless you put some motocross forks on it)

.

Marc87

Hi!

thank you for sharing this with us, this is helping a lot! :D

Would this mod work with a rc36 II too?

Hi, glad you're enjoying the thread. The Zx-14r shock is not easily compatible with the 4th gens, it would require more comprehensive modifications. There are other options for the 4th gens though.

·

Y282

This is fantastic stuff, thanks so much for posting up such a good set of videos. I've been looking for a solution to this for years.

Quick question, if i fit one of these to my rc36/1 do I have to do the dogbone bolt hole mod, or will it fit the old ones ok and still clear everything?

Many thanks again, this is excellent stuff.

It will fit fine in the original link hole, but you might be anywhere from 5 to 13mm lower ride height. Some folks like a little lower, it's totally subjective based on your size and riding preference. Drilling the link is not necessary for this swap, the 2nd hole is merely for lifting the rear.

.

https://youtu.be/9MdC_0lpyCc

Rice

Welcome aboard!

I am watching this with interest b/c I have a 3rd gen "in the works" and an upgraded rear shock is on my to do list for this winter.

johnlondon

For your next video, can you say "Fuck you Lahey"...you sound a lot like a younger version of Ricky from Trailer Park Boys!!Also, are the ZZR shocks the same throughout the years? I've seen a 2014 one for cheap.

If nobody has already pointed this out, the ZX-14R rear shock (2012) has a spring rate of 9.7kg/mm

The VFR750 shock (1990-93) has a spring rate of 16 kg/mm

This is a HUGE difference, and should not be ignored.

You could lever on a stiffer spring to the ZX-14 shock, but then it would be severely underdamped for that spring.

Good point the spring rate, but how does the change in linkage effect to what spring rate is needed?

But yes, in the vid the rear seems soft even controlled, use meay mutch of its travel, so might work solo but 2 up I think this setup will not work, will easy bottom out.

Just my 2 cent

Veefer800Canuck

If nobody has already pointed this out, the ZX-14R rear shock (2012) has a spring rate of 9.7kg/mm

The VFR750 shock (1990-93) has a spring rate of 16 kg/mm

This is a HUGE difference, and should not be ignored.

You could lever on a stiffer spring to the ZX-14 shock, but then it would be severely underdamped for that spring.

Thanks for bringing this up! They are completely different shock designs, like comparing apples to watermelons. You wouldn't want to go heavier on the ZZR spring unless you are heavier than 225 lbs (in my opinion), as a matter of fact, one of the reasons I chose the ZZR shock was for it's 9.7kg spring (one of the heavier modern factory offerings). These are modern devices utilizing spring manufacturing and tech that wasn't around in late 80's/early 90's. No doubt the 16kg spring on the viffer was likely used to overcompensate for the dogshit damping unit ;) I'm at 210 - 215 with gear and I still have about 30% more thread left to tighten the preload down harder on the new ZX, but it feels perfect where it's at. I'm sure a "custom" suspension guru could "dial in" the perfect spring and "tune" the shock a little more to get the most out of it, but this was meant to be a cheap and easy way to get your old viffer back up to speed. And so far, I'm very impressed. Bet if you took it for a spin, you'd agree that it's much better than when it came off the line in 1990. Now I'm no guru at all, but I've never even heard of any modern racers using a 16kg spring? By the way, the Ninja 1400 is 580 lbs. wet, I think the viffer is what 540? This is another reason the Zx14r rear shock is a powerful choice. It's widely known, that the Kawasaki zx14r handles like a Sports-Tourer rather then a super-sport.... These are just some of the dots I connected to reach the conclusion that the big Ninja shock would be a prime choice. Now that I'm well past all the speculation and into real-world testing, I can tell you it's truly better than I anticipated, Can't wait to hit the highway and really see what she's got ;)

.

keny

Good point the spring rate, but how does the change in linkage effect to what spring rate is needed?

Can't use the original spring rate as a gauge, it's obsolete technology... You are right on track with bringing up the linkage though, that is a big piece of the puzzle. Check out the reply I just left for Veefer800Canuck. . .

Brilliant, thanks for the third vid. Can't believe how stock it looks in situ.

Look forward to the info about modding the mounts, then i'm 100% doing this to mine.

How much stiffer can you make the shock perform than the setup in your third vid?

Y282

Brilliant, thanks for the third vid. Can't believe how stock it looks in situ.

Look forward to the info about modding the mounts, then i'm 100% doing this to mine.

How much stiffer can you make the shock perform than the setup in your third vid?

There's quite a bit of preload adjustment left, I'd say I'm only 60 - 70% down on the preload (there's approximately 30% thread left to tighten down). Keep in mind on that last video I was standing behind the bike, pushing down on the grab-holds with all my strength. At that angle and thrust, it produces an unusual and unnatural strain to the suspension. I did this to simulate extreme suspension compression and range of motion, to confirm that there was no binding or contact anywhere, which as seen in the video there was none. During test riding, however, the rear end was firm, and the damping was extraordinary. The test roads are very bumpy and twisty, with patches of gravel and potholes around every corner (typical NorthEast American back roads), And I could not feel anything at all from the back, It absorbed every bump, crack and dip, without the slightest wheel slip or bounce, all while feeling planted through every turn and under hard acceleration. It really is unbelievable, maybe because I was accustomed to the original shock, which only really had 2 settings - Pogo stick or Cadillac mode.

.

Awesome, cheers.

I'm getting a 2012 one off ebay for 85 quid (not sure what that is in dollars).

Y282

Awesome, cheers.

I'm getting a 2012 one off ebay for 85 quid (not sure what that is in dollars).

.... that's about $130 USD. Looking forward to seeing your results! You could be part of the multinational elite team of people that own a Viffer tricked out with a ZX14R shock!! (right now the Worlwide Super-Elite Ninja VFR750 team is just me, lol)

Dead excited for it. The vfr is my go to bike for bad weather, commuting, etc so i don't mess up any other bikes but tbh i enjoy riding it so much i tend to take it out anyway. the rear shock has always bugged me on an otherwise really well built bike.

Update: Bought it!

(christ this better work)

"The Zx-14r shock is not easily compatible with the 4th gens, it would require more comprehensive modifications. There are other options for the 4th gens though." So, other than the 929 shock, what might some of these other options? Said the 4th gen owner with almost 35,000 miles on the stock shock.

Y282

Dead excited for it. The vfr is my go to bike for bad weather, commuting, etc so i don't mess up any other bikes but tbh i enjoy riding it so much i tend to take it out anyway. the rear shock has always bugged me on an otherwise really well built bike.

Update: Bought it!

(christ this better work)

Congrats bro! Welcome to the Ninja Viffer club !! (You automatically upgrade to "Worldwide Super-Elite" status after a successful installation ;D

Guess this means I really need to get moving on the "official" How-To video. . .

Let me be REAL clear about this; To the fellas who thought the suspension looked soft in the video, it's called leverage. I stood behind the bike and pushed down on the rear sub-frame with all my might (I'm 6' 200 lbs. muscular build). I can generate alot of force, and I did. And no, it did not bottom out... Not even close, nor a little bit. Nowhere near bottoming out. Proof is right there on the video, I hold no punches. That's why I performed that test, because I too wanted to be sure that it would go the extreme, which it did. Now, I can assure you, when you ride you will come nowhere near the amount of pressure I used on that video, not by yourself or 2-up. Unless of course, you are 300 lbs. and are accompanied by a 200 lb pillion (in that case, I would just get a GoldWing).

2 Important points: When test riding, the rear proved to be rock solid, and dampened everything I threw at it to boot. Make no mistake, these roads are terrible out here, but perfect for a shake-down run. And secondly, as I previously mentioned, I set the preload on the softer side, especially for my size. There is a good bit of room left to really tighten down that preload. So if you wanna feel like you're riding on the frame, go ahead, crank that baby down.

Fellas, let's understand something now before your speculation confuses someone....

Ready...

Here it comes....

I completed the swap already! I'm in the Road-Testing phase now. So far, it's been flawless !! You can not argue with RESULTS !!!

By the way, don't take this post the wrong way, no offense meant. I'm a go-getter, I get things done. I'm not interested in all the assumptions and negative speculation, I make SOLUTIONS.

Thanks

Nifty7Fifty

Y282

Dead excited for it. The vfr is my go to bike for bad weather, commuting, etc so i don't mess up any other bikes but tbh i enjoy riding it so much i tend to take it out anyway. the rear shock has always bugged me on an otherwise really well built bike.

Update: Bought it!

(christ this better work)

Congrats bro! Welcome to the Ninja Viffer club !! (You automatically upgrade to "Worldwide Super-Elite" status after a successful installation ;D

Guess this means I really need to get moving on the "official" How-To video. . .

Think the only thing i don't know now is about the mounting mods you mentioned, everything else is good. This looks like a very practical solution.

Nifty7Fifty

Let me be REAL clear about this; To the fellas who thought the suspension looked soft in the video, it's called leverage. I stood behind the bike and pushed down on the rear sub-frame with all my might (I'm 6' 200 lbs. muscular build). I can generate alot of force, and I did. And no, it did not bottom out... Not even close, nor a little bit. Nowhere near bottoming out. Proof is right there on the video, I hold no punches. That's why I performed that test, because I too wanted to be sure that it would go the extreme, which it did. Now, I can assure you, when you ride you will come nowhere near the amount of pressure I used on that video, not by yourself or 2-up. Unless of course, you are 300 lbs. and are accompanied by a 200 lb pillion (in that case, I would just get a GoldWing).

2 Important points: When test riding, the rear proved to be rock solid, and dampened everything I threw at it to boot. Make no mistake, these roads are terrible out here, but perfect for a shake-down run. And secondly, as I previously mentioned, I set the preload on the softer side, especially for my size. There is a good bit of room left to really tighten down that preload. So if you wanna feel like you're riding on the frame, go ahead, crank that baby down.

Fellas, let's understand something now before your speculation confuses someone....

Ready...

Here it comes....

I completed the swap already! I'm in the Road-Testing phase now. So far, it's been flawless !! You can not argue with RESULTS !!!

By the way, don't take this post the wrong way, no offense meant. I'm a go-getter, I get things done. I'm not interested in all the assumptions and negative speculation, I make SOLUTIONS.

Thanks

Ah, perfect!

We're about the same size - I love it when someone does all the research for me. Thanks again for sharing this.

And yeah - We should go for a ride one of these days. Or maybe have a wrench day and swap lies stories :beer:

P.S.

You didn't buy stock in manufacturing of used ZX shocks, did you? :laugh:

Nifty7Fifty

Can't use the original spring rate as a gauge, it's obsolete technology...

I have a friend that has a old early 80´s Z1000 that he has put a 3rd gen swing arm on. As a shock he did use a ZXR750 (ZX7) H1 Öhlins shock that he had around, but did find it had a to soft spring when he actually did ride it. Even you add preload to a point where sag is ok, when you ride it hard on roads whit fast altitude changes, and then still talking moderate altitude changes, the shock bottoms out fairly easy for him. I dont recall what spring rate the H1 has, but its softer than the stock Honda I know. Anyway a to soft spring is as dangerous as a to stiff, as a bottomed out suspension is like no suspension and take the bike out of control.

What you test is interesting, yes, but I agree whit V4Rosso that the shock looks soft in the vid, that compare if I would do same whit my 3rd gen that has a healty OEM shock. Its just impossible to give same load on the bike by hand that a real force by actually ride does to it. A soft suspension feels nice to a point, then its getting bad.

Just measured sag... dead ballz on 19mm. Plus the preload has a way to go. I appreciate your opinions,I know you guys are checking all the bases. I'm telling ya though, you are far off base with the spring rates. The spring material is only one (small) factor. This is a modern cutting edge damping unit. You need to focus on the unit as a whole. Just zeroing in on the spring, does nothing. The spring is a bigger factor in older units with crap internals. I build custom off-road 4wd truck suspensions also, and the damping technology is so advanced now, that some guys run their trucks with no springs at all [this is just an example of how far the tech has come in just the last ten years, and that would be an ultra high end damper] Likewise, these [zx14r] shocks are top of the line, advanced units, engineered by Kayaba. That being said, I am still testing, but I'm giving it to you straight, in real time. I have no dogs in this fight... if there were any probs, I would not hesitate to point them out. It's nothing for me to yank this shock out and throw in the next one on my list. I welcome anyone on this forum to visit me, and come take the ninja viffer for a joyride and see for yourself!

By the way Russo, a 22kg spring? Holy shyt chap !?! Can't comment on your setup, good deal if it works for you bro. All I can say is I'm 200lbs naked and so far the Zx Viffer is hauling me like nobody's business ;)

Nifty7Fifty

Just measured sag... dead ballz on 19mm. Plus the preload has a way to go. I appreciate your opinions,I know you guys are checking all the bases. I'm telling ya though, you are far off base with the spring rates. The spring material is only one (small) factor. This is a modern cutting edge damping unit. You need to focus on the unit as a whole. Just zeroing in on the spring, does nothing. The spring is a bigger factor in older units with crap internals. I build custom off-road 4wd truck suspensions also, and the damping technology is so advanced now, that some guys run their trucks with no springs at all [this is just an example of how far the tech has come in just the last ten years, and that would be an ultra high end damper] Likewise, these [zx14r] shocks are top of the line, advanced units, engineered by Kayaba. That being said, I am still testing, but I'm giving it to you straight, in real time. I have no dogs in this fight... if there were any probs, I would not hesitate to point them out. It's nothing for me to yank this shock out and throw in the next one on my list. I welcome anyone on this forum to visit me, and come take the ninja viffer for a joyride and see for yourself!

By the way Russo, a 22kg spring? Holy shyt chap !?! Can't comment on your setup, good deal if it works for you bro. All I can say is I'm 200lbs naked and so far the Zx Viffer is hauling me like nobody's business ;)

OK, here's a couple of more thoughts as the analysis continues. For sure 21st century damping may somehow offset the need for a higher spring rate. To my mind that would mean the damper is now expected to carry some load previously carried by the spring. Maybe. You say some offroad suspensions do without springs. Wow. Those must be some strong shock bodies and seals!

In this case, well, new tech vs old tech, I'm sure the actual linkage design has the most impact on the required spring rate. How similar is the Kawasaki linkage design to our old VFRs? Following this train of thought, maybe drilling a new mounting point on the dogbone has significantly reduced the leverage of the swingarm on the shock/spring thus allowing a lower rate spring to perform well. Bill, how would you feel about a comparison using the original dogbone mounting hole?

Taking this a step further, how hard would it be to change out the ZX14 spring with one from a Connie14, for example? Of course, finding a Connie14 spring without having to buy the whole shock assembly might be next to impossible. But, if we had the unladen spring length (off the shock) and inside diameter, we could maybe find stiffer suitable replacements for those of us who might want that.

Loving this, thanks!

Cheers,

Glenn

There is still one major factor that nobody's mentioned yet.. waiting to see which one of you blokes figures it out first. I want to see how much thought you're really putting into this ;)

Glenn - I would just order an ohlins spring, best bang for the buck imo...

Nifty7Fifty

There is still one major factor that nobody's mentioned yet.. waiting to see which one of you blokes figures it out first. I want to see how much thought you're really putting into this ;)

Glenn - I would just order an ohlins spring, best bang for the buck imo...

??? I fear you may not have understood the tone and context of what I wrote. Like I said, just thoughts. Before you discovered this solution, a fellow called Raymond from Houston on the V4Hondabbs site was modding CBR600 shocks for us to put on our V65 Sabres. I put one on mine and loved it. It felt a lot softer than the old air/oil set-up, but performed great. It did have to be set at near max everything, but those adjustments were there and it worked.

My curiosity was about how it would feel with the original dogbone mounting hole to preserve the original front end geometry. Actually, this won't work, as I think that would give it a lower ride height and may make it too soft. Still, there may be a spot between the original hole and where you drilled yours that would give the same ride height as stock and, maybe if that was too soft for some, a spring change would solve that.

I'm game to give your set-up a go as it is. Sharper handling and steering in 90+% of my riding. I don't really care that much about 150 mph stability (which you said was OK anyway with the original shock and increased ride height) because I never go anywhere near that fast.

Edit: I just found this on eBay. The listing has an interesting chart at the bottom. http://www.ebay.com/itm/Kawasaki-ZX-14-Heavy-Duty-Shock-Spring-/171924930441?hash=item2807863f89:g:XW4AAOSw-nZTpjdF&vxp=mtr

Just more food for thought.

Cheers,

Glenn

Hey Glenn... ok got you, on the road at the moment, missed the part about the bracket hole position. Good question, I really wouldn't expect a big difference, minor maybe. Keep in mind I'm only 2/3 down on all 3 device settings, so plenty of room left to counteract the change in geometry (I reckon). If I dropped back to the original dogbone position, I would lower the front proportionately. That brings up another point, part of the reason why the suspension moves more fluently now is due to the rear being better coordinated with the front forks, moving as one complete system. The original suspension always felt like 2 separate systems to me (front & rear). Now the bike moves the way it should, synergistically. The ZZR shock (as tuned) definitely compliments the forks. I'd be concerned about swapping out the spring and losing some of that synergy. I'm looking forward to more folks having fun with this swap and seeing some variations on the setup!

*** Nice job finding that chart :fing02: It correlates everything I've been saying! That particular chart is based on extended swingarms... now study those recommended spring rates and their associated values (riders weight & SA length, i.e. LEVERAGE).
The 16kg spring is the HEAVIEST offering on the chart, recommended only for 250+ pound riders running a 14 INCH EXTENDED swing arm!!! WHOA. And someone on here was talking about running a 16kg spring on their stock viffer :laughing6-hehe: Too Funny. Hope everyone has a chance to look at that chart.

.

Well, you are right about leverage but that chart has nothing to do with it in this case. Picking a new spring for an extended swingarm is simple math, the link system used on both the ZX and the Honda is a bit more complex and the link ratio between the ZX and the VFR will be far apart judging by the different stock spring rates. This animation illustrates the moving parts involved very well.

[image: 2004_honda_cb1000_upl.gif]

The geomtry and the way the different part connect (and move) between the ZX and VFR differ quiet substantialy. Do you know the stroke of the ZX shock? As it has only a 9,7kg/mm spring I guess it has a longer stroke than the VFR shock. I would not be surprised if the rear wheel now has so much travel that it can hit the undertray before the shock bottoms out. Haven another person (your size and strength )push hard down on the rear grab handles while you are seated on the bike.

[image: ZX14.png]

ZX14 link system

[image: vfr.png]

VFR750 link system.

[image: vfr.jpg]

VFR750 shock arm

Here is some background info on the subject: http://www.promecha.com.au/leverage_linkages.htm

Nifty7Fifty

And someone on here was talking about running a 16kg spring on their stock viffer :laughing6-hehe: Too Funny.

ugh, forums. Full of armchair experts.

He's out there, riding the bike, hasn't fallen off, hasn't bottomed out, he's got nothing to prove.

Stick one on your bikes THEN have an opinion on it.

V4 Rosso

Nifty7Fifty

Too funny

You'd have to talk to Honda about that as 16kg/mm is about the stock spring rate.

-Exactly... The "stock" spring rate... On the the stock shock that Honda says is obsolete. You know, that same dog poop shock that Honda stopped supporting a long time ago? The shock that everyone hates, the one major flaw on an almost perfect bike.

Here's a little history; Honda knew the rear suspension was garbage, so much so, that they delayed delivery of the first 3rd gens to the USA for over 6 months while they "worked the bugs out" [of the suspension]. They never did get it right, but it handled good enough to sell...

On another note... Glad to see you're thinking :woohoo: I was wondering when someone would finally add stroke to the equation. Yes stroke has alot to do with it, and all the aforementioned factors (geometry, stroke, spring rate, etc.) all work together, and must be understood as a whole. My bike is now handling the way it should have when it was fresh off the showroom floor. New setup is infinitely better than stock, you just gotta run the piss out of it and see for yourself.

I don't see it bottoming out, doesn't even come close, but I will sit on it and have a friend try as you suggested. If one were truly concerned about bottoming, you could simply raise the bumpstop - done deal. However, The longer stroke makes for a more precise (and smoother) range of motion. It feels like it's allowing the swingarm to function more proper, like how it was designed to move. I believe the longer stroke gets the most out of it.

.

Welcome Bill and helluva first post but judging from your pic in original post there is no way you are 6' and 210 lbs...

No, I am afraid it is not able to bottom out and that makes it potentially dangerous. And yes, the consus here on VFRD is that the stock shock is poor as it is considered undersprung and overdamped. I don't know bout the introduction of the 3rd gen being delayed and/or what American Honda changed to the rear suspension, only that worldwide it did get a new shock with rebound adjustment on the '92 model.

@johnlondon: He has taken it for a spin around the block, right Bill?

LangoPTC

Welcome Bill and helluva first post but judging from your pic in original post there is no way you are 6' and 210 lbs...

LOL ....before I fell over laughing, I was actually scratching my head because I didn't remember posting a pic of myself !!

Thanks for the humor man !! This post needed a laugh :beer:

V4 Rosso

@johnlondon: He has taken it for a spin around the block, right Bill?

"around the the block" is an expression in 'Murica ...15 miles of twisty, dippy, bumpy, country roads so far buddy, to be exact. (not much, but plenty for a proper shake-down run) I need to get the lights and fairings back on before I take it out on the freeway and get it up over 120, but not gonna happen yet because I've got more things to do before I put her back together... Listen, I am rough on all my stuff, especially the bikes. I push shit to the limits. 15 miles (so far) is more than enough to see what this things made of. I don't know how you chaps do it over there, but in 'Murica we lane split over 60mph... often... through freeway traffic. I'm no slouch dude. Not a keyboard commando, and I welcome anyone to come ride with me.

V4 Rosso

No, I am afraid it is not able to bottom out and that makes it potentially dangerous.

Okay dude, now you're just bustin' my chops, I got nothing. Read my reply before you post please... I mentioned already, that if you're skeered about that then all you need to do is raise the bumpstop.

So Bill, you have been out on a 15 mile leg on public road whit out any lights on the bike? :unsure:

keny

So Bill, you have been out on a 15 mile leg on public road whit out any lights on the bike? :unsure:

You gonna lecture me now?

What the hell's this turning into?

Guy's given you some pretty good info based on a fair bit of research and shot three long videos showing how to do the work. If anyone doesn't want to, then don't.

I've ordered the shock and will be doing mine over the xmas period (cleaning and refitting my rrn first) but from what i've seen this looks a huge improvement over the bloody woeful shock the 36/1 came equipped with.

Tell ya what fellas, you can have this post, I'm turning over the keys.. Go ahead, enlighten everyone with your infinite wisdom.

I've done my job, shared an idea and my results. Time to step back and see where she goes. I'll leave it up to the new Ninja Viffers to share their experiences and results.

For anyone who would like the play-by-play, I will upload a step-by-step vid detailing the simple procedure. So look out for that.

:wheel:

Nifty7Fifty

keny

So Bill, you have been out on a 15 mile leg on public road whit out any lights on the bike? :unsure:

You gonna lecture me now?

No, but just tells me a thing or two.

Just good luck whit the project.............................................

Nifty7Fifty

LangoPTC

Welcome Bill and helluva first post but judging from your pic in original post there is no way you are 6' and 210 lbs...

LOL ....before I fell over laughing, I was actually scratching my head because I didn't remember posting a pic of myself !!

Thanks for the humor man !! This post needed a laugh :beer:

And a hair cut . :goofy:

Hey Bill,

THANK YOU for doing this mod and presenting us with the detailed info. Yes, there are naysayers on the forum. Fuck 'em. This isn't about engineering a new race bike, but modding a new part onto an old bike with GREAT results - maybe the cleanest, easiest and most impressive mod yet.

I'm in. Now, before you sit too far back, can you take some time to show us what you did with the shock mount so we can get on with it, please?

Cheers,

Glenn

Nifty7Fifty

"around the the block" is an expression in 'Murica ...15 miles of twisty, dippy, bumpy, country roads so far buddy, to be exact.

What's with all the negative comments all of a sudden? Oh well, good luck with it.

I am going to put one of'em ZX shocks on my bike and report to y'all as soon as I get the bike on the road.

To all who doubt, we can debate this until the cows come home, but it's only a matter of $100 and some tinkering to find out for sure.

Thank you so much for your detailed write-ups and videos. Very well done.

Now, can you recommend a shock to swap into a '97 VFR750F?

..blackdot/Tom

You know, this is why I swerve these forums a lot. The VFR fraternity seems to be full of negative, self righteous types who have read a few bits here and there, put little into practice but are self confirmed experts on whatever subject matter comes up. You can't even get a straight answer on a front end swap around here as MOST HAVEN'T EVEN ATTEMPTED IT, yet most speak of it as if they're experts.

This guy has done some tinkering, had some great results and has shared it with you all (in enough detail for you to go outside and do this mod right now).

Also, riding without lights? Really? Are people going to have a go at that? It's his bike, his life, it's not a legality to have lights on during the day as far as I'm aware?

Can an admin purge all the nonsense that's been added in here so those of us with genuine interest (and no over inflated opinions) can have a proper good read and make sense of it all without having to sift through the armchair opinions?

Nifty, like other, I'm very thankful for you for typing all this up and making the videos, you didn't have to do it at all. Hope the shock works out perfect for you and I hope to see you upping some more ideas around here as they're always welcome as far as I'm concerned.

Thank you, Bill. That was the last piece of the puzzle - and a pretty small piece having seen it. When I do mine, I'll measure the thickness of each ear (side) of the lower mount with a caliper and subtract 1mm to get the new target thickness - just to avoid taking 1.1mm off one side and 0.9mm off the other. You're right, beveled edges and corners give the finished product a professional touch.

For the top, the collar (or bushing) doesn't slide out? If so, you could clamp it in soft jaws to give easier access for filing/grinding.

Cheers,

Glenn

blackdot

Thank you so much for your detailed write-ups and videos. Very well done.

Now, can you recommend a shock to swap into a '97 VFR750F?

..blackdot/Tom

I sure can, but I would need to take a look at a 4th gen bike in person, or at the very least if someone could send me an old shock that they no longer need. . . otherwise I could probably throw some ideas out there, but it would just be an educated guess without actually having a 97' shock in hand to evaluate..

johnlondon

You know, this is why I swerve these forums a lot. The VFR fraternity seems to be full of negative, self righteous types who have read a few bits here and there, put little into practice but are self confirmed experts on whatever subject matter comes up. You can't even get a straight answer on a front end swap around here as MOST HAVEN'T EVEN ATTEMPTED IT, yet most speak of it as if they're experts.

This guy has done some tinkering, had some great results and has shared it with you all (in enough detail for you to go outside and do this mod right now).

Also, riding without lights? Really? Are people going to have a go at that? It's his bike, his life, it's not a legality to have lights on during the day as far as I'm aware?

Can an admin purge all the nonsense that's been added in here so those of us with genuine interest (and no over inflated opinions) can have a proper good read and make sense of it all without having to sift through the armchair opinions?

Nifty, like other, I'm very thankful for you for typing all this up and making the videos, you didn't have to do it at all. Hope the shock works out perfect for you and I hope to see you upping some more ideas around here as they're always welcome as far as I'm concerned.

Thanks for keeping it solid, bruv :fing02: Love the YouTube channel by the way, subbed you a couple days ago :musik20:

.

slovcan

When I do mine, I'll measure the thickness of each ear (side) of the lower mount with a caliper and subtract 1mm to get the new target thickness - just to avoid taking 1.1mm off one side and 0.9mm off the other.

Brilliant, Glenn !! Wish you posted this earlier, I would've included it in the video! I just eyed it up, but your suggestion takes out the human error, a necessity especially for anyone who is just getting their feet wet with this.

-----The top collar doesn't slide out, it's married to the rubber buffer. The top end is mostly a non-moving part, the rubber is in their to buffer the vibrations. (no needle bearings or anything like that)

So this arrived today...

[image: post-30385-0-40670200-1446581258.jpg]

[image: post-30385-0-26083200-1446581270.jpg]

And will be going on this...

[image: post-30385-0-72696400-1446581370.jpg]

Y282

So this arrived today...

[image: attachicon.gif]image.jpg

Congratulations! Mine should be here in a week - 2015 model with 1500 kms on it!

I'm thinking about looking for a dogbone to try drilling a hole a bit closer to the original one than Bill's location. Maybe, maybe not. I'm thinking that might let it sit at the original ride height, but maybe resulting in it being too soft. OK, I just talked myself out of it. Thanks.

Cheers,

Glenn

Y282

And will be going on this...

[image: attachicon.gif]image.jpg

Man, that sure is a beautiful specimen. 3rd gen hot sex right there, money. Wish we could get those bubble screens in 'Murica . . .

Rice

We're about the same size - I love it when someone does all the research for me. Thanks again for sharing this.

And yeah - We should go for a ride one of these days. Or maybe have a wrench day and swap lies stories :beer:

Sorry, missed this post the other day, Sounds good bro!

Nifty7Fifty

Y282

And will be going on this...[image: attachicon.gif]image.jpg

Man, that sure is a beautiful specimen. 3rd gen hot sex right there, money. Wish we could get those bubble screens in 'Murica . . .

Cheers, it was a bit knackered when i bought it. I ran it with the original screen for a bit (got one with the reddish tint) but this has much better cover. It's funny, i bought the vfr to use as an all weather rough bike to keep my blade clean and i've ended up pampering it a bit. Just love riding it.

slovcan

Y282

So this arrived today...[image: attachicon.gif]image.jpg

Congratulations! Mine should be here in a week - 2015 model with 1500 kms on it!

I'm thinking about looking for a dogbone to try drilling a hole a bit closer to the original one than Bill's location. Maybe, maybe not. I'm thinking that might let it sit at the original ride height, but maybe resulting in it being too soft. OK, I just talked myself out of it. Thanks.

Cheers,

Glenn

I'm goint to run it on the original dogbone setting to start with. It's an easy adjustment if i need to jack it up later, but i already pulled the forks through by a good inch, so it might make it overtight on turn in.

Nifty7Fifty

Rice

We're about the same size - I love it when someone does all the research for me. Thanks again for sharing this.

And yeah - We should go for a ride one of these days. Or maybe have a wrench day and swap lies stories :beer:

Sorry, missed this post the other day, Sounds good bro!

If you want me to get you one and send it over (all at cost) let me know, they're plentiful over here in the UK. Here's mine

[image: IMAG1620_zpssgl51yj9.jpg]

[image: IMAG0706_zpsrtkfgcsb.jpg]

I would very much like one

Sent from my XT1254 using Tapatalk

Very interesting thread.

I'm curious how the 9.7 kg/mm spring will behave on the stock linkage. Not trying to be a naysayer but that shock has much more travel and a much lighter spring than stock so I'd think the dogbone mod is a must ...

Speaking of shocks for the 4th Gens., the Aprilia RSV Mille's (that's Mille, not the '04-on RSV1000R) unit fits pretty well in terms of having the right length and the correct mounting points (10 mm 'eye' on both ends rather than the 3rd Gen's clevis at the bottom). I have yet to try it on the bike so I don't know if or how much the (rather large) reservoir fouls the battery box and how accessible the rebound and preload adjusters will be. Got the shock for a song so the tinkerer in me could not resist. Besides, its colours make it look like an Öhlins to the casual observer which the snob in me could not resist. :laugh2:

Incidentally, it happens to come with a (way lighter than stock) 95 N/mm spring just like the ZX14.

- Due to the keen interest from the real men on this forum, I've decided to continue supporting this post with performance updates, and by answering questions from those of you who are actively performing this swap.

- This is the last thing I'm going to say to the "gurus" . . . I understand all of the geometric hieroglyphics that you throw out there. Honestly, I really do, I'm one of those "weird" people who actually enjoys math. However, there is a point where common sense trumps all that crap. The ZX14r rear shock was engineered for the fastest production bike in the world (Kaw H2 notwithstanding). The ZZR1400 is alot heavier (590lbs.) and vastly more powerful (twice the HP & torque) than an RC36. All of it's components are engineered to withstand the forces generated by all of that raw power, and you keyboard mechanics actually think the shock is not good enough for your 1990's 750 class sport bike?? RFLMBO :laughing6-hehe: :laughing6-hehe: :laughing6-hehe:

That's a good one, ok I'm done now.... wait.. here's another... Why don't you give Kawasaki's engineering dept a call, Tell them you think the rear shock on their crown jewel rocket ship is "too soft" for your 25 y/o sport-cruiser :tour:

Alright, back to business... I've put some more miles on the Ninja Viffer this week, took a couple notes, and shot a video with my camera mounted to the bike demonstrating suspension movement under various conditions; Hard accelerating, braking, fast riding and cornering on very bumpy, dippy roads. Will upload soon, be on the lookout . . .

.

johnlondon

Nifty7Fifty

Rice

We're about the same size - I love it when someone does all the research for me. Thanks again for sharing this.

And yeah - We should go for a ride one of these days. Or maybe have a wrench day and swap lies stories :beer:

Sorry, missed this post the other day, Sounds good bro!

If you want me to get you one and send it over (all at cost) let me know, they're plentiful over here in the UK. Here's mine

[image: IMAG1620_zpssgl51yj9.jpg]

[image: IMAG0706_zpsrtkfgcsb.jpg]

Love the look of this one, left exhaust and clear indicators. Really wanted a set of the indis but theyre bloody expensive.

Worth the outlay mate, do it.

Custom bits on my bike (sorry for the hijack nifty!):

Respray with gold flake

Shorty levers

Maxton front end

Penske rear shock

Full Sebring left exit exhaust

Clear indicators

Double bubble

Mirrors (now have different from pics, with integrated indicators)

OSRAM bulbs

Custom tank badge

Custom fairing stickers

Michelin PR4's (great tyre!)

I've got the final touches to add:

Brembo calipers from a Ducati 900ss (just need to find a suitable 16mm master cylinder if anyone has suggestions)

Braided lines for those Brembos, clutch and rear brake as well

Retrimmed Corbin seat

Then I'll just be riding the piss out of it as it doesn't get enough use. I have a battered 1990 with knackered fairings for commuting into London.

Anyway, Nifty....good to read you're continuing with this, forget the naysayers...there'll always be "expert" critics who quote some shit they've read in a post by someone they don't know who also put that post in place to basically quote someone they don't know...all while having tried approximately jack shit to confirm said "expertise". Sounds like you know your stuff and the rest of us are keen to hear more!

Y282

I'm goint to run it on the original dogbone setting to start with. It's an easy adjustment if i need to jack it up later, but i already pulled the forks through by a good inch, so it might make it overtight on turn in.

If your front end is already lowered an inch, then you should be sitting pretty with the new rear shock and the original dogbone hole. Your rake will probably be closer to factory spec again. Remember, the reason we raised our rears and/or lowered our fronts in the first place, was to offset the [lack of] rear damping. With a proper shock on the back end, the stock rake angle should feel perfect.

johnlondon

Custom bits on my bike (sorry for the hijack nifty!):

All good buddy, I was curious what you had in it too !! Looks AWESOME, the clear turns go perfect with the white paint. The tank badge is tight, really sets it off.

johnlondon

If you want me to get you one and send it over (all at cost) let me know, they're plentiful over here in the UK. Here's mine

Right on, good lookin out bruv, I might have to take you up on that soon! I just got this short dark tinted one in from China. . .

[image: post-34030-0-12357800-1446614527.jpg]

I'm upping a new vid to YouTube now. This one's gonna shut em' down :wheel:

.

Be careful tightening the mirror bolts on those Chinese windscreens, they are realllllly brittle

Sent from my XT1254 using Tapatalk

Nifty7Fifty

- Due to the keen interest from the real men on this forum, I've decided to continue supporting this post with performance updates, and by answering questions from those of you who are actively performing this swap.

- This is the last thing I'm going to say to the "gurus" . . . I understand all of the geometric hieroglyphics that you throw out there. Honestly, I really do, I'm one of those "weird" people who actually enjoys math. However, there is a point where common sense trumps all that crap. The ZX14r rear shock was engineered for the fastest production bike in the world (Kaw H2 notwithstanding). The ZZR1400 is alot heavier (590lbs.) and vastly more powerful (twice the HP & torque) than an RC36. All of it's components are engineered to withstand the forces generated by all of that raw power, and you keyboard mechanics actually think the shock is not good enough for your 1990's 750 class sport bike?? RFLMBO :laughing6-hehe: :laughing6-hehe: :laughing6-hehe:

That's a good one, ok I'm done now.... wait.. here's another... Why don't you give Kawasaki's engineering dept a call, Tell them you think the rear shock on their crown jewel rocket ship is "too soft" for your 25 y/o sport-cruiser :tour:

Alright, back to business... I've put some more miles on the Ninja Viffer this week, took a couple notes, and shot a video with my camera mounted to the bike demonstrating suspension movement under various conditions; Hard accelerating, braking, fast riding and cornering on very bumpy, dippy roads. Will upload soon, be on the lookout . . .

.

For someone who has joined 2 months ago you have a very high opinion of yourself and low esteem for those that make VFRD for what it is.

Good thing is that one can choose which posts to read, ignore or block (it works both ways, I know)

Dutchy

Nifty7Fifty

- Due to the keen interest from the real men on this forum, I've decided to continue supporting this post with performance updates, and by answering questions from those of you who are actively performing this swap.

For someone who has joined 2 months ago you have a very high opinion of yourself and low esteem for those that make VFRD for what it is.

Good thing is that one can choose which posts to read, ignore or block (it works both ways, I know)

Nice to meet you too. :beer: Sorry you feel that way. Do you have anything interesting to add to the post, or just stop in to talk shit?

.... A very welcoming and friendly bunch, aren't you?

Nifty7Fifty

Dutchy

Nifty7Fifty

- Due to the keen interest from the real men on this forum, I've decided to continue supporting this post with performance updates, and by answering questions from those of you who are actively performing this swap.

For someone who has joined 2 months ago you have a very high opinion of yourself and low esteem for those that make VFRD for what it is.

Good thing is that one can choose which posts to read, ignore or block (it works both ways, I know)

Nice to meet you too. :beer: Sorry you feel that way. Do you have anything interesting to add to the post, or just stop in to talk shit?

.... A very welcoming and friendly bunch, aren't you?

Like I posted earlier I can wait until you buy a 6th gen. You will have my undivided attention .

Dude great video ! And the rear shock works perfect !

Nifty7Fifty

Dutchy

Nifty7Fifty

- Due to the keen interest from the real men on this forum, I've decided to continue supporting this post with performance updates, and by answering questions from those of you who are actively performing this swap.

For someone who has joined 2 months ago you have a very high opinion of yourself and low esteem for those that make VFRD for what it is.

Good thing is that one can choose which posts to read, ignore or block (it works both ways, I know)

Nice to meet you too. :beer: Sorry you feel that way. Do you have anything interesting to add to the post, or just stop in to talk shit?

.... A very welcoming and friendly bunch, aren't you?

Yes and if you can try and be civil we will get on just fine.

Dutchy

Yes and if you can try and be civil we will get on just fine.

How about you get on with yourself. I'm still waiting for your valuable input on this topic... you know, the topic that the thread was created for?. . . Nothing? . . .oh well, guess you did just stop in to show your ass. Well, if we're done measuring dicks now can you please stop trolling this thread, bub? There's honest folks in here sharing real info, Thanks.

Switchblade

Dude great video ! And the rear shock works perfect !

Thanks for the feedback brother !!

.

Nice.

That shock seems to be working great. I can't wait to see other do this mod. Right now I'm leaving mine stock but maybe in the future I'll be doing this mod for sure.

Thanks Bill. That latest video shows good range of motion with no bottoming. Personally, I try to avoid riding in fields! In my old car racing days, when somebody wound up in the grassy infield run-off area we called it agricultural racing :biggrin: . Can't wait to get it in and mounted.

Cheers,

Glenn

What I would like to see is a compare vid whit the orginal shock ridden same roads as the vid posted in post #87 whit the ZX14 shock

keny

What I would like to see is a compare vid whit the orginal shock ridden same roads as the vid posted in post #87 whit the ZX14 shock

I don't know how beneficial that would be, Keny. The original shock is 25 years old. His 25 year old shock may not be in the same condition as yours or yours the same as mine.

I am happier than I ever thought I would be with this outcome - way better overall than I expected. I can't wait to try it myself. I don't expect it to compete with, or equal, a new Ohlins or other aftermarket shock, but remember, it only costs 10% of that option. I couldn't say no to that.

We are starting to run out of both OEM and aftermarket support for these bikes due to their age and that will continue. I don't know if you can still buy water pumps for these, for example. You cannot for the original V45/V65's and a couple of folks on another forum figured out how to machine parts to make a water pump rebuild kit and even start providing us with rebuilt water pumps to buy. Others have built replacement spark boxes that are better than the originals. This is how we will keep them on the road for the future - with forums like these and innovative thinking. I have adapted newer technology to a couple of my old bikes over the years - technological advances that didn't exist when the bikes were built - that have proven to be better than the original pieces when they were new. We keep on learning with things like this.

Cheers,

Glenn

Dutchy

Nifty7Fifty

- Due to the keen interest from the real men on this forum, I've decided to continue supporting this post with performance updates, and by answering questions from those of you who are actively performing this swap.

- This is the last thing I'm going to say to the "gurus" . . . I understand all of the geometric hieroglyphics that you throw out there. Honestly, I really do, I'm one of those "weird" people who actually enjoys math. However, there is a point where common sense trumps all that crap. The ZX14r rear shock was engineered for the fastest production bike in the world (Kaw H2 notwithstanding). The ZZR1400 is alot heavier (590lbs.) and vastly more powerful (twice the HP & torque) than an RC36. All of it's components are engineered to withstand the forces generated by all of that raw power, and you keyboard mechanics actually think the shock is not good enough for your 1990's 750 class sport bike?? RFLMBO :laughing6-hehe: :laughing6-hehe: :laughing6-hehe:

That's a good one, ok I'm done now.... wait.. here's another... Why don't you give Kawasaki's engineering dept a call, Tell them you think the rear shock on their crown jewel rocket ship is "too soft" for your 25 y/o sport-cruiser :tour:

Alright, back to business... I've put some more miles on the Ninja Viffer this week, took a couple notes, and shot a video with my camera mounted to the bike demonstrating suspension movement under various conditions; Hard accelerating, braking, fast riding and cornering on very bumpy, dippy roads. Will upload soon, be on the lookout . . .

.

For someone who has joined 2 months ago you have a very high opinion of yourself and low esteem for those that make VFRD for what it is.

Good thing is that one can choose which posts to read, ignore or block (it works both ways, I know)

TBF Dutchy (and all the respect in the World as I consider you a very cool guy), Nifty has come in for nothing but opposition from people who've experienced absolutely nothing of Nifty's hard work. If I were an admin, I'd simply clean this thread up and remove all the useless junk posted by armchair experts and have it as it is...a good guide on a mod that people can choose to have a go at or leave well alone. VFR forums, in my humble opinion, are amongst the snootiest I use, I avoid all of them except this one (which I still visit infrequently) simply because of the attitude that seems to float around VFR owners. Present company excluded obviously :)

I don't know how beneficial that would be, Keny. The original shock is 25 years old. His 25 year old shock may not be in the same condition as yours or yours the same as mine.

It would give a reference on how mutch wheel travel the stock shock use compare to the ZX14R.

Still I think the fact that the VFR has a 16kg/mm spring (or spring rate, how mutch force in kgs the spring needs to compress one mm), and the ZX14R has a 9,8kg/mm spring is not a thing that can be ignored. And if you translate that to lbs and inch, its 35,3/0,039 for the stock spring and 21,6/0,039 for the ZX14R spring.

That means that whit the same force on the spring, the ZX14R spring compress a lot more So if a force of 50kgs is pushed on the spring, stock spring (and shock) compress 3,125mm and the ZX14R spring (as shock) 5,1mm, or 1.97mm more! and the wheel moves more than the shock, becorse of the linkage rato! I don´t know what the stock VFR linkage rato is, have not mesured it. And in this case the linkage is moded, so the amount the rear moves compare to same shock movement is not the same.

And I seriusly would like to know how mutch a difference the likage change has done to the amount a wheel travel compare to shock movement! So still questions that are whitout a anwser

I´m not saying that the ZX14R shock is bad quality, suspension tech has sure progress in 25 years.

I Think big effort is put in to try this setup.

And I have a high technical shool degree, and do a lot of work on bikes also,

keny

I don't know how beneficial that would be, Keny. The original shock is 25 years old. His 25 year old shock may not be in the same condition as yours or yours the same as mine.

It would give a reference on how mutch wheel travel the stock shock use compare to the ZX14R.

Still I think the fact that the VFR has a 16kg/mm spring (or spring rate, how mutch force in kgs the spring needs to compress one mm), and the ZX14R has a 9,8kg/mm spring is not a thing that can be ignored. And if you translate that to lbs and inch, its 35,3/0,039 for the stock spring and 21,6/0,039 for the ZX14R spring.

That means that whit the same force on the spring, the ZX14R spring compress a lot more So if a force of 50kgs is pushed on the spring, stock spring (and shock) compress 3,125mm and the ZX14R spring (as shock) 5,1mm, or 1.97mm more! and the wheel moves more than the shock, becorse of the linkage rato! I don´t know what the stock VFR linkage rato is, have not mesured it. And in this case the linkage is moded, so the amount the rear moves compare to same shock movement is not the same.

And I seriusly would like to know how mutch a difference the likage change has done to the amount a wheel travel compare to shock movement! So still questions that are whitout a anwser

I´m not saying that the ZX14R shock is bad quality, suspension tech has sure progress in 25 years.

I Think big effort is put in to try this setup.

And I have a high technical shool degree, and do a lot of work on bikes also,

I understand what you are saying. BUT, the numbers may not represent the reality for a few reasons. We have to consider the materials, valve/orifice design, fluid and gas used. Yes, linkage and stroke as well.

What matters to me is how it feels and handles. I'll let you all know once I've done the swap. Maybe if it works to my satisfaction as well as Bill's and maybe a few other folks who also do the swap, then maybe a few non-believers might realize it could be a good thing. We will see.

Cheers,

Glenn

keny

I don't know how beneficial that would be, Keny. The original shock is 25 years old. His 25 year old shock may not be in the same condition as yours or yours the same as mine.

It would give a reference on how mutch wheel travel the stock shock use compare to the ZX14R.

Still I think the fact that the VFR has a 16kg/mm spring (or spring rate, how mutch force in kgs the spring needs to compress one mm), and the ZX14R has a 9,8kg/mm spring is not a thing that can be ignored. And if you translate that to lbs and inch, its 35,3/0,039 for the stock spring and 21,6/0,039 for the ZX14R spring.

That means that whit the same force on the spring, the ZX14R spring compress a lot more So if a force of 50kgs is pushed on the spring,

Like nifty said, 200bhp on tap verdus our weasley 90ish bhp is a good give away on what the shock can handle.

Forget figures, you're no expert on them so why reference them? Just hold your opinion until you either give it a go or others do and report the same benefits over the old (and shit from new) original shock. A plank of wood would be an improvement over 20+ years old stock shocks for most at this stage

NAIL . IN . THE . COFFIN

What's to debate?

So the bike is back together with the hybrid ZX/VFR shock.

The softness issue is gone altogether - the  rear end moves up and down like it used to - but now with the benefit of proper damping!

[video: https://youtube.com/embed/PBDBjLt6t_o?html5=1&fs=1]

The one thing I do notice is that the seat height is slightly lower that with the original shock. This might actually be of benefit to some riders who would prefer a lower seat height. However, it also makes the bike stand-up more when on the side stand - bringing it quite close to vertical. It wouldn't take much of a push (wind) to make it tip over on the other side. 

I don't know if the dog-bone hole adjustment would address the height / side-stand issue (?)

Other than that - it seems to work well.

So the bike is back together with the hybrid ZX/VFR shock.

...

The one thing I do notice is that the seat height is slightly lower that with the original shock. ...

I don't know if the dog-bone hole adjustment would address the height / side-stand issue (?)

...

Dude... how tall are you?

.... or how low is your bike?

Looks like you have 6" between you and the seat when straddling the bike...

Your   ruff  on  the  ol'girl  but  the  rear  shock  looks  like  it  is  working  great .

All credit to you Nifty - thanks for conceiving of this mod and for taking the time to document the process so that the rest of us can take advantage of this low-cost option. 

I'm certainly going to need to modify the dog bone and raise the rear end. Will likely be in-touch to get some advice on where best to position the new hole; from your video it doesn't look like it needs to move very far. Although, I'm going to hold-off until I hear what other options you're exploring...

In the meantime - it looks like riding weather has returned to Toronto! 

Possible alternative to modding the dogbone. . .  swap in a 1986 - 87' VFR700/750 dogbone. 

They are nearly identical, except for the length.  The 86' is actually a better build quality.  The 1987's on up look like the RC36-1 pictured.  The style change was for weight saving only, the dimensions are the same for 86' to 87'.

[image: 20151228_214035.jpg]

[image: 20151228_214901.jpg]

[image: 20151228_215220.jpg]

[image: 20151228_214136.jpg]

[image: 20151228_215658.jpg]

[image: 20151228_220801.jpg]

[image: 20151228_221205.jpg]

[image: 20151228_222500.jpg]

Another great discovery!

Nifty - how does the 22mm difference in hole position compare with the modification you made to your original link?

Is it likely to end-up Higher / lower / same? 

Cheers.

Higher  me  think   ..

Any news regarding this project? I'm really on the edge of repairing the stock or make the best solution replacement from an other bike.

Thanks for the update!

Hmm, the way I see it there should be clearance when the bike is on the ground. Why don't you jack up the swingarm a bit to see? Curious how much load is needed.

Cheers,

Glenn

I have used the older style link and there is just enough room at ride height for the shock to work without any clearance issues.  I am a bit larger than most (around 235 lbs.) and when I'm on the bike the shock compresses and rebounds fine.  The raised height is also a big upgrade from the stock shock along with the improved damping and performance.  Thanks for the thread, guys!

KOCONUT, 6/6/2016 at 4:02 PM

I have used the older style link and there is just enough room at ride height for the shock to work without any clearance issues.  I am a bit larger than most (around 235 lbs.) and when I'm on the bike the shock compresses and rebounds fine.  The raised height is also a big upgrade from the stock shock along with the improved damping and performance.  Thanks for the thread, guys!

Thanks for posting this !!  I haven't had time to test my 87' link but I knew it would be real close.  Are you running the Zx-14 spring or did you swap on the original VFR spring?  Also, when you're running it hard and the shock is going through it's full range of travel, could you feel any contact on any big rebounds?

Thanks bro!

Nifty

I haven't ridden very much with the new shock yet.  I've got all the fairings off for repaint right now.  Kept the original spring in there.  If I find it still is a little too soft for me I'll probably pull the shock and swap springs

Few update pics. Last one is gap with me sat on it...

[image: image.jpeg]

[image: image.jpeg]

[image: image.jpeg]

[image: image.jpeg]

[image: image.jpeg]

Man that is a slick looking exhaust! :)

Cheers 😀

Yea it was on the bike when i bought it, luckily.

MIG, a French exhaust company, went t-u many years ago.  Shame, they are lovely.

Ciao,

7 hours ago, JZH

MIG, a French exhaust company, went t-u many years ago.  Shame, they are lovely.

Ciao,

Had one some time ago, oval with dual outlets and a carbon weave that I've never seen before.  Still running an ebay alert for it but nothing ever comes up.

Just another quick pic while i rolled it outside for a minute. This is the shorter older rear linkage and front forks pulled through quite a long way. It leans over a lot on the stand but seems stable. Note the pegs and heat shields are still off but you can get an idea of clearance from this...

[image: image.jpeg]

. . . Just checking in

After 2000 miles on the ZX14R spring, I took her apart last month and swapped in the original 1990 VFR red spring onto the ZX14R shock to see the difference.  Got 500 miles on the new setup so I thought I might chime in with some data points..

~ I'm currently 215 pounds butt naked, probably around 230 with the gear I typically ride with.

~ The Zx14r spring is plush and uses the full range of the shock.  It will give you more of a cruiser/touring feel.  Actually, at my age now, I really like the way it handled.  It felt like Cadillac built my bike, couldn't feel a thing but it still took turns well, accelerated sharp and braked fine.  Very pleasant ride.

~ 2 cons with the ZX spring: 1) It would give me a slow bounce on the bigger dips in the road, just one single slow bounce, more like a counter-balance type deal. and 2) you wouldn't want to race it like that.  It took turns good at a semi-spirited pace, but I wouldn't want to push it real hard with the "cadillac" suspension.  Now that could just be me, there was nothing to make me feel that it wouldn't handle fast turns at high speed, but my test piloting balls only grow so big.

~ Both of those cons should be minimized by lighter weight riders. 

~ The original "red" 1990 VFR spring on the ZX shock definitely puts it back to the sports side of things.  MUCH firmer plus strong feedback from the road.  Still stays connected to the road far better than my original 1990 shock ever did.  You can feel a HUGE improvement in rebound and damping vs. the original VFR shock.  Still more comfortable than a full-on modern sport bike though, as I tested a newer Ninja and Gixxer on the same day with the VFR, and the VFR still feels like a "sports-tourer" compared to them. 

~ I will continue to run the VFR spring and take more notes.  So far, I am very pleased with the results regardless of what spring to use.  I currently favor the VFR spring on the Zx14r shock, most likely due to my size.  Although I loved the comfortable ride with the ZX spring, I feel more confident in the twisties with the stiffer spring.

~ I originally lowered my front end 1 inch, but after installing the red spring I felt the need to raise it back up a half inch.  So to be clear, my forks are pulled through a half inch now, or if you prefer, the front end is a half inch lower than factory.

Nifty

[image: 20160624_193810.jpg]

Great feedback, Nifty! Thanks. I'm like you and then some - well north of 215 lbs in gear. We're getting ready for a cross country move, so no more wrenching on the bikes until next winter. Then it gets the ZX-14 shock, '86 dogbone and original spring. That will raise the rear a bit so I'm leaving the forks where they are. The new place is about an hour and a half away from the race track I did a lot of laps on in the past - Atlantic Motorsport Park. Maybe the VFR and I will get a few laps in there one day.

Cheers,

Glenn

2 additional notes I forgot to mention in the previous post:

- the factory 3rd gen spring is a little longer than the Zx spring, so you won't need to tighten the preload nearly as much to achieve the correct sag...  I'm not home now but I believe I'm only around 15% down on the threads. 

- I was interested to see if there was any wear on the shock eyes or on the shock mounts on the bike, or anywhere on the frame, due to the modifications made to the shock.  In particular, I was curious how the hardened metals held up after filing.  I did anticipate seeing some minor "friction marks" here and there, especially on the shock eyes.  But I'm happy to inform you that to my surprise, after 2000 miles everything looked EXACTLY like the day I installed it.  There was not a single groove, scratch, wear mark or anything.  The integrity of all the modified parts was flawless.  Absolutely no contact on the frame or swingarm as well.

Nifty

To agree with what Nifty said and offer a little more data, I've ridden mine a couple of times now (electrical gremlins getting in the way) and I'm currently 180lbs. I've found the back to be vastly improved, so much so that my forks now let the team down a bit. I'm on an 87 dogbone and forks are through about 40mm+

As an aside, my reg rec is too hot to touch after running the bike for a few mins, is that normal on these? I've since relocated the starter solenoid behind the battery and opened up some air flow around this area, I'll dig the pics out if anyone is interested.

Anyway, final stance pics with all parts refitted...

[image: image.png]

[image: image.png]

Time to upgrade the RR to a Shindengen SH847 or FH020 from www.roadstercycle.com

The oem RR's do normally get very hot and that is why they do not seem to last as long as modern mosfet and brand new series regulator/rectifiers.

Just checkin in. . . Awesome riding weather here in the NorthEast lately.  I'm really diggin the way it handles with the red spring now.  I'm set about halfway on the "comp", a tad tighter on the rebound.  Rides beautiful, great handling, perfect blend of stiffness and damping! 

Cheers!

Nifty

10 hours ago, Nifty7Fifty

Just checkin in. . . Awesome riding weather here in the NorthEast lately.  I'm really diggin the way it handles with the red spring now.  I'm set about halfway on the "comp", a tad tighter on the rebound.  Rides beautiful, great handling, perfect blend of stiffness and damping! 

Cheers!

Nifty

Great feedback, Nifty! Thanks. I'm like you and then some - well north of 215 lbs in gear. We're getting ready for a cross country move, so no more wrenching on the bikes until next winter. Then it gets the ZX-14 shock, '86 dogbone and original spring. That will raise the rear a bit so I'm leaving the forks where they are. The new place is about an hour and a half away from the race track I did a lot of laps on in the past - Atlantic Motorsport Park. Maybe the VFR and I will get a few laps in there one day.

Cheers,

Glenn

Good morning Nifty,

Thanks for the update. With the work you've put into the research and testing, this has now become a proven bolt-on mod right down to the base settings (at least for bigger guys like us). We have arrived in the Northeast. Our leaves are just starting to change colour now. It will be spectacular. The garage isn't quite finished and we're only half unpacked, so no bike work until mid- to late-winter. But, look out in the spring! 

Cheers,

Glenn

slovcan, 9/22/2016 at 7:41 AM

Good morning Nifty,

Thanks for the update. With the work you've put into the research and testing, this has now become a proven bolt-on mod right down to the base settings (at least for bigger guys like us). We have arrived in the Northeast. Our leaves are just starting to change colour now. It will be spectacular. The garage isn't quite finished and we're only half unpacked, so no bike work until mid- to late-winter. But, look out in the spring! 

Cheers,

Glenn

Hey Glenn just checking in here...  Congrats on the move and hope you're settled in good now!  Can't wait to hear your report after doing the mod.  Still all good, in fact, everyone who takes it for a spin comments on how nice she rides!  I took my buddy's 2014 Ninja 650 out for 3 hours last Friday, and I couldn't wait to get back on my VFR.  I feel so confident with the rear suspension at this point, that I wouldn't swap it out for anything else, regardless of price or whatever.   Like Y282 mentioned though, you start to really notice the weakness of the stock front end... I serviced my forks to factory specs awhile back, just to freshen them up.  They're ok for now, I'll probably do a front end swap at some point in the future. 

Ride safe bro !!

Nifty

Nifty7Fifty, 10/19/2016 at 0:01 AM

Hey Glenn just checking in here...  Congrats on the move and hope you're settled in good now!  Can't wait to hear your report after doing the mod.  Still all good, in fact, everyone who takes it for a spin comments on how nice she rides!  I took my buddy's 2014 Ninja 650 out for 3 hours last Friday, and I couldn't wait to get back on my VFR.  I feel so confident with the rear suspension at this point, that I wouldn't swap it out for anything else, regardless of price or whatever.   Like Y282 mentioned though, you start to really notice the weakness of the stock front end... I serviced my forks to factory specs awhile back, just to freshen them up.  They're ok for now, I'll probably do a front end swap at some point in the future. 

Ride safe bro !!

Nifty

Hey, thanks Nifty. It's going to take a while longer to get settled in! We've been doing a lot of work here - first up was a new garage and then some interior work for the missus. I did find time for a few short rides, though, on both the VFR and the Trophy. Have to start watching out for the leaves now, as beautiful as they are to look at!

I do know what you mean about the front end. I feel it now, and expect it to be accentuated with the new rear shock. I think we really need a fork brace on these things, too. I'll deal with that later.

Cheers,

Glenn