Cbr F4 Shock In Place Of Vfr Shock

What a great day Saturday was! I found time to get two major mods completed and both seem to really help.

1st, I was able to install an F4 shock in place of the VFR's original. This is EXTEMELY EASY as the shocks are only 1/2" different in total length. I did not have to fabricate any brackets. I did have to drill some holes in the battery box to tie rap the reservoir to, add 1/2" of shim/washers to the top tie to get the height correct, but that was all. The exchange took 20 minutes MAX.

One other note is that I did revalve and add a 950 spring to it through aftershock as the original spring was old. total cost was $40 on ebay for the shock plus $300 to aftershock, or $340 total for a 'internals are new' shock with rebound and compression adjustment.

Being that I am 250lbs necked, I really needed a stronger spring and this has fit the bill!! My SAG was 50mm and is now 25mm with more preload left! The bike definitely handles much nicer now and holds the lines in the curve much easier. I was having issues everything feeling loose in turns and I believe it was simply the rear end swaying on the weak (for my wt) spring. All that is gone now.

overall length difference of .5"

[image: f4vsvfrshock.jpg]

where I mounted my reservoir

[image: reservoirmount.jpg]

While I was under there, I threw on a catless header too. I don't notice a lot of volume difference, but I believe I am feeling the front end lift much easier now. I don't have a dyno, so that is my only test at this point. I am still using coyze's map and it seems to be running just fine too. Apparantly, he has developed the super map! I still plan on gutting my exhaust sometime in the near future and once this is complete, I will try Tinymind's map and see if it runs better/worse on my setup.

I also weighed all the parts I have removed and swapped and I am down 20lbs so far on my bike. Not bad!

deadweight

[image: deadweight.jpg]

new and improved!

[image: nowshecanbreath.jpg]

now she can breath!

[image: 5thvs6thgen.jpg]

if anyone else wants to do it i have a good shape cbr F4 shock :D

Cool mods. i like the exhaust work

Hey turtle, Welcome to 2003! :P I'm pretty sure I pioneered both of these mods to the VTEC. IMHO, the headers are a waste if you don't open the rest of the exhaust. I ran the F4i spring towards the max and I was about 170lbs at the time.

BaileyrockCool stuff Dale, but a .500" shorter shock? That's not a good thing unless you want to drop/lower the bike which I doubt you would want to do. :unsure:

You will screw up the handling of the in a major way without compensating for this shorter shock, 5mm is a big change and your talking 12.5mm. If anything you would want a slightly longer shock to improve turn-in, the shorter shock will slow steering a huge amount. You will not like it!

Also that .500 is doubled or tripled in read ride height by the rocker ratio of the rear suspension, I'm guessing it will lower the rear of the bike by 1-1 1/2 ". :unsure:

didnt you do the same and just make a spacer to compensate for the shorter length?

that didnt sound right????? :unsure: smile.gif

767fixerdidnt you do the same and just make a spacer to compensate for the shorter length?

that didnt sound right????? :goofy: smile.gif

I missed where he added 1/2" of washers! :beer: Never mind my post! :goofy:

According to the pic, that's not a 1/2 inch difference. Looks to me about 3-4mm which is still too short but if he's been riding it with WAY too much sag all this time, it will still feel better. Throw a couple of washers on the top of the upper bracket and you'll be good to go.

Edit: see he's all ready done that. Life will be good.

Well, I read the whole post, and I think he's out loving life with his new shock right now!! :thumbsup:

I just hope he doesn't get too happy and bottom that resevoir out on his chainguard... that could be bad... or just a bad angle on the camera? :goofy:

SEBSPEEDWell, I read the whole post, and I think he's out loving life with his new shock right now!! :thumbsup:

I just hope he doesn't get too happy and bottom that resevoir out on his chainguard... that could be bad... or just a bad angle on the camera? :goofy:

It probably won't hit. My res is mounted further forward than that attached to the sub frame and it doesn't seem to hit

thanks to all the input. u have to love this place as people actually read what you post, and think about issues you might have missed and try to help out!

here are the sag numbers I put in a spread sheet 'now' was prior to mod, 'future' is after mod:

what '-5' doesn't really mean anything. it is just a base line number in 'mm' that i was using to see where i was heading I am actually 8mm biased to the rear from what i 'think' is the factory 'ideal'. not great, i know, but the springs have improved the ride so much i dont care!

as you will see, the 'original' condition of the bike with me on it was actually 'close' to what a normal rider sees from the factory regarding front to rear bias.

but with me on it (now) it was basically doing a 18mm wheelie!! with the .95s on front and 950 on rear, things are still a little rearward balanced, but it is much more improved over my (now) ride....

front sag fork height rear sag rear height front to back difference

factory setup 35 43 30 0 -5

original (w/ me) 55 44 50 0 -6

now (pre mod) 15 50 50 15 13

future (post mod) 15 50 25 0 3

(oops, spacing isn't working on the post like it is in the edit section....so i just attached tiny xls file.)

regarding reservoir, i am glad to hear that yours is forward jeremy and yet still no issue. i was definitely concerned about this, but could not figure out where else to put it as the hydraulic line is only so long.....

i know someone might mention that 7mm down on front is issue, but unfortunately, i am not sure what to do about it at this time. i may try cutting my spacers in my forks some to see if i can 'unload' the spring some as my adjustment screw is out about 15mm and i still have minimal sag in front. i don't exactly understand this with my weight, but it is what it is.

my_sag_settings.xls

I am thinking of changing my 99 VFR over to the 929 or F4i shocks. Main advantage is compression damping adjustable? The F4i needs heavier springs and revalving but is closer in height, whereas the 929 is shorter but spring is correct weight. I also have an almost new CBR1100xx shock but that looks like the VFR shock, so not worth changing probably. I had a Works Perf shock on the 100xx when I had and it was great but I don't want to spend the $750 on the VFR.

MikeG

MikeGI am thinking of changing my 99 VFR over to the 929 or F4i shocks. Main advantage is compression damping adjustable? The F4i needs heavier springs and revalving but is closer in height, whereas the 929 is shorter but spring is correct weight. I also have an almost new CBR1100xx shock but that looks like the VFR shock, so not worth changing probably. I had a Works Perf shock on the 100xx when I had and it was great but I don't want to spend the $750 on the VFR.

MikeG

I would go with the 929 shock if I were you. You'll get compression damping and you can easily add spacers to make it the right height. The F4i shock would work too, but then you would have to get a new spring for it.

The CBR-XX shock is also shorter than the 5th gen stock, but it's rated for about 100 lbs more than the VFR spring. So, if you're on the heavy side or do a lot of two-up riding, it might be the way to go. Of course, you can just get a heavier spring for the F4i or 929 shock too. :blink:

Congrats Dale, suspension mods rawk. I recently got a 929 for 5ht gen. Now all I need are new springs & valves for the front and I'll be all set for the Fall meet.

so far I gathered from this is that and F4i shock conversion is easier than a 929 shock conversion, and the benefits are similiar. Right?

On the issue of spring, could we fit the original 5th gen spring into the F4i shock?

snowparangso far I gathered from this is that and F4i shock conversion is easier than a 929 shock conversion, and the benefits are similiar. Right?

On the issue of spring, could we fit the original 5th gen spring into the F4i shock?

This is a Vtec shock option, IMO the 929 shock is the best swap for the 5th gen and has the same spring rate as the VFR.

btw the vfr spring will not work on either the F4i or 929 shock.

also the cbr 1100xx shock runs a stiffer spring( I think a 17 kg) and with bolt into either, but if I'm not mistaken it's like 1/4" shorter than a 5th gen and 1/4" longer than a 6th gen. and only has the same adjustments as the stock VFR shock.

what BR said....

i am 250lb so i knew i had to respring and revalve anyways and on a 6th gen, it is almost a 'drop in' (just add the 1/4"-1/2" stack of washers and mount the remote reservoir)

I have a line on a F4i shock for my 5th Gen (2001 model). Will I be able to add shims to adjust for the length difference?

And if I do go with the recommendation of some of you, for the CBR 929 shock, would I have to shim the top end?

Grateful for inputs, especially from guys that have done this mod.

ThrottlestopI have a line on a F4i shock for my 5th Gen (2001 model). Will I be able to add shims to adjust for the length difference?

And if I do go with the recommendation of some of you, for the CBR 929 shock, would I have to shim the top end?

Grateful for inputs, especially from guys that have done this mod.

http://www.vfrdiscussion.com/forum/index.p...mp;hl=929+shock

do a search on '929 shock' for other posts.

you will have to shim...too much for just a simple stack of washers though.

Thanks, TC.

Are the basics the same for a 3rd gen as well? F4i/929??

Thanks...

Come alive THREAD!! The problem I see using these f3/f4 shocks.... found said problem after I ordered 2 of them ... Is that the preload adjuster is at the bottom where you cant adjust it??? Ill be reselling those and install the 929 one.

SLO97VFR

Come alive THREAD!! The problem I see using these f3/f4 shocks.... found said problem after I ordered 2 of them ... Is that the preload adjuster is at the bottom where you cant adjust it??? Ill be reselling those and install the 929 one.

Is the adjuster hidden by the bottom linkage? Is it something else?

TBH I really don't mind if it's difficult to set; I'd only set it once and be done with anyway...

Also, what is the difference between an F4 shock with red spring and an F4 shock with yellow?

no difference in the shocks...

if you look at the 1st post pictures, you will see the black adjuster. it is difficult to get to. like you said, if you set it and forget it, fine...otherwise, you might want to consider something else. i have tried to set it with spanner, but haven't spent a lot of time on it and didn't have success. once i get the bike out of my garage (no room to manuever) i'll see if i can do it.

I wouldn't recommend using Cozye's map with Catless headers unless you richen the whole map. Cozye's map is much richer than stock, but still probably not rich enough for catless. Tinymind's map is in the download's section.

Ryanme17

I wouldn't recommend using Cozye's map with Catless headers unless you richen the whole map. Cozye's map is much richer than stock, but still probably not rich enough for catless. Tinymind's map is in the download's section.

this is a shock thread and that was a random post.....but since you did it....i have run cozye's map for 2 years now....stinks to high heavens because it is VERY rich....no problem running with catless....oh, and she runs like a scalded dog too....i have not tried Jasons, but meant to....having no issues with cozyes, i just never got around to it.

Better a little rich than lean. Safer that way and less drivability problems.

turtlecreek

this is a shock thread and that was a random post.....but since you did it....i have run cozye's map for 2 years now....stinks to high heavens because it is VERY rich....no problem running with catless....oh, and she runs like a scalded dog too....i have not tried Jasons, but meant to....having no issues with cozyes, i just never got around to it.

It was random in the sense that it did not follow the previous posts, but the original post was about both the shocks and the catless header. I missed it way back when, but it does talk about using Cozye's map and just wanted to throw that out there because running lean can potentially cause damage. Just sayin'

Ryanme17

turtlecreek

this is a shock thread and that was a random post.....but since you did it....i have run cozye's map for 2 years now....stinks to high heavens because it is VERY rich....no problem running with catless....oh, and she runs like a scalded dog too....i have not tried Jasons, but meant to....having no issues with cozyes, i just never got around to it.

It was random in the sense that it did not follow the previous posts, but the original post was about both the shocks and the catless header. I missed it way back when, but it does talk about using Cozye's map and just wanted to throw that out there because running lean can potentially cause damage. Just sayin'

AH...gotcha...so long ago, i didn't remember....you are right about lean....all i can tell you is 2 years and no problems and lots of fuel smell, so i don't "think" it is an issue, but have not dynoed it to know for sure...

turtlecreek

AH...gotcha...so long ago, i didn't remember....you are right about lean....all i can tell you is 2 years and no problems and lots of fuel smell, so i don't "think" it is an issue, but have not dynoed it to know for sure...

Fuel smell is probably as good of an indication as you can get, short of shelling out the bucks for a wide-band 02 sensor. A dyno itself won't tell you lean/rich, unless it's hooked up to a sensor.

I think there is some question on whether the 950 lb spring is the correct rate for TC's weight!

He was able to get desired Rider Sag, but were not sure about it having Any or proper Free sag. We plan on installing a 1200 lb spring on this shock soon and testing results, we'll post Free & Rider sag numbers as soon as we get them. :wheel:

BR

BaileyRock

I think there is some question on whether the 950 lb spring is the correct rate for TC's weight!

He was able to get desired Rider Sag, but were not sure about it having Any or proper Free sag. We plan on installing a 1200 lb spring on this shock soon and testing results, we'll post Free & Rider sag numbers as soon as we get them. :fing02:

BR

BR, how did this work. I'm wanting to use the same F4 shock and 1200 lb spring on my 6th gen... and I'd like to get the parts ordered today from the cheapest source so I can be ready for T-Mac. Any advice?

Michael

[image: f4vsvfrshock.jpg]

turtlecreek

no difference in the shocks...

if you look at the 1st post pictures, you will see the black adjuster. it is difficult to get to. like you said, if you set it and forget it, fine...otherwise, you might want to consider something else. i have tried to set it with spanner, but haven't spent a lot of time on it and didn't have success. once i get the bike out of my garage (no room to manuever) i'll see if i can do it.

Hi guys... does the access to the preload adjuster continue to be an issue?? have you found an easy solution to adjusting on the fly?? I change regularly from hardbags to no hardbags and would prefer to be able to adjust preload with realtive ease...

How did the stiffer 1200 lb spring go??

Any updates??

Bueller??

Up!!

Hi all..I also have the 03 vtec...so how easy is this cbr6 f4 shock change...mine has gone and now way does it need serviced..do I need to jack the linkage up and remove the back cyclinder pipes..all tips welcome as I'm a newbie...

tomoyzf13

Hi all..I also have the 03 vtec...so how easy is this cbr6 f4 shock change...mine has gone and now way does it need serviced..do I need to jack the linkage up and remove the back cyclinder pipes..all tips welcome as I'm a newbie...

Contact member Jamie Daugherty Motorsports

http://www.vfrdiscussion.com/forum/index.php/links/link/1157-daugherty-motorsports/

tomoyzf13Hi all..I also have the 03 vtec...so how easy is this cbr6 f4 shock change...mine has gone and now way does it need serviced..do I need to jack the linkage up and remove the back cyclinder pipes..all tips welcome as I'm a newbie...

there are many write ups in the how to section or suspension forums cover all your questions.

no exhaust removal needed

Sent from my SCH-I405 using Tapatalk 2

thanks guys...ill get onto to it as soon as ive un-seized my chain adjuster hub!!!

Hey guys,

Long time lurker and first time poster. I've just purchased a CBR600F4i shock for my 2003 6th Gen as well as one of these to (hopefully) overcome the issue of preload adjustment.

http://www.biketude.com/wp-content/gallery/vfr-shock-replacement/img_1241.jpg

The picture is shamelessly ripped from the following article:

http://www.biketude.com/do-it-yourself/replacing-shock-on-vfr-800-a/

I've yet to use either as they're still in the post but, at only 65kg (145lb), I'm hoping to get away with running the shock with no adaptation. I'm sure it'll probably need a stiffer spring, but only time will tell.

PardonezMoi

Hey guys,

Long time lurker and first time poster. I've just purchased a CBR600F4i shock for my 2003 6th Gen as well as one of these to (hopefully) overcome the issue of preload adjustment.

http://www.biketude.com/wp-content/gallery/vfr-shock-replacement/img_1241.jpg

The picture is shamelessly ripped from the following article:

http://www.biketude.com/do-it-yourself/replacing-shock-on-vfr-800-a/

I've yet to use either as they're still in the post but, at only 65kg (145lb), I'm hoping to get away with running the shock with no adaptation. I'm sure it'll probably need a stiffer spring, but only time will tell.

The spring is way to soft for the VFR . But a nice DIY and WELCOME ..

I just received this shock in the post from an eBay seller, and it looks rather bent to me. You can see it in the second photo by the angle the lower spring spacer sits at. Any opinions on whether to send it back or try and salvage it? I'm unsure whether shock shafts can be straightened in the same way fork stanchions can.

[image: IMG_2131_zps03114978.jpg]

[image: IMG_2132_zps38ad81b5.jpg]

Return it's crap ..

Always keep your eye out for a used Ohlins or Penske...love my Ohlins BTW...

Best O luck.

Matt

PardonezMoi

I just received this shock in the post from an eBay seller, and it looks rather bent to me. You can see it in the second photo by the angle the lower spring spacer sits at. Any opinions on whether to send it back or try and salvage it? I'm unsure whether shock shafts can be straightened in the same way fork stanchions can.

[image: IMG_2131_zps03114978.jpg]

[image: IMG_2132_zps38ad81b5.jpg]

Either it was damaged in shipping or misrepresented. I'd look into getting a refund if it is the latter.

Hopefully the seller is cooperative. Ebay "buyer protection" is difficult at best and turned out to be useless to me in a similar situation. Best of luck with it.

There is noway in hell that shock bent like that in shipping, at a guess it has been mistreated or off a crashed bike.

The guy refunded me in full with no quibbles. I was really impressed with how he handled it and he let me keep the shock. I've another on order now and a free shock to experiment with.

Your lucky man .

So now I have a spare shock to disassemble and perhaps even reassemble afterwards if I'm doing well, does anybody know how much pressure an F4i shock takes? I'm assuming 150PSI but I've read some Showa units take 225PSI.

No takers?

Just in case you are still interested ... have a look at this: http://www.peterverdone.com/archive/05shock.htm

Roughly 242 PSI in the stock shock off an '05 CBR 600 RR.

RC36Rider

Just in case you are still interested ... have a look at this: http://www.peterverdone.com/archive/05shock.htm

Roughly 242 PSI in the stock shock off an '05 CBR 600 RR.

Dude great article . One of the best explanation of a rear shock .

"Spring and damper, know the difference. Preload is for changes geometry, Spring is for changes in load, and the damper is for changes in velocity. It really is that simple. "

Good to see that someone is interested. :wink:

Yeah! While his website is somewhat lacking in glitz and orderly presentation, it is more than made up for by the numerous nuggets of great info. :fing02:

Just found this also:

Nitrogen Pressure (14.5 psi =1 bar): 285 psi

Source: Race Tech's DVS sheet for my 6th Gen's stock Showa.

I'm planning on doing the F4i shock swap on my '07 VFR. I know I'll need to change the spring, but at 180 lbs doing moderate street riding/commuting in Florida, can I avoid modifying the internal components if the shock came off a bike with low miles? I'm mainly looking for a smoother ride.

What spring do I need?

PS: yes, I know I could ask Jamie, but I'd prefer to firsrt gather a quick general opinion before a professional one.

Okay, just to be clear, I can bolt in a stock 929 shock as an improvement on my 5th gen, and all I might need are some washers/spacers to get this correct? There are lots of 900/929/954 shocks out there. Some with white and some with yellow springs. Are they all the same? I like this idea and the inherent low cost of the upgrade. There are lots of decent looking low mileage shocks for sale for less than $50!

Silverbrick

Okay, just to be clear, I can bolt in a stock 929 shock as an improvement on my 5th gen, and all I might need are some washers/spacers to get this correct? There are lots of 900/929/954 shocks out there. Some with white and some with yellow springs. Are they all the same? I like this idea and the inherent low cost of the upgrade. There are lots of decent looking low mileage shocks for sale for less than $50!

Different gens of the CBR 900 have different shocks. Even the 929 and 954. None really fit the 5th Gen VFR w/o mods.

Look at DMr's offering here: http://www.daughertymotorsports.com/vfr800.html

Pay attention to the extension at the top of the shock.

Underoath87

I'm planning on doing the F4i shock swap on my '07 VFR. I know I'll need to change the spring, but at 180 lbs doing moderate street riding/commuting in Florida, can I avoid modifying the internal components if the shock came off a bike with low miles? I'm mainly looking for a smoother ride.

What spring do I need?

PS: yes, I know I could ask Jamie, but I'd prefer to firsrt gather a quick general opinion before a professional one.

At 180 lbs you would be in the 18-19 kg range if i remember correctly(stock is 15.3 kg). Yes i would try slapping the spring on and installing the shock, then play with the damping adjustments to see if you like the results. Even if you have to max out one or both adjustments it doesn't matter if you like it. Ideal, no, but I'm sure it would be an improvement over stock. I think the F4i shock is around 3/8" shorter then the vtec so you have to make up that amount by shimming under the top mount, may require a longer bolt.

Check here

http://www.vfrdiscussion.com/forum/index.php/topic/19712-vtec-shock-options/

BR

Silverbrick

Okay, just to be clear, I can bolt in a stock 929 shock as an improvement on my 5th gen, and all I might need are some washers/spacers to get this correct? There are lots of 900/929/954 shocks out there. Some with white and some with yellow springs. Are they all the same? I like this idea and the inherent low cost of the upgrade. There are lots of decent looking low mileage shocks for sale for less than $50!

The 929 Only has the same spring rate as the VFR(15.3 kg), no difference in the yellow and the white springs that were on the Erion version of 929. You will have to make up length of the shorter 929 shock by shimming the top mount bracket which may require a longer top frame bolt.

BR

Baileyrock

Underoath87

I'm planning on doing the F4i shock swap on my '07 VFR. I know I'll need to change the spring, but at 180 lbs doing moderate street riding/commuting in Florida, can I avoid modifying the internal components if the shock came off a bike with low miles? I'm mainly looking for a smoother ride.

What spring do I need?

PS: yes, I know I could ask Jamie, but I'd prefer to firsrt gather a quick general opinion before a professional one.

At 180 lbs you would be in the 18-19 kg range if i remember correctly(stock is 15.3 kg). Yes i would try slapping the spring on and installing the shock, then play with the damping adjustments to see if you like the results. Even if you have to max out one or both adjustments it doesn't matter if you like it. Ideal, no, but I'm sure it would be an improvement over stock. I think the F4i shock is around 3/8" shorter then the vtec so you have to make up that amount by shimming under the top mount, may require a longer bolt.

Check here

http://www.vfrdiscussion.com/forum/index.php/topic/19712-vtec-shock-options/

Thank you!

Do you have any idea of where I should look for compatible springs? Are there any OEM springs that would fit the bill?

Underoath87

[...]

Thank you!

Do you have any idea of where I should look for compatible springs? Are there any OEM springs that would fit the bill?

The OEM F4i spring is tapered. Exact dimensions and rates of OEM springs are not generally published by manufacturers.

This makes finding a suitable OEM spring difficult.

Have a look at Race Tech's website here: http://racetech.com/ProductSearch/2/Honda/CBR600F4i/2002

Scroll down to 'Rear Shock Springs & Kits'. You'll see that they offer 2 models of shock spring:

• SRSP 6016 is suitably tapered
• SESP 60225 is cylindrical and needs adapter collars

IMO, the Daugherty Motorsport offering is a great value proposition given that you get a shock that was fully cleaned, refurbished, re-valved, re-sprung and adapted to the correct length.

Underoath87

Baileyrock

Underoath87

I'm planning on doing the F4i shock swap on my '07 VFR. I know I'll need to change the spring, but at 180 lbs doing moderate street riding/commuting in Florida, can I avoid modifying the internal components if the shock came off a bike with low miles? I'm mainly looking for a smoother ride.

What spring do I need?

PS: yes, I know I could ask Jamie, but I'd prefer to firsrt gather a quick general opinion before a professional one.

At 180 lbs you would be in the 18-19 kg range if i remember correctly(stock is 15.3 kg). Yes i would try slapping the spring on and installing the shock, then play with the damping adjustments to see if you like the results. Even if you have to max out one or both adjustments it doesn't matter if you like it. Ideal, no, but I'm sure it would be an improvement over stock. I think the F4i shock is around 3/8" shorter then the vtec so you have to make up that amount by shimming under the top mount, may require a longer bolt.

Check here

http://www.vfrdiscussion.com/forum/index.php/topic/19712-vtec-shock-options/

Thank you!

Do you have any idea of where I should look for compatible springs? Are there any OEM springs that would fit the bill?

The F4i used a rate of about 14 kg vs a stock VFR rate of 15.3 kg which is soft unless your less then 150 lbs.

I found no other Honda spring is stiffer then the VFR except the XX Blackbird at 16.9 kg.

Sonic springs offer a good selection on springs.

Br

Underoath87   Did you ever get this swap completed?  :unsure:

can i buy a cbr600f4 shock, then add a different spring i see the vfr spring wont fit on it, but will another oem, like a spring from a cbr929 or cbr1100xx. or do i have to buy a after market spring from ohlins or penski etc?

Aftermarket springs aren't especially expensive, but whilst an aftermarket one would fit, the shock valving and the length and stroke probably wouldn't be suitable for a VFR.  

Ciao,