EnduringGuerila's 1990 VFR750FL Build Thread

I'm new to the VFR as I just bought this 1990 VFR750F over the weekend for $700 and drove it home (which was quite scary given the condition of the tires and how it didn't want to lean).

The trooper currently has 55k miles on the odo.

The seller had owned the bike since 2003 and it was his first bike. I believe he was only the second owner of it and left it completely stock other than the rear fender.

Ultimately, I plan on building this into something much sleeker and lighter weight than stock. Something sort of cafe racer / tracker style. I don't care to keep the bike looking original but am quite fascinated with the history of the VFR series. I have read hours of articles, forum posts and watched countless videos on the bike already. Seems I got quite lucky finding a 3rd gen and getting a seemingly great deal.

I have already ordered some parts:

Sheet of all parts/costs

$188 - Tires: Shinko 705 120/70r17 radial and 170/60r17 radial

$220 - new brake rotors, pads (and might need a caliper rebuild kit)

$  57 - complete front fork rebuild kit (bushings, seals, etc.)

$  17 - Maxima 5WT Fork Oil

$    9 - Mahle oil filter

$  21 - Honda GN4 10w-40 engine oil

Not sure if I want to do a front fork conversion or not. I figured I'd rebuild the stock ones and try them some more before deciding but what are most peoples thoughts here?

Don't know yet if I have the Cali version but if I have EVAP and PAIR then I plan on deleting them. This thread didn't really help but at least I know it's possible.

This V4Dreams seems helpful even though he hasn't specifically had a 3rd gen 750.

If you're interested in any of my other projects (unfortunately few are documented):

2005 Subaru OBXT build

Here are the only two pics from the ad before I bought the bike.

The seller said the right side panel "Flew off going down the highway" and didn't go back to recover it.

[image: WhatsApp Image 2020-11-08 at 22.50.22.jpeg][image: WhatsApp Image 2020-11-08 at 22.50.22(1).jpeg]

I took some 'glamor' shots of the bike as I bought it.

[image: 20201113_190401.thumb.jpg.5e2a68415eb852587726473fe3b47442.jpg][image: 20201113_190408.thumb.jpg.db75c75d726a3896e6a5b1fdd7a75db0.jpg][image: 20201113_190413.thumb.jpg.b925869da983c4cb21ff9f0ca5f9d8ea.jpg][image: 20201113_190421.thumb.jpg.cabcd358915b7ac68428f368f6964867.jpg][image: 20201113_190429.thumb.jpg.6d1e344fe9418ca6378fef7221662dbf.jpg][image: 20201113_190434.thumb.jpg.1cec22a3af26f641096f871de48cdd85.jpg][image: 20201113_190443.thumb.jpg.c35c27c6750dd3d57769a0bfe4559a9b.jpg][image: 20201113_190454.thumb.jpg.8485c379a5ccdbf1fce875d475946733.jpg]

Here are pictures of a random bike I found online. I'll likely copy some style ideas from this guys build. (not the fake wood though)

[image: WhatsApp Image 2020-11-08 at 22.50.52.jpeg][image: WhatsApp Image 2020-11-08 at 22.51.05.jpeg][image: WhatsApp Image 2020-11-08 at 22.51.11.jpeg]

reserved

Anyone have a specific recommendation for what jet kit to use? I'm up in Colorado Springs and the bike currently starts without choking and it does feel like the ratio is off.

First of all, congrats.

Most "jet kits" are going to increase the jet sizes, not what you think you need.  First of all go thru the carbs, document what the jets are, confirm the carbs are clean and properly clean them if needed.  Verify the enrichment circuits are working properly.  At least bench-synch them, re-install and test bike.  I doubt you will need any kind of "jet kit".

Any $700 motorcycle I am instantly suspicious of the state the carbs are in.

Yep, bike's jetted to be too-rich from factory for safety anyway. Typically in 10-11:1 AFR range, leaving about 10% HP on table for safety. Adding more petrol will just lose even more power. You need to gather quantifyable data using wide-band O2-sensor and get actual plot of AFR. Most likely at altitude, you'll need to reduce jet-sizes 2-3 sizes from stock.

Reports of people "upgrading" to larger jets and things improving just shows carbs are clogged and needs thorough cleaning. This requires scrubbing entire flow-path of fuel from tank all way to carb venturi. Along with hours of ultrasonic soaking and flossing with matching-size copper wires. Then micro soda-blasting all passages to clear remaining dried petrol. Modern "carb-cleaner" sprays no longer work due to removal of chlorinated compounds. Requires A LOT of elbow-grease to restore carbs back to factory-fresh clean.

The only thing I changed when I rebuilt the carbs on my 1989 RC24 was change the pilot jets from #38 to #40 ... the float needles were replaced at the same time though, check the float height out before and after, the original float needles all read less than spec and the mileage was 51k miles so similar condition .... reduced float height will richen the mixture 

Joe @ V4dreams has a full carb overhaul walkthrough on his site and the O rings for sale 

Ah, so slight correction, I was not intending to imply I needed larger jets when I said I wanted a jet kit. Just that I wanted new jets that were appropriately sized for the VFR and for this altitude.

I have read that don't need to be rejetted here unless you're riding a lot up in the mountains but if the bike is rich from the factory then it'll only be exaggerated here.

So, the stock slow jet seems to be the #40 and the main jet the #130

I then looked up the VFR750R and it has a slow jet of #38 too.

Also wondering if I might need a slightly smaller main jet.

What is the difference between the "VFR750F A" and the "VFR750F AC"?
Is the AC the Cali model?

That is most definitely not the stock front fender. Not sure what it came off of, but it does look like everything else is right.

If you don't keep that center stand there will be a bidding war for it.

AC is Cali.

5 minutes ago, jefferson

If you don't keep that center stand there will be a bidding war for it.

Haha, I actually was planning on removing it for the weight savings. Hadn't decided if I want to sell all the old parts or keep them for... whatever reason. Leaning towards selling, especially if prices are right

Man, for the utility it provides, and the miniscule percent of weight it is, I'd retain it. My 97 would have been a pain in the butt to maintain all these years without it.

1 hour ago, EnduringGuerila

Ah, so slight correction, I was not intending to imply I needed larger jets when I said I wanted a jet kit. Just that I wanted new jets that were appropriately sized for the VFR and for this altitude.

I have read that don't need to be rejetted here unless you're riding a lot up in the mountains but if the bike is rich from the factory then it'll only be exaggerated here.

So, the stock slow jet seems to be the #40 and the main jet the #130

I then looked up the VFR750R and it has a slow jet of #38 too.

Also wondering if I might need a slightly smaller main jet.

Yes, most likely want to go down one size slow and main to start. Just off-idle and partial-throttle is mostly slow-jet and would be where you're getting most stumbling from being too rich (too lean tends to be just lazy revving, but doesn't stumble unless it's really lean).  Mains would be less likely to contribute to your current issues,  but it'll benefit from downsizing as well.

"Jet kits" tend to be designed for common upgrades: full-exhaust system (slip-on mufflers don't change much), pod-filters, cams, etc. The needle tapers are typically modified for less low-end/midrange and more high-end flow. They are really hit-n-miss unless you have exact mods their designers used. Back then, I would spend less time dialing bike in by using dyno-chart with AFR then cutting my own needles on lathe.

Since no kits includes smaller jet-sizes you'll need, best just to get couple smaller sizes from https://www.jetsrus.com/

But first, make sure your carbs are factory-fresh clean with complete refurb using ultrasonic and soda-blasting. Then fine-tune with jetting after making sure your bike is back to factory-specs.

Wow, this is really good conversion, really impressive! Wishing you best of luck with yours. :)

[image: WhatsApp Image 2020-11-08 at 22.50.52.jpeg]

that random bike (above) is an abortion, and i wouldn't copy anything. it was built to impress ppl who know style but nothing about motorcycles. A vfr isn't a good offroad bike so no offroad tires; it's insane !  too much power and weight for dirt, tires no good for street. another show bike.

[image: 281444123_sept132020001.thumb.JPG.7a5269326b303e1f63a30d61483bf699.JPG]

Gas tank has a nice fake "wood" job on it though. Total abortion, I think you should punch that bastard in the bread basket for doing something so heinous to an innocent VFR!

It's just my own opinion and I could be FOS, but I suspect that many 3rd gens were broken for their 8 spoke,  so it pains me to see another morphed in to something else that probably only the person doing it will like. Once they lose interest in it, it will then be broken for parts since it won't have appeal to anyone else.   The gen 3 is such a beautiful and classic design that I wish more were preserved in their original state. I can't remember the last time I saw one in person.  I'd love to own an original example,  but for me time,  money and space make that impractical.   :sad:

Seems like many 3rd gens get crashed and made in to off road rides. Probably cheaper than putting it back to stock. He is not the first, nor will he be the last as parts are getting harder and harder to find...

And then there is this guy....

Or you could do it to a $20,000 bike instead....

It's hard to kill a 3rd gen, but people have tried....they seem to be the one people tear into the most because they can be found so cheap....

I just puked in my mouth a little bit...

burns

I did the same when I saw this one....

5 hours ago, RC1237V

[image: xZ0wQ99.jpg]

Lol, now that's just funny...

13 hours ago, Cogswell

... so it pains me to see another morphed in to something else that probably only the person doing it will like. Once they lose interest in it, it will then be broken for parts since it won't have appeal to anyone else.   The gen 3 is such a beautiful and classic design that I wish more were preserved in their original state. I can't remember the last time I saw one in person.

This is the most conceited shit I have heard in a long time. You're basically saying your uninspired vision for the bike is for them to all stay stock forever. Doesn't matter who owns it nor how they want to use the bike, how they like it to look, how they want to dump excessive money into modding it to become their dream machine. I chose this platform as a huge personal project instead of just flipping it. As mentioned previously, I did extensive research into the bike once I realized it had a uniqueness to it. Yes I was only initially interested because it was a cheap find. It is quite far from a good condition museum piece and more in the 'forgotten 30 year old metal' category. I'll post some more close ups of the bike so maybe that'll put some you at ease for me 'ruining a perfect 30 year old design.' I do agree that, for it's age, the style isn't too bad. But this is not what I would consider the most attractive stock bike.

We'll see how you feel about a machine after you put your blood, sweat, tears and cash into a project. Tell me you wouldn't have a special place for it over something you bought and just maintained. Go build something. And if nothing else, I'm doing the community a favor by offering parts to those that want to keep their bikes stock.

As for the off road comments, you're right, this isn't an off road bike. If you actually look up the tires I already ordered, you'll see that they are mainly a street tire. 90/10 street/dirt. It's still rated for 130 mph which is faster than any of us should be going unless we're tracking the bike which is already stupid because the bike is so heavy. I chose the Shinko 705 instead of the 805, but here in Colorado, I don't want to avoid these sweet mountain roads/trails so I need a tire that isn't a slick. Even the 805s have some insane street performance. I have them on my KLR650 and love them. Cheap and phenomenal grip on and off road, only downside is that they wear out fast... but they're cheap. Buying the 705s was a sacrifice I debated for a while. I spent like 5 hours actively researching tires and their performance in different environments.

[image: PANIGALE OFFROAD1.jpg]

I love the sleek exhaust and how it shows off the rear wheel. I don't know exactly how I'll design it but I've seem some interesting creations, like this custom box:
https://youtu.be/acFyVCPJMBk?t=69

Just to piss more people off, here's a very short story.
I'm an IT System Administrator, aka computer nerd, by day. Well, I received two free Macs that ran slow as hell. This is because Apple sabatages their machines by pushing updates to their machines that can't run it well and their OS is quite heavy. These Macs were slow as hell, so I violated their purity, added SSDs, 2TB 2.5" drives and put Linux on them. Boom, now they run faster than ever (because Linux > MacOS) and the Macs are usable again. You might say "just don't update the Mac" but Apple shit gets outdated FAST and won't allow you to install the latest web browsers or other apps very quickly, effectively forcing people to buy their newest hardware which is ridiculously overpriced for the hardware they put in them.

jefferson, 11/13/2020 at 7:29 AM

That is most definitely not the stock front fender. Not sure what it came off of, but it does look like everything else is right.

I thought ST1100 - which fits 3/4 Gen forks, I have one somewhere. But not quite the same.

[image: ST1100.jpg]

Build what you want mate, there's heaps of stock low mileage VFRs still out there for the purists (one even belongs to me!)

Just don't trash the (increasingly rare and valuable!) parts you don't want, That would be a waste.  

As the pics upthread clearly show, the 3rd gen frame has a big, ugly feature that is very hard to deal with when using anything other than the OEM rear cowling.  That's why you really wouldn't want to start from a 3rd gen if you were planning a tidy custom bike--but maybe that's why they're cheaper than 4th gens!

Good luck with it.

Ciao,

JZH

I just added some 'glamor' shots to post two with the other pics.

You can see it isn't perfect but it also wasn't trashed or anything.

The seller said the tank pad started to come off and when removing it, took the original paint with it...

That's why I posted those pics, it's your bike, and your money, you should enjoy it the way you see fit. (Although that one made from license plates is an abortion) No one complained when Apex Andy, or Sebspeed made streetfighters out of their bikes. This guy riding the red VFR off road doesn't look like he has any regrets either...

OP. welcome to the forums.  Looking forward to what you end up doing to your bike.  

It is your bike, do what you will with it.  Some people will always have their opinions but I can appreciate the efforts that you are and will be going through to make this project yours.

I get that there are purists that want to just leave their bikes bone stock.  More power to them.  Then there are those that like to tinker, to fabricate, to do what they want to THEIR own bike.  Go for it and good luck!

any custom where you're sitting on a short plain plank seat is an ugly failure.

JZH, 11/15/2020 at 4:34 AM

As the pics upthread clearly show, the 3rd gen frame has a big, ugly feature that is very hard to deal with when using anything other than the OEM rear cowling.  That's why you really wouldn't want to start from a 3rd gen if you were planning a tidy custom bike--but maybe that's why they're cheaper than 4th gens!

How insensitive! My fat butt 3rd gen looks just fine from certain angle, in a certain light. Was that design a structural thing? I think I've seen some modified tails on them. Presumably welding is involved. Can a 4th gen tail be swapped in?

The tail fairings are nearly the same (rounded on the later bikes, flat on the earlier ones); I was referring to the sides of the frame to which the rear subframe attaches.  The 4th gen has no big, sculpted castings (much more like the RC30/RC45 in that respect).

Ciao,

JZH

Build is on a slight hold. Really want to get my lift table ordered, the tires keep getting delayed from being shipped and I want to build a dyno. With all the other projects I have, I really need to knock some other stuff out first.