86vfr700 and f4i forks. good bedfellows?

Ok im trying to figure out if what i wanna do is going to work.

Bike is an 86 vfr 700 and id like to use a set of f4i forks ive got on this bike. Are they going to be long enough with a 17" wheel front and back with no raise to the rear suspension? Maybe it will make the bike sit level?

They're a little shorter but they'll work, the bigger issue is the steering stem difference. You'll need to press the VFR stem into the CBR lower. Or, you can buy my 900RR front end that was supposed to be used on my VFR700... it's already converted/painted/steering stops are done/new All Balls tapered bearings installed too. The forks have Racetech springs and are in good shape, no leaks. PM me if interested, lets make a deal, I want them gone!

[image: View Post]SEBSPEED, on 23 June 2010 - 12:36 PM, said:

They're a little shorter but they'll work, the bigger issue is the steering stem difference. You'll need to press the VFR stem into the CBR lower. Or, you can buy my 900RR front end that was supposed to be used on my VFR700... it's already converted/painted/steering stops are done/new All Balls tapered bearings installed too. The forks have Racetech springs and are in good shape, no leaks. PM me if interested, lets make a deal, I want them gone!


Ive already got the f4i forks and triples, or else that would be a good idea. Im way more interested in that exhaust uve got :)
Any idea if the stem is the same size?

[image: View Post]flyguyeddy, on 23 June 2010 - 12:52 PM, said:

[image: View Post]SEBSPEED, on 23 June 2010 - 12:36 PM, said:

They're a little shorter but they'll work, the bigger issue is the steering stem difference. You'll need to press the VFR stem into the CBR lower. Or, you can buy my 900RR front end that was supposed to be used on my VFR700... it's already converted/painted/steering stops are done/new All Balls tapered bearings installed too. The forks have Racetech springs and are in good shape, no leaks. PM me if interested, lets make a deal, I want them gone!


Ive already got the f4i forks and triples, or else that would be a good idea. Im way more interested in that exhaust uve got :)
Any idea if the stem is the same size?


Stem is the same size(same bearing kit part#), just the length is different(VFR is longer).

Exhaust is here for the taking... as are the freshly gold painted wheels... and the CDI box, wiring harness, coils, etc, etc, etc...

[image: View Post]SEBSPEED, on 23 June 2010 - 01:18 PM, said:

[image: View Post]flyguyeddy, on 23 June 2010 - 12:52 PM, said:

[image: View Post]SEBSPEED, on 23 June 2010 - 12:36 PM, said:

They're a little shorter but they'll work, the bigger issue is the steering stem difference. You'll need to press the VFR stem into the CBR lower. Or, you can buy my 900RR front end that was supposed to be used on my VFR700... it's already converted/painted/steering stops are done/new All Balls tapered bearings installed too. The forks have Racetech springs and are in good shape, no leaks. PM me if interested, lets make a deal, I want them gone!


Ive already got the f4i forks and triples, or else that would be a good idea. Im way more interested in that exhaust uve got :)
Any idea if the stem is the same size?


Stem is the same size(same bearing kit part#), just the length is different(VFR is longer).

Exhaust is here for the taking... as are the freshly gold painted wheels... and the CDI box, wiring harness, coils, etc, etc, etc...


What do u want for it?

[image: View Post]flyguyeddy, on 23 June 2010 - 12:14 PM, said:

Bike is an 86 vfr 700 and id like to use a set of f4i forks ive got on this bike. Are they going to be long enough with a 17" wheel front and back with no raise to the rear suspension? Maybe it will make the bike sit level?
The 86 VFR has 835mm forks. The F4/F4i has 750 mm forks.
Your front end will be about 85mm lower. With any different front end, make sure the front tire does not touch the cylinder head at full bump or you will lock the front and crash.
A buddy put on a 929 front on his 86 VFR and did just that. He milled a custom 1" offset top triple to resolve this issue.

[image: View Post]Franko!, on 13 July 2010 - 11:00 PM, said:

[image: View Post]flyguyeddy, on 23 June 2010 - 12:14 PM, said:

Bike is an 86 vfr 700 and id like to use a set of f4i forks ive got on this bike. Are they going to be long enough with a 17" wheel front and back with no raise to the rear suspension? Maybe it will make the bike sit level?
The 86 VFR has 835mm forks. The F4/F4i has 750 mm forks.
Your front end will be about 85mm lower. With any different front end, make sure the front tire does not touch the cylinder head at full bump or you will lock the front and crash.
A buddy put on a 929 front on his 86 VFR and did just that. He milled a custom 1" offset top triple to resolve this issue.


Franko, when you say offset, do you really mean offset? As in, he moved the forks forward in regard to the steering stem by 1"?

Or, do you mean that he added a 1" drop to the upper triple clamp? If this is the case, then my next question is if he was already using a drop-style triple from the 929/954, or if he had a flat clamp(like RC51 maybe?)?

Flyguy, you really ought to jack the rear end up to retain your geometry(rake/trail).

[image: View Post]SEBSPEED, on 14 July 2010 - 05:23 AM, said:

Franko, when you say offset, do you really mean offset? As in, he moved the forks forward in regard to the steering stem by 1"?
Or, do you mean that he added a 1" drop to the upper triple clamp? If this is the case, then my next question is if he was already using a drop-style triple from the 929/954, or if he had a flat clamp(like RC51 maybe?)?
The upper triple clamp was offset in such a way to make the front forks 1" lower like this -> _/````\_ (don't you love ascii art!!)

[image: View Post]Franko!, on 14 July 2010 - 03:27 PM, said:

[image: View Post]SEBSPEED, on 14 July 2010 - 05:23 AM, said:

Franko, when you say offset, do you really mean offset? As in, he moved the forks forward in regard to the steering stem by 1"?
Or, do you mean that he added a 1" drop to the upper triple clamp? If this is the case, then my next question is if he was already using a drop-style triple from the 929/954, or if he had a flat clamp(like RC51 maybe?)?
The upper triple clamp was offset in such a way to make the front forks 1" lower like this -> _/````\_ (don't you love ascii art!!)


Ok, so it had 1" of drop added.

Now, the other part of my question... what clamp was he using last, just before installing this custom one?

[image: View Post]SEBSPEED, on 14 July 2010 - 07:05 PM, said:

Now, the other part of my question... what clamp was he using last, just before installing this custom one?
He used the factory 929 upper triple. Under hard braking hit front tire hit the valve cover and locked up.
So he made the custom upper triple clamp to effectively make forks ~1" longer.

[image: View Post]Franko!, on 14 July 2010 - 07:10 PM, said:

[image: View Post]SEBSPEED, on 14 July 2010 - 07:05 PM, said:

Now, the other part of my question... what clamp was he using last, just before installing this custom one?
He used the factory 929 upper triple. Under hard braking hit front tire hit the valve cover and locked up.
So he made the custom upper triple clamp to effectively make forks ~1" longer.


Aha, thanks!

Wait a sec, is he also a member here? Does he have black CBR929 or 954 track fairings on his bike?

[image: View Post]SEBSPEED, on 14 July 2010 - 07:13 PM, said:

[image: View Post]Franko!, on 14 July 2010 - 07:10 PM, said:

[image: View Post]SEBSPEED, on 14 July 2010 - 07:05 PM, said:

Now, the other part of my question... what clamp was he using last, just before installing this custom one?
He used the factory 929 upper triple. Under hard braking hit front tire hit the valve cover and locked up.
So he made the custom upper triple clamp to effectively make forks ~1" longer.


Aha, thanks!

Wait a sec, is he also a member here? Does he have black CBR929 or 954 track fairings on his bike?

I have no idea, and can't remember what fairings he put on the bike.
However, he did put on a 6" rear rim.

[image: View Post]SEBSPEED, on 23 June 2010 - 01:18 PM, said:

Stem is the same size(same bearing kit part#), just the length is different(VFR is longer).

Exhaust is here for the taking... as are the freshly gold painted wheels... and the CDI box, wiring harness, coils, etc, etc, etc...



Good place to start PM'ing here son! :cool:

[image: View Post]Franko!, on 13 July 2010 - 11:00 PM, said:

The 86 VFR has 835mm forks. The F4/F4i has 750 mm forks.

just out of curiosity, what's the stock length of '98 CBR600F3 forks?

i have a set which i plan on using, but they were removed from a racebike and were rebuilt by Traxxion Dynamics just before i bought them, so i'm not 100% sure how modified they might be. guy said they were set-up with "all the goodies" (not sure what that entails) for a 190lb rider on an F3, and i'm 165lb normally (still recovering) with the heavier '86 VFR750F... if any of that will matter. :huh:

[image: View Post]KrazieIvan, on 15 July 2010 - 04:57 PM, said:

[image: View Post]Franko!, on 13 July 2010 - 11:00 PM, said:

The 86 VFR has 835mm forks. The F4/F4i has 750 mm forks.

just out of curiosity, what's the stock length of '98 CBR600F3 forks?

i have a set which i plan on using, but they were removed from a racebike and were rebuilt by Traxxion Dynamics just before i bought them, so i'm not 100% sure how modified they might be. guy said they were set-up with "all the goodies" (not sure what that entails) for a 190lb rider on an F3, and i'm 165lb normally (still recovering) with the heavier '86 VFR750F... if any of that will matter. :huh:
The CBR F2/F3 forks are 780mm long (measured from top of upper fork tube to center of axle)

[image: View Post]SEBSPEED, on 14 July 2010 - 05:23 AM, said:

[image: View Post]Franko!, on 13 July 2010 - 11:00 PM, said:

[image: View Post]flyguyeddy, on 23 June 2010 - 12:14 PM, said:

Bike is an 86 vfr 700 and id like to use a set of f4i forks ive got on this bike. Are they going to be long enough with a 17" wheel front and back with no raise to the rear suspension? Maybe it will make the bike sit level?
The 86 VFR has 835mm forks. The F4/F4i has 750 mm forks.
Your front end will be about 85mm lower. With any different front end, make sure the front tire does not touch the cylinder head at full bump or you will lock the front and crash.
A buddy put on a 929 front on his 86 VFR and did just that. He milled a custom 1" offset top triple to resolve this issue.


Franko, when you say offset, do you really mean offset? As in, he moved the forks forward in regard to the steering stem by 1"?

Or, do you mean that he added a 1" drop to the upper triple clamp? If this is the case, then my next question is if he was already using a drop-style triple from the 929/954, or if he had a flat clamp(like RC51 maybe?)?

Flyguy, you really ought to jack the rear end up to retain your geometry(rake/trail).


Why would i want to raise the rear end if im lowering the front soo much with the new forks? Wouldnt that cause extreme angles? This bike will be rode by my ex, so i dont exactly want it too twitchy. (We're still friends,if anyone is thinking foul play lol)

[image: View Post]flyguyeddy, on 16 July 2010 - 07:34 AM, said:

[image: View Post]SEBSPEED, on 14 July 2010 - 05:23 AM, said:

[image: View Post]Franko!, on 13 July 2010 - 11:00 PM, said:

[image: View Post]flyguyeddy, on 23 June 2010 - 12:14 PM, said:

Bike is an 86 vfr 700 and id like to use a set of f4i forks ive got on this bike. Are they going to be long enough with a 17" wheel front and back with no raise to the rear suspension? Maybe it will make the bike sit level?
The 86 VFR has 835mm forks. The F4/F4i has 750 mm forks.
Your front end will be about 85mm lower. With any different front end, make sure the front tire does not touch the cylinder head at full bump or you will lock the front and crash.
A buddy put on a 929 front on his 86 VFR and did just that. He milled a custom 1" offset top triple to resolve this issue.


Franko, when you say offset, do you really mean offset? As in, he moved the forks forward in regard to the steering stem by 1"?

Or, do you mean that he added a 1" drop to the upper triple clamp? If this is the case, then my next question is if he was already using a drop-style triple from the 929/954, or if he had a flat clamp(like RC51 maybe?)?

Flyguy, you really ought to jack the rear end up to retain your geometry(rake/trail).


Why would i want to raise the rear end if im lowering the front soo much with the new forks? Wouldnt that cause extreme angles? This bike will be rode by my ex, so i dont exactly want it too twitchy. (We're still friends,if anyone is thinking foul play lol)



Depending on the front triple clamps and their geometry, you will most likely have to raise the rear and drop the front the get back to stock steering feel. I you dont, when ridden back to back with a standad VFR, the F4i forks will make the "upgraded" bike feel like a chopper.

[image: View Post]cornercarver, on 16 July 2010 - 08:36 AM, said:

[image: View Post]flyguyeddy, on 16 July 2010 - 07:34 AM, said:

[image: View Post]SEBSPEED, on 14 July 2010 - 05:23 AM, said:

[image: View Post]Franko!, on 13 July 2010 - 11:00 PM, said:

[image: View Post]flyguyeddy, on 23 June 2010 - 12:14 PM, said:

Bike is an 86 vfr 700 and id like to use a set of f4i forks ive got on this bike. Are they going to be long enough with a 17" wheel front and back with no raise to the rear suspension? Maybe it will make the bike sit level?
The 86 VFR has 835mm forks. The F4/F4i has 750 mm forks.
Your front end will be about 85mm lower. With any different front end, make sure the front tire does not touch the cylinder head at full bump or you will lock the front and crash.
A buddy put on a 929 front on his 86 VFR and did just that. He milled a custom 1" offset top triple to resolve this issue.


Franko, when you say offset, do you really mean offset? As in, he moved the forks forward in regard to the steering stem by 1"?

Or, do you mean that he added a 1" drop to the upper triple clamp? If this is the case, then my next question is if he was already using a drop-style triple from the 929/954, or if he had a flat clamp(like RC51 maybe?)?

Flyguy, you really ought to jack the rear end up to retain your geometry(rake/trail).


Why would i want to raise the rear end if im lowering the front soo much with the new forks? Wouldnt that cause extreme angles? This bike will be rode by my ex, so i dont exactly want it too twitchy. (We're still friends,if anyone is thinking foul play lol)



Depending on the front triple clamps and their geometry, you will most likely have to raise the rear and drop the front the get back to stock steering feel. I you dont, when ridden back to back with a standad VFR, the F4i forks will make the "upgraded" bike feel like a chopper.


but putting on the f4i triples will lower the front anyway, right? being as the forks are much shorter.

[image: View Post]flyguyeddy, on 16 July 2010 - 09:00 AM, said:

but putting on the f4i triples will lower the front anyway, right? being as the forks are much shorter.


The F4i triple clamps have more fork offset than the VFR parts, which throws your rake and trail off in the wrong direction.

[image: View Post]SEBSPEED, on 16 July 2010 - 09:02 AM, said:

[image: View Post]flyguyeddy, on 16 July 2010 - 09:00 AM, said:

but putting on the f4i triples will lower the front anyway, right? being as the forks are much shorter.


The F4i triple clamps have more fork offset than the VFR parts, which throws your rake and trail off in the wrong direction.


Id be willing to bet that theyd have less offset than the vfr, unless uve mesured them and im way wrong

Don't bet any more than you are willing to lose on this one Eddy.

Seb is right, the rear is often raised and the front dropped just to get the turn in back close to stock. If you go with the other triple clamps and ride it back to back with a stock VFR you will think the "Upgraded" forks bike handles like a chopper...

[image: View Post]Franko!, on 16 July 2010 - 07:19 AM, said:

[image: View Post]KrazieIvan, on 15 July 2010 - 04:57 PM, said:

[image: View Post]Franko!, on 13 July 2010 - 11:00 PM, said:

The 86 VFR has 835mm forks. The F4/F4i has 750 mm forks.

just out of curiosity, what's the stock length of '98 CBR600F3 forks?

i have a set which i plan on using, but they were removed from a racebike and were rebuilt by Traxxion Dynamics just before i bought them, so i'm not 100% sure how modified they might be. guy said they were set-up with "all the goodies" (not sure what that entails) for a 190lb rider on an F3, and i'm 165lb normally (still recovering) with the heavier '86 VFR750F... if any of that will matter. :huh:
The CBR F2/F3 forks are 780mm long (measured from top of upper fork tube to center of axle)



thx Franko :)

[image: View Post]flyguyeddy, on 16 July 2010 - 09:53 AM, said:

[image: View Post]SEBSPEED, on 16 July 2010 - 09:02 AM, said:

[image: View Post]flyguyeddy, on 16 July 2010 - 09:00 AM, said:

but putting on the f4i triples will lower the front anyway, right? being as the forks are much shorter.


The F4i triple clamps have more fork offset than the VFR parts, which throws your rake and trail off in the wrong direction.


Id be willing to bet that theyd have less offset than the vfr, unless uve mesured them and im way wrong



I agree Eddy, from my memory the VFR700 has more fork offset than the F4. I'm not sure why folks here are trying to get you to raise the rear either. My guess is that you would need to do something to raise the front back up because of the shorter forks. The rear suspension could benefit from being raised if viewed by itself. The short F4 forks would certainly give you some grief. An easy solution would be to install the forks flush with the upper triple clamp and run raised clip-ons under the tiple. That would give you a low clip-on position but allow you to extend the forks down for extra clearance. This is all assuming that the F4 forks are even possible, which I'm not 100% about.

If you have any updates on this topic please let us know!

[image: View Post]JamieDaugherty, on 03 August 2010 - 05:31 AM, said:

[image: View Post]flyguyeddy, on 16 July 2010 - 09:53 AM, said:

[image: View Post]SEBSPEED, on 16 July 2010 - 09:02 AM, said:

[image: View Post]flyguyeddy, on 16 July 2010 - 09:00 AM, said:

but putting on the f4i triples will lower the front anyway, right? being as the forks are much shorter.


The F4i triple clamps have more fork offset than the VFR parts, which throws your rake and trail off in the wrong direction.


Id be willing to bet that theyd have less offset than the vfr, unless uve mesured them and im way wrong



I agree Eddy, from my memory the VFR700 has more fork offset than the F4. I'm not sure why folks here are trying to get you to raise the rear either. My guess is that you would need to do something to raise the front back up because of the shorter forks. The rear suspension could benefit from being raised if viewed by itself. The short F4 forks would certainly give you some grief. An easy solution would be to install the forks flush with the upper triple clamp and run raised clip-ons under the tiple. That would give you a low clip-on position but allow you to extend the forks down for extra clearance. This is all assuming that the F4 forks are even possible, which I'm not 100% about.

If you have any updates on this topic please let us know!


i have not tried this yet, as i have not gotten the bike running. im waiting for billy carr to actually REPLY to an email, and send me my damn carb rebuild kit. im getting a little impatient, its been over a month since i sent payment.

[image: View Post]flyguyeddy, on 05 August 2010 - 06:55 AM, said:

[image: View Post]JamieDaugherty, on 03 August 2010 - 05:31 AM, said:

[image: View Post]flyguyeddy, on 16 July 2010 - 09:53 AM, said:

[image: View Post]SEBSPEED, on 16 July 2010 - 09:02 AM, said:

[image: View Post]flyguyeddy, on 16 July 2010 - 09:00 AM, said:

but putting on the f4i triples will lower the front anyway, right? being as the forks are much shorter.


The F4i triple clamps have more fork offset than the VFR parts, which throws your rake and trail off in the wrong direction.


Id be willing to bet that theyd have less offset than the vfr, unless uve mesured them and im way wrong



I agree Eddy, from my memory the VFR700 has more fork offset than the F4. I'm not sure why folks here are trying to get you to raise the rear either. My guess is that you would need to do something to raise the front back up because of the shorter forks. The rear suspension could benefit from being raised if viewed by itself. The short F4 forks would certainly give you some grief. An easy solution would be to install the forks flush with the upper triple clamp and run raised clip-ons under the tiple. That would give you a low clip-on position but allow you to extend the forks down for extra clearance. This is all assuming that the F4 forks are even possible, which I'm not 100% about.

If you have any updates on this topic please let us know!


i have not tried this yet, as i have not gotten the bike running. im waiting for billy carr to actually REPLY to an email, and send me my damn carb rebuild kit. im getting a little impatient, its been over a month since i sent payment.


If we're talking about just fork rake here, I've found these specs:

CBR F4i has 24.0� -- http://motoprofi.com...0_f4i-2006.html)
'86 VFR 750 F has 27.6� -- http://www.math.uwat...VFR_86_info.txt

Fork offset is different than rake. Rake is the angle the forks are leaning back, offset is the distance from the forks to the steering stem. These two dimensions along with the tire diameter each contribute to the trail value. Trail is typically the most focused-upon aspect of a motorcycle front suspension. The handling characteristics of the bike will often follow the trail value, that's why people like to keep an eye on it.