F4I Legs, Vfr Tubes

[93 VFR750 RC36]

All,

I know this is probably repeated somewhere but after reading 25 threads I've run out of enthusiasm.

What is needed to put 43mm VFR fork tubes together with F4i legs. The goal is compression and rebound adjustability but with a longer fork (F4i about 15mm too short for my needs). I need at least 735mm overall length to the base of the cap.

Also, what mods should be carried out to get the best performance out of these forks while they're apart? Low friction seals, Racetech valving, polished rod, and . . . ?

Finally, what is the fully extended length of a VFR800 fork? I've searched all over and can't find a good answer. Are they the same as my 41mm RC36?

To avoid confusion, this setup is for a hybrid bike, hence me not having the parts on hand. I want to know I'm shopping for the right bits.

[JamieDaugherty]

You would reuse only the VFR stanchion tubes. Getting the spring spacer length correct is a bit of a challenge, but I can help you there. That's about it, pretty straightforward.

You also have to use the VFR cartridge tubes if you are putting the forks on a VFR. If not you can use either. Keep in mind the VFR cartridge tubes will net you 109mm of travel and the CBR's will give you 120mm. Subtle difference but it can matter for a custom job like you are doing.

[93 VFR750 RC36]

Jamie,

Thanks, I wondered if you would dip in here. I've sent you an email about my '93 VFR forks. I need some valve packs for them and I think that a set of low friction seals might be a good idea at the same time.

Why do you need the VFR cartridge tubes on a VFR but not another bike? Is this due to clearance between the front wheel and the rad with the longer travel?

What overall length should I get out of F4i legs and VFR stanchion tubes?

[JamieDaugherty]

The setup with the F4 lowers is slightly shorter than the stock VFR forks, but just a couple mm. Yes, you need the VFR's cartridge tubes because clearances are critical (with all bikes, really) and that is the easiest way to ensure everything would be ok on the VFR. Since you stated that you are working on a different bike you might be able to use the CBR cartridge tubes if there is enough room. Having 120mm of travel is preferred over 109mm, but it's not the end of the world.

[93 VFR750 RC36]

I've had a look and I can get away with 120mm. In fact, the original forks that I'm replacing have 120mm of travel so they should match up perfectly.

Time to start shopping I guess.

[JamieDaugherty]

Be careful - you'll want to make sure and have 10-15mm of clearance at all positions. You'll want to maintain that because the forks do flex under braking. More than people think! Don't push the limit too far or it will likely cause you problems in the long run.

[93 VFR750 RC36]

Thanks, I'll keep a close eye on clearances.

How much difference to the low friction seals make to handling and when/where would you notice it the most?