VF500 F2 Rear Wheel Impossible!

A few additional thoughts:

Slowbird's Pirelli Sport Demon Options (staying with the 150/70-17R)

• 100/90-16F and 150/70-17R, a 56mm difference (642mm - 586mm = 56mm)
• 110/90-16F and 150/70-17R, a 38mm difference (642mm - 604mm = 38mm)

Stock VF500F (shock L=346mm)

• 100/90-16F and 110/90-18R, a 69mm difference (655mm - 586mm = 69mm)

Calculations on my 17" wheel conversion using CBR600F rims and a DMr F4i shock (L=352mm):

• 110/70-17F and 140/80-17R, a 70mm difference (655.8mm - 585.8mm = 70mm), R=27.0d, T=100mm (Close to stock, R27.0d, T104mm - This is the set-up I have selected, using Avon Roadriders.)
• 110/80-17F and 140/80-17R, a 48mm difference (655.8mm - 607.8mm = 48mm), R=27.5d, T=122mm (The trail number is getting pretty far out there with a 110/80-17 up front.)

Given these numbers (and not knowing the CBR600F2 shock length - which I don't think will be any longer than the F4i that I have) I would think the 100/90-16 might be a better option, to help get back in line the bike's stock geometry.

My concern with the 110/90-16F that you are considering is the same as I had on my conversion - that the bike is starting to level out (not enough difference front to back) and that rake and esp. the trail numbers are getting too far out there.

Caveat: I am not a frame designer. As Jamie D has written it may be best to go with the selection you think is best and then to see how the bike handles - it could be that the 110/90-16F will work fine, though my thinking is that the numbers look off.

Hope this is of some help!

 

Ok, let me clear this up. My recommended tire sizes for the VF500F with CBRF2 wheels:

Front: 120/60-17
Rear: 150/70-17

Gearing is 16/44 for the 84-85 model and 16/43 for the 86's. (Daugherty Motorsports - Motorcycle Suspension Performance and Modification)

If you are going to race the bike 100% of the time I'd say you should go ahead and look at the rake, trail, etc. Otherwise - don't bother. The F2 wheels with radial tires will be such an improvement over stock that you really won't need to try and hit some magical set of numbers (which you never would be able to anyway). Adding a little to the rear shock length is nice but not an absolute must. We are talking about improvements, and the F2 wheels by themselves make a big one.

 

Can't comment on the F2's but the CBR600F rims are about 10% lighter, when compared to stock.

 

Absoltely, the F2 wheels are not heavier than stock. Anyone who has ever ridden a VF500F before and after the conversion will rave about the results. Only those who people who have not will question it.

 

Thank you for the post.

As noted, I was probably being a bit overly academic on the numbers - still, I would still suggest a 100/90-16F over a 110/90-16F for Slowbirds's project - to get closer to the stock geometry.

On a side note for F2 wheel conversion owners - based on my model, your tire picks are on the money - not that I doubted this ;-)

• F4i shock (L=352mm) 120/60F and 150/70R = 27d rake, 102mm trail
• stock shock (L=346mm), 120/60F and 150/70R = 28d rake, 108mm trail

 

100/90-16 it is then.

No F2 front wheel for me....I've dumped enough $$ and time into this bike.

 

Ok....so the new sprockets are on their way. 16/41....Jamie recommends 16/43 but I assume that's to stock gearing and I'd like to rev lower on the hwy.

I'm also hoping with the less teeth in the rear the rear tire will have a tad bit more clearance by moving farther back.

Also (for some odd reason) the local parts place could only get me a 110 link chain. He said all I have to do is cut it down to 108.

Should I cut it down to 108?

 

Yes, you have to measure the chain and decide how many links to cut off. It's not necessarily going to be 108 especially considering that you are going with a smaller rear. That's why you have to lay it out and see.

 

Well I may leave it 108 since I would like the wheel a bit further back from the swingarm.

 

FYI: 108 Link chain with a 16t Front and 41t rear is almost too long....almost.


Jamie, are the Torque specs for the Rear axle nut different with the F2 mod?

The wheel spins fairly freely until I torque the rear axle nut to 70 ft lbs and then it becomes harder to spin.

How should it spin when moving it by hand (with proper chain slack) and the nut torqued down?

 

The torque is the same. Do you have the center spacer installed inside the wheel between the bearings? When people have a tight condition when torquing the axle down most of the time it's because they forgot to put this tube back in when replacing the bearings.

 

I haven't touched the bearings or anything in the Wheel. That tube is there though it is loose in there.

 

So how freely should the rear wheel spin with everything attached and torqued down?

 

I would think this should match the stock 'spin'. It sounds like, from your description, that you are concerned that something is binding?

 

"Binding" doesn't seem like the correct term to describe how it is.

I think "tight" would be better.

If I spin the wheel by hand it will maybe do a full rotation before stopping.

 

Okay "tight" helps in the description. Is the chain is adjusted correctly - a proper slack of 15-25mm?

 

Are you using the F2 center spacer tube? You do not want to use the VF500 part because this part is only there to maintain proper spacing of the bearings so it must match the wheel it's in. If you are running the F2 part and it's loose in there I'd say maybe your bearings aren't seated far enough. That would certainly cause the wheel to feel tight.

 

Yes.....infact it may even be on the loose side. Chain and Sprockets are new if that matters. Just installed them.

I am using whatever was inside the wheel when I bought it off of the previous owner. When installing the wheel sometimes the tube doesn't line up with the hole, so you turn the wheel and it falls into place.

Nothing has changed with the bearings since I posted pictures of the wheel earlier on in this thread. If the bearings weren't seated wouldn't it be noticeable?

 

Could it be possible that the bearing spacer was crushed by over torquing the axle nut? Could this cause the inner races to no longer be centered on the bearing - making the wheel hard to turn?

 

^^ Could be.....though I always use a Torque wrench and the wheel does spin free-er when I loosen the axle nut. (IIRC)