What do I need to do to run a 120/70/17 on this CBR F3? I am assuming I need to drop the bike in the triples to compensate for the larger diameter tire. My calculations are that I would need to drop it a total of 5mm. I figure that if the tire is 10mm larger in diameter, then it would make the bike sit 5mm higher. Could somebody verify this for me.

Thanks,
Josh

 

Why do you want to do that?

 

I was thinking that the taller the profile would give me more contact while cornering. It also seems like it would have better turn in. I also think I read somewhere that the some of the F2/F3 racers preferred running that combination.

 

I have that right now love t

 

Any changes to the front end?

 

If you are not racing, or on the track, you will never notice the difference. I run 120/70's now because that is the popular size and I buy take offs for the track and I never noticed a big difference. The bike will be a little harder to turn in because of the greater rake angle.

If you do go to the track then I would think to raise the forks a little, but I am not sure by how much. One would think 5mm by what you said but I am not sure when it comes to the angle of the forks.. I am not a geometry wiz.

 

Throw the tire on and ride it for a while. I noticed mine turned on a lot easier.
Make adjustments after you break-in the tire and see how it feels.
Or better yet talk to a racer/mechanic who does track setups.

 

Well, I would like to eventually race in WERA. So, I am looking to get the best setup right out of the gate. I already ordered a 120/70/17 for the front and I wanted to make sure it wouldn't be unstable if I just slapped it on there without any changes to suspension.

Thanks for all the feedback,
Josh

 

My guy installed my 70 on my bike with the stock'ish settings.
No adjustments yet as I need to re-spring mine for my heavy weight!
It'll flick a lot faster so be aware.. but surely nothing "unsafe" I'd say.
Keep us updated.

 

http://forums.13x.com/forumdisplay.php?f=12

Go to that link. If you plan on racing, there are a lot of guys at the wera forums who know a lot of stuff about racing and how to get setup.