im new to this site but have had my cbr f2 for 2 years. i wanted to know what size rear tire theese bike came with. i put a 180 on mine but i seen a lot of em have 160's on em i was wondering what you have.

 

Avon Viper Sport AV60...160-60...

You can usually go up one size. I'll probably go to a 170-60...same model when these wear out...

They are sticky tires...though I had to break loose the rear yesterday pretty good to get into heavy traffic.

 

Even a basic search on here would reveal that this has been discussed to absolute death...

but here's my $.02 anyway...

Your rim is designed to run a 160. You suspension geometery is for a 160. A 170 is marginally unsafe, and a 180 wraps so much that is is REALLY unsafe and makes the bike ill handling.

Others will disagree with me, but my opinion comes from 16 years of sportbike riding experience and 10 years of running a motorcycle shop...

 

160/60 is the optimum shape for the 4.5" rim of the F2.

I put a 170/60 on my F2 wheel for the track bike last night....just cause it was all I had. It rolls the outside edge over kind of alot....I'd hazzard a guess its no wider than a 160 is when installed. I bet a 180 looks weird....it might handle a little...umm....funny.

I have some viper supersports for my zx6r ready to go on after I wear my supercorsa's out....I bought them on the free front tire deal last year....anxious to try them.

 

i noticed that it was talked abought after posted ... my bad. i got the bike with a 180 on it. so last summer i put a 180 on again not knowing what the stock size was. i havent had any problems riding wise have had it over 140mph and the dunlop i bought always grabs great rides straight with no wobble. only problem i had was it rubbed part of my brake line off didnt puncture i cought it before it went that deep, but with a little adjustment on the line its fine.

 

You are mostly correct...but one size up...depending on the tire brand and model and design I think is ok. In fact, sometimes better.

The thing with going with a bigger tire, even on a rim designed for it...is that the steering effort will be higher.

Those choppers you see on shows like Orange County Choppers...with the big wide tire..are damn near impossible to turn a corner...a u-turn is a skill in itself on those car tires they put on a chopper...

 

Your 4.5" tire will fit a 160 (max). Anything bigger will change the tire profile from its intended design and make the bike handle like crap.

That's not quite right. It depends on the wheel. for example, as previously mentioned, the F2 has a 4.5" wheel. You can't put anything bigger on there and have it fit properly. The F3 comes with a 160 stock. But it has a 5" wheel and can fit a 170 properly.

 

No, really 1 size up isnt ok. The tire is designed to bead on a particular rim. Any deviation means the tire has to deform from its best configuration to bead up. A 170 is not that different, true (depending on the manufacturer anyway) but its still being bunched up and having its profile altered from the way it was designed. Yes it will go on, yes it will bead up and probably not leak, but give me the same bike and a same rider on a track, and I bet you money the bike goes better with the right width rim. As for doing a 170 for looks, a 170 doesnt really look that much wider, and stuff a 180 on that rim will probably get you laughed at by guys who know what they are doing.

 

how would a 180 look weird? all the new bikes come wit em and they are smaller bikes. the 180 might not be the stock tire and might not be the right tire from what i seen on some of theese posts butit looks better than the stock pizza cutter that comes on theese bikes and from driving my bros 88 600wit a 160 and my friends 89 1000 with a 160 it my bike grabs better. on flat and comming out of turns.

 

180 baby!!! i think it looks A TON better!!!

i know it looks like its crooked but thats the tail,i didnt have it screwed down!

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