Uh, The 180 is wider.

 

Piss off with the cheasy quote

 

For best handling, you want the narrowest tire that will hold the power. The wider it is, the harder the bike is to tip in. On the other hand, you wouldn't want a 160 tire on a 1000cc ss bike because it would spin the crap out of it.

 

...

I am looking for why's. I can look up the specs online but am curious as to why would you use a 160 when you could use a 180, or visa versa

 

So it really just depends on the power of the bike?

 

Yes and no. Like bush mentioned, partially it has to do with the design of the bike and its intended use. But also, power plays a factor. Like I said earlier, a narrower tire is easier to turn in, but also easier to spin. Designers will look for a happy medium between a tire that's wide enough to manage the power of the bike and one that's narrow enough that the bike handles well. Tires are heavy and resistant to changing direction because they're spinning.

 

Depends on what the bike is designed for. The reason the FZ6R takes a 160 as opposed to a 180 is because that's what the designers put on it. It could cause problems with the chain or swingarm, cause quirky handling, or make it harder to tip in.

 

Those OCC bikes handle like shit mostly because of geometry and ground clearance, but partially due to 300 rear tires.

 

The 6r does not need a 180 to do what it was designed for. It is a newbie bike that owners will likely not modify to make big hp or take it to the ragged edge. It is also cheaper to manufacture and replace, like the steel swingarm vs aluminum. An fz6 owner is more likely more concerned with performance and is more likely to have riding experience and will exploit the handling prowess more than the typical 6r owner.

 

STOCK tire sizes are set at a certian mm to allow the bike to be as agile as possible AND to accept the amount of HP put down to the road....


hence wider tires for larger hp bikes. Anything after that is just another dick measuring contest....

 

the easy answer is what size wheel is on the bike, which comes back to what others were saying about what the bike was designed for. 180's are meant fora 5.5" wide wheel. 160's are meant for a 4.5" wheel. Yeah, there's some fudge factor there when folks decide to go up or down one size of tire, but then you get into issues of tire deformation as you squeeze or stretch a tire to fit on a rim it wasn't designed for. To some folks, its no big deal, but it would be for me.

 

Well said. Whatever came stock on your bike, you can go plus or minus 10mm but that's it. You don't wanna push it by going more. Going from a 160 to a 180 is too much.

 

I'm going to start using a 180 tire on my F3, because its damn near impossible to find 160 take-offs.

 

Narrow tires corner better. Fat tires get more traction in a straight line. I just watched a 250cc GP race and if you look closely their rear tires are just as skinny as their fronts.

 

ok maybe I'm missing something, but aren't the FZ6 and the FZ6R essentially the same bike with different bodies? All of you keep talking about handling and power differences, but when we're talking about the main difference being body panels that doesn't make much sense.

 

Not every aspect of a bike is functional...

Sometimes marketing plays a role, too. I read that when designing the hypermotard, Ducati engineers only wanted to use a singe disc for the front brake. They went with a dual setup because that's what people want, not because the bike needed it.

 

I think the fz6 is pushing close to 90hp and the 6r is about 65hp. The frames are different, the suspension is different, and the swingarms are different too.

 

the engine's been "retuned for midrange" (castrated from peak HP for slightly more torque/midrange).

less power means it needs less surface area for traction...

as mentioned before, it's all a balance -- designers weigh the potential engine output and address its need for traction against the bikes overall desired agility.