If you're going to put big rubber on a wide rim, go for it. if you try to put big rubber on a narrow rim (like the stock rim) it will pinch the tire in a way that effects steering. let me tell you why.

a normal fitting motorcycle tire is oval shaped when installed. when you install large rubber on a skinny rim, the outcome is no longer Oval. Rather, it's quite trapezoid in shape. When you go to turn in, you will be dancing on a knife edge. the tire will drop you to your knee in a quick hurry and force you to turn rather sharply. this is what is commonly referred to as tire dive. It's manageable, to a point. going as extreme as you are about to will put it over the line of manageable into the realm of very crashable.

put the rubber on a properly sized rim. you don't put 10.5" floaters on Neon rims, why would you put a 300mm tire on a 4" rim?

 

What I'd say you should do, instead of wasting money on wider rims/tires, is just get a good set of stock size Pilot Powers for the bike, and ride it like you stole it. I pay more attention to chicken strips than tire size anyways. wider tires on stock rims could potentially be quite dangerous if you're not careful. I've read that wider tires can get very squirmy in turns, not sure because I havent tried.

stick with whats on it. its not like having a 130/70/17 tire on a busa or something. THAT would be inadaquate for sure.

 

i plan on changing the control arm and the rim that is why im asking what is good with the width of the newer bikes, if i change my control arm im not keeping my stock rim im gonna go for something newer, i like the stock 900rr and i think they came on the f3's too the six spoke rims i dont know how to post a pick on here. to my understanding the newer rims are wider and come with the size tire im looking for, keep in mind i say i want a big tire but i think some of you may be visualizing a 300mm tire or something along those lines i want a stock size tire for a f3 wich im pretty sure is right around a 180 its not that much bigger than what i have now but its enough for me to be happy. i know what you guys are talking about putting a tire that is to big for a rim on there that it wont handle right and pretty much wont be safe so thats why i am trying to update the rim as well as the tire. i cant find a way of putting it that you guys will understand. maybe im stupid or something but its just something im gonna do. i would prefer to have the info going into the project instead of figuring it out for myself when its gonna cost me time and money. know what i mean...

 

on a stock f1 rim, you can fit up to a 150 without jeopardising the crown. anything bigger wouldnt work right.