I have an 88 CBR 1000f with what appears to be a 17x5 inch rear wheel with a 140-80-17 tire. Since I am new to riding I will ask a couple of dumb questions. First: Can I upsize my rear tire to something like a 150-70-17 which at the moment still seems to be an available sport tire? Second: If not is there another factory wheel or cheap replacement that will bolt right up and allow a larger tire? Third: How large a wheel/tire combo can I go in the factory swing arm?
Now before the clearance discussions begin, I am planning to remove the factory fender, and anything else not specifically needed, and there seems to be about 3/4" to 1" clearance on either side of the tire. That being said I'm not asking if I can wedge a 240 under there, but something in a 180 or 190 would be nice.

 

Welcome to the Forum !
Questions:1 Yes a 150 will fit and run fine 2 No, not without clearance and handling issues to my knowledge 3 180 or 190 would LOOK nice, but your bike'll handle like a pig. Don't waste your energy, and your cash. Removing the fender and anything else not needed will give you one result - wet wiring, and probably a wet a..se, and likely other electrical problems.It won't help with clearances, anyway, to my knowledge.My Buddy Donald tried it all on his 88, and after spending plenty, went back to a narrower tyre.
The early models handled very well with 150's, good traction and cornering - others have tried going bigger, not a good idea.The later models, like my 1990 take a 170 tyre as standard, I run a 180, but if you go for more width you'll find out, as many have before you, that going too wide isn't a good idea.

 

Thanks Shadow, I appreciate the info. I had called several tire places and each time the person wanting to price tires for me had to lean over and ask the person sitting next to them and then came the standard response: That tire was designed especially with that bike in mind or vice a versa, and in short that is the tire you need, and we don't have that in the style you are looking for but thank you anyway.

 

Smaller tyres always give better handling perfromace