Tire sizing

Been doing a little reading on what tire sizing some of the other riders use for their kz400's . I'm in need of a new set of tires, my question is what do you guys think about 120/90-18 for the rear and 100/90-18 for the front?

I was told my stock front 3.00 is equal to about 100/80-18 and figured the extra 10 for the front would be sufficient for a little size increase while still keeping good handling. Will the rear 120/90-18 fit without being too snug? Any suggestions or recommendations? Thanks!

Here's a conversion chart:

www.webbikeworld.com/Motorcycle-tires/tire-data.htm

3.00-18 and 3.50-18 are the original size tires. Of course hard to find inch size tires, but possible if you search. I see a lot of 3.50-18 on ebay, didn't look for the 3.00 but probably some of those too. For sure a 120/90-18 is too big for the rear wheel. A 110/90 would be pushing it, a 100/90 may be a better choice for the rear. Front I think a 90/90-18 would be pretty good. Ideal would be find the 3.50 and 3.00 original size tires.

I have a 110/90-18 for the rear right now and it seems to perform well. I'd just like a tad bigger tire. I guess i should just ask directly, since i just want to know if it can be done, if anyone has installed a 120/90-18 on their Kz?

What is the wheel width? I wouldn't use a 120 unless the wheel is at least 2.15" wide.

RonKZ650 wrote: ... For sure a 120/90-18 is too big for the rear wheel. A 110/90 would be pushing it, a 100/90 may be a better choice for the rear. Front I think a 90/90-18 would be pretty good. Ideal would be find the 3.50 and 3.00 original size tires.

Good Fortune!