im not sure what the stock tire numbers are off the top of my head. You can probably find that in the "tech vault" on this forum. (or look at the tires on your bike of course)
The rear that I bought was a 170/80-15 and I went a little fatter on the front tire so I forget those numbers. Theres a lot of threads on here about front tire sizes so Im sure you'll be able to find the info. If you do go a little bigger in the front you'll have to modify the front fender bracket to accommodate the size.
