98 GSXR FORKS on F2/F3..USD
 

Okay I have been trying to research this for a while. I have a 94 F2. Swapping 98 USD GSXR forks. Read that the stem from the 98 GSXR needs to be milled down. Does it need to be milled down to match the diameter of the F2's or what portion needs to be milled down?

Before I machined down a stem I'd look for a bearing that fits what you have. You're looking for a bearing with I.D. of the Suzuki stem and the O.D. of the Honda frame. All Balls racing has bearing kits for popular front end swaps and can also help you find sizes that aren't listed. Industrial bearing suppliers can also help.

If you end up having to do the machining route, you'll need a lathe that is large enough for the lower triple clamp to clear the bed. Otherwise, you'll have to press the stem out of the lower triple clamp, machine it, and press it back in. Stems typically have a machined place for the bearing at the bottom, a section of smaller diameter in the middle, a machine place for the top bearing, and then a threaded place for spanner nuts. The bearing surfaces will need to match the I.D. of the Honda bearing.