which material

I am going to swap in a 93 gsxr750wp swingarm next winter and I only need bushings to use the stock 650 spindle in the gixxer needle bearings. What kind of metal should the bushings be? Sintered bronze was what I was thinking, am I wrong? Does it need to be steel?

Bdog; It's been my experience that needle bearings like a hardened material to rotate around. The factory set up's I've seen use a case hardened steel material. How hard it needs to be, I don't know. If you use a soft material like sintered bronze, I'm saying the needle bearing will eat it alive. You could probably find a sleeve with the correct O.D. and have a machine shop shorten it. Let us know how it goes, ride safe, Steve

OK, I'll let you in on a little secret if you use the inner bearing races from a '86-'88 Gsxr1100 they will adapt your bearings from the newer arm to the 16mm axle that the Kz650 and 900/1000s use. It's that easy. The bearings are the same for the early 1100's and your arm but the early 1100s had the same diameter spindle as the Kz's do instead of the larger axle. Hope this is and easy fix to you.

Later, Doug