1996 xcr sp 600 build/questions

Not sure if this is the correct section to post under, just looking to post updates and ask questions along the way. I recently picked up one of the despised 1996 xcr sp 600s for 600 bucks for something to tinker with and try to make trail worthy. Only 2800 miles and 125 psi in all cylinders, really clean sled. Like every other one this sled is a dog off the line then screams on top end. So far I have installed 350 350 and 330 mains, needle on 3rd clip, 40 pilots, and drilled out pilot bypass and air screw .5 turns out. It was running crazy rich prior. I have purchased epi black spring for the primary and red for the secondary (I hope this is equivalent to the olp hsp white secondary if anyone could verify that would be awesome), hot seat z weights and 38 helix are on the way. Currently has stock gearing 21/35. First question I have read to switch to a 39 tooth on the bottom, can I install this without having to monkey with the chain? Second if someone could explain to me how to set belt sheave clearance that would be much appreciated as well.


Thanks, Josh

1996 xcr sp 600 build/questions