ORIGINAL: phattracker

My clutch bell keeps "locking up" on my motor after a tank, or sometime during that tank. I've tried several different shim setups, but none are working. I have a 14t Ho Bao on a OFNA Force .28. The bearings are good. I'd throw new ones in there if they were bad, and when i take it apart to troubleshoot/clean everything seems fine. Upon putting it back together with at first 2 shims in front of bell, worked fine, ran a tank, locked up. Then 1 shim up front, spins nicely, ran a tank, locked up. No shim, spins freely, ran a tank, locked up. What can I do to fix this? Thanks.