The last time I rode my quad I was doing a few launches and ran into some problems. I started hearing clunking when taking off but it was just in 2nd gear when taking off then seemed to smooth out. I let it sit for a minute and just kinda looked everything over. I tried it one more time and it did the same thing. I stopped and then tried to inch my way to the trailer and the clutch would engage and then slip and didn't want to push the quad at all. The clutch lever seemed to be harder to pull also.
The setup is a 10mil cub, 2 thru 5 override, lockup, hinson billet basket, aftermarket clutch plates and the rest of the clutch is stock. When I pulled the clutch apart this is what I saw. some metal shavings in the basket and some scoring on the back of the clutch boss. I bought this motor used and complete except for the hinson basket, which I installed. I haven't rode this setup much, but last summer when I did, I was hearing the same clunking noise when launching and I thought it might have been chain slap and skipping teeth on the sprokets so I got a chain tensioner. The next time I ran it, I didn't seem to hear the clunking, but now it's back.
Any thoughts on what might be going on, or maybe some of you might have run into this same problem, input would be appreciated.