I got everything back together and ran the engine on the buggy. It runs fine but if I'm starting under a lot of load (WOT on a stopped buggy) there is a clunking sound. I thought it was the chain slipping at first but the chain is tight. Any ideas what it could be? I tried to take video but I still can't tell what is causing it. It doesn't do it when going fast - just under a lot of load.
Here's the video -
https://youtu.be/sqClUO7yoPQ