So I took my bike to the mechanic to replace the piston and rings. He took it all apart and recommended new crank bearings as well. No worries, I figured it was time for the bearings, cam chain, water pump, etc. I picked up my bike last Friday so I could break it in last weekend. I had a hard time staring it, once it started it didn't idle well, on decel it would pop pop pop and when pulling out of a corner it would pop and completely shut off. Took it back to him to check the valves and timing. He said everything was in spec, I started it at home and rode it down the block ( but not enough to really see if it was ok) and it was "ok". I went out this morning to try it out in a Hare scramble and I barely made one loop. I was so pissed! It was doing the same thing.....I was so frustrated and tired from trying to kick the bike over I just gave up when I came in. I need some advice on what you guys think I should look for. I'm reluctant to take it back to the tech that worked on it and don't mind wrenching myself. Please help.