Hi everyone, I'm new here and I have a few questions regarding my 400ex. I bought it and it was already bored to a 440, I prefer the 416, but it's fine. Bought it anyways, ran good, and then I blew it up. Something made my intake valves go through the piston. No big deal right? Wrong. I got new valves, piston, valve seals, rings, head gasket, wrist pin, everything. Put it all in to spec and she run great. Started right up and went like a dream. I had about 4 hours on the rebuild, still breaking it in, going light, and I took a rest by a brook. Go to start her again about 20 minutes later, starts up, but the ticking somehow went from like a 3 to an 8 really fast. Shut her off, and she wouldn't start again. Took her apart, and my intake valves are bent and stuck open. Why? I think it's my rockers, because they seem a bit worn, and I just picked up a parts machine for the plastics, so I'm putting the rockers from that in the good one. No hole in the piston, but the cam is about 1/4 of the way off of timing as well!! The chain is tight, and everything seems fine with that, I just don't know why it would skip timing and bend the valves again. Hoping that when I put the rockers in it might help. Aren't the chain tensioners on these faulty? I think I heard that somewhere. I have one off of the parts machine I could try. Any help would be greatly appreciated. Thanks!