Can anyone help? Just rebuilt my 04 yz450 with main bearings timing chain piston etc which went together well, but! the bike has a weight welded on the flywheel which covers the timing mark. I've found TDC with a dti gauge and marked the flywheel, set the cams with dots on head face and all lined up well but when you turn the engine over the piston and exhaust valves touch. I can get the bike to run by lining things up with the piston 5mm BTDC but is this right ? My question is: is the standard flywheel mark actually at TDC or am I doing something wrong?