yam 3. It has been a while since I have done a z50 and I am doing this out of memory, so, good luck to both of us.:scream:
First, rotate your engine until the piston is at top dead center. There should be a line on your mag flywheel and one on the case that will line up.
Look at the cam wheel. On one side of it there should be either one or two lines. Install the cam into the head with BOTH CAM LOBES POINTING STRAIGHT DOWN.
Slip the cam chain over the sprocket and line up the bolt holes in the sprocket with the one's on the cam. If there is only one line on the cam sprocket, it should face straight up or straight down. It does nnt matter as long as the cam lobes are pointing straight down. If there are two lines on the cam sprocket, then align these lines parallel with the top gasket surface on the head, rocker cover surface. If the lines don't line up, move the cam chain over the sprocket one tooth at a time until they do line up.
The important part is, both lobes must point straight down and the engine must be at T.D.C. If this is correct, the lines will line up. Also, recommend using a little loc-tite on the cam bolts.
Good luck.
Ol'89r