Demorgan
XS650 Enthusiast
Hi! i have just finished rebuilding my engine from barrels upward and installed in frame, and was just making some final checks when i got suspicious about the timing, specifically the points opening and closing looked all wrong... upon closer investigation, it looks like the cam is 180degrees out... ie, the little locating pin that drives the advance mechanism and points DOWN when the left piston is at TDC on compression stroke..(and upward at TDC exhaust stroke) i KNOW that when i installed it i made sure it was upward and the pistons were at TDC, and surely its the cam that decides where in the cycle each piston is...therefore if the cam was right when i put it in, (ie, the notch pointing upward) and the left (and right) piston at TDC why is it not right now?? IF i had accidentally put it in upside down while engine is at TDC, it would mean the valve timing would be all out, but it isnt, they open and close all at the right time, its just the points are closing at 180degree from the 'F' mark on the rotor... am really confused! help!
i really dont want to have to open it all up again!!
and yes, i have searched for similar treads, which is why i am able to confirm the position of the cam by the driving pin behind the advance mechanism...
thanks!
i really dont want to have to open it all up again!!
and yes, i have searched for similar treads, which is why i am able to confirm the position of the cam by the driving pin behind the advance mechanism...
thanks!