I was just out attemping to adjust my valves, was hearing ticking ever since the cam install. So I lined up the mark "l" which is right after the "H" and found that the intake valves had play but the exaust valves didn't spun it over again and found niether had play. I put an extension down the spark plug hole and found that when the "l" was lined up the piston was nowhere near TDC, correct me if I am wrong but once that mark lines up, the piston should be at top dead center. How could this be?? Thanks
Terry

 

You have to watch the valves when you turn the crank. You want the "I" mark the first time it comes by on the compression stroke. All the valves will be up. If the exhaust valves are down then you go one more turn to get them all up. Make sure you are only turning counterclockwise. If you go past, keep going till it comes up again, do NOT go back.

 

Thanks for your response, This is exactly what I did, I was able to bring the piston to TDC on the compression stroke by putting an extension down the spark plug hole and then there was sufficient lash on the valves, but the marks on the flywheel were nowhere close to lining up, when the "l" lines up this means the piston is at TDC regardless if it is on the exhaust or compression stroke, or am I missing something here?? Might have to crack out the service manual and see what I can find. Thanks.
Terry

 

I'm not sure...I had the same problem when I adjusted my valves. It seemed as I could only get TDC every other turn. I could stop on the "I" mark and the exhaust valves would be down but the next time it came by everything would be up. As far as your mark not lining up when you were at TDC, could that be a result of your engine mods? Isn't there a longer stroke on the 686? Mine is stock so I don't know.

 

The stroke is the same just a larger bore, I just had the top end apart, I would not imagine that it could be related. Thanks.
Terry

 

On a 4 stroke, the cam goes 1/2 speed of the crank. So every other tdc is the wrong one.
When you installed the cam chain...did you follow the procedure in the service manual for lining up the marks?

 

Fairly confident that it was installed correctly, but even't if it wasn't I think my problem may still lay in the bottom end, my problem is that when I know the piston is at TDC but the marks on the flywheel do not line up, I havn't had the bottom end apart so I don't know if the flywheel with the timing marks can somehow spin on the crank or if it is splined or keyed to the shaft (ie possible woodruff key failure??). Plus my machine wont start which leads me to believe that the pick up is read off the flywheel allowing the ignition timing to be off. Now if someboy knows otherwise your input would be great, thanks.
Terry