I removed the camshaft sprocket to get to the piston on a 110cc atv. My problem is I didn't check how the sprocket should be put back on the camshaft. I need to know which way the timing mark (dot) on the camshaft sprocket should be pointing in relation to the cam lobes.

 

I'm not familiar with your engine but I did a google search and found this.

Set 110cc timing

hope it helps


Ram50

 

That link doesn't answer my question. I want to know where the timing mark ( dot) on the camshaft sprocket should be pointing when reinstalling it back on to the cam. I removed the camshaft from the head and i don't know which way the timing mark on the sprocket should point in relation to the cam lobes.

 

Let me make myself clear. The camshaft has been removed from the motor and it is sitting on my workbench. So what I did is I removed the three bolts that hold the camshaft sprocket to the camshaft without taking notes of how the sprocket should go back on the camshaft. I need someone to tell me which way the camshaft sprocket timing mark should point in relation to the cam lobes.

 

These Honda knock off 50-110 cc engines are mostly the same. Here is a link to a service manual.

http://www.mastertechsports.com/BAJA...e%20Manual.pdf

 

Here is another good link for a 90cc ATV.

http://www.mastertechsports.com/BAJA...e%20Manual.pdf

 

ahhhhhhh I see said the blind man....... I'll see what I can find I was going in the wrong direction... my bad. I take it that the sprocket and cam are not keyed then ?

 

Both those links are great!!!

Thanks for that...

 

I'm trying to visualize this... And I should say I have no mechanical experience on this engine...

But you then only have three possibilities (for three bolts), right? So if you align the TDC mark on the crankshaft, crank the cam over until both valves are closed, *and* the camshaft sprocket can be mounted with the mark aligned, *and* the valves are closed for many degrees of rotation on either side, you should be there. I think that is right. The only other possibilites are with the cam out plus or minus 120°, which would have one of the valves open or really close to being open, and the marks aligned.

The intake and exhaust valves are both closed for most of the compression stroke, and most of the combustion stroke. The marks are aligned at TDC on the compression stroke. Thus it should be unambigous (I think) where both valves are closed, and not anywhere close to being open.

 

ahhhh crap thats right...... its a three bolt pattern all three bolts should only line up one way.