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1982 honda xl 100s timing chain issue

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My daughter's Enduro jumped time due to a worn chain. We have it all back together with all new timing parts and valves but the timing marks are not lining up like it's supposed to. It says to line up "t" on the flywheel with the bolts on the cam gear parallel to the valve cover mating surface  but they are off a few degrees. They do line up on the "f" mark. Any suggestions?

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If the timing marks on the fly wheel is on point then it looks like you’re off a tooth. 
Pose the question in the bike specific or vintage forums. You’ll get more information there. 

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Thanks, moving it a tooth puts it off that much the other way. I'll try posting in another part of the forum. 

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Posted (edited)

It is not uncommon for this to happen. Engine timed properly, wrapping the chain over the cam sprocket while pulling slack out of the non-tensioner side, so that all slack is on the tensioner side and the cam still is slightly off level with the head surface. 

If it's going to be 1/2 tooth off, put it on the non-tensioner side. As the chain breaks in/wears over time and the tensioner compensates for wear, it will have pulled the sprocket level with the head when checked again at some point in the future.

Example: if the tensioner is to the right in the picture above, then if you have everything set/timed right and this is how it ends up, I'd button it up as shown. If you put the 1/2 tooth off to the right in this picture and it is the tensioner side, then with chain break in/wear, checking later with the engine timed right, you'd find the sprocket pulled off away from being timed with the head more than 1/2 tooth.

Edited by Trailryder42

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Thanks, I'm glad to hear it isn't an isolated incident! That was pretty much my first though, run it on the advance side so as it wears in it will even out, but I wasn't sure how sensitive the timing was on this. I usually work on jeeps, you should see how much slack a 4.0 will get in its chain after 300k and will still run pretty damn good!

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I agree for a play bike it'll be fine. Now about the Jeep, at 300k miles you'll develop an oil leak from the cam chain wearing though the tin cam cover but yes if you keep oil in it, it will keep running along.

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Thanks for the help guys, I finished her up today and she is running great! I am the hero of the day to a 12 year old girl. Had her help with a good amount of it, first of what will be many more father daughter projects to come.

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That's cool, my girl is 26yrs old now, we ride together alot. She been wanting to learn for a few years now, I try to involve her with the wrenching as much possible, she can do her own oil and filter changes now, o-hum as they get older we see them less and less, enjoy it while you can.

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