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Valve Timing Issues: 83 XL600R

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Hello all,

I had the connecting rod replaced on a 83 XL600R with a hotrods rod. While assembling the engine I couldn't get the valve timing set right. No matter what I did it was a half a tooth off. I tried a different chain, flywheel, and sproket still half a tooth off. :lol: The timing chain only has 50 miles it. Also, This is not the original crankshaft the original was toast.

Is it going to make that much difference if it is a half a tooth off? Wouldn't the ignition timing be off as much? Since the gears are on the same spline on the crankshaft.

Thanks,

Mark

Edited by kmequint
added information

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Have you had the bike running yet with the new stuff in and the timing set up with the half tooth out.?? Is the key that holds the flywheel on installed and holding everything correctly when bolted up.?? To be honest I wouldn't be worried too much about a half tooth out.,I've said before that I believe there's a little room for leeway due to the floating nature of TDC of the compression stroke,,sometimes things just don't line up dead on..,Others may disagree..A full one tooth would be a bit of a concern,,two teeth out would be a "look into it situation",,ie get it fixed..

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Horri,

I have not tried to run it yet. The engine is still sitting on the work bench. The woodruff key is in place on the flywheel. Well, if I do leave it as is, the timing marks on the cam shaft line up with the "F" mark on the flywheel. Is that the way you would leave it? Or in another position? To make a long story short this is the third time I have had this engine a part. I am a little gun shy. The next time I tear one apart I will know what to look for. :lol:

Thanks,

Mark

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Are you sure your lining up the "T" on the crank and not the "F" ? If your on the the "T" then have someone hold the crank in place with a socket so it doesn't move on you, when you line up the cam gear marks with the head, because of stretch, they may not be exactly parallel, but sould be damn close, if off at all the front mark on the cam chain gear should be the one higher up than the rear mark as that is the result of stretch

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Oh yea also make sure you have the chain pulled tight on the front when checking let the rear be the slack side.

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It's got to be on the "T", right on it.... then set the gear with the front mark the higher of the two if need be because of stretch, this with the front of the chain being pulled tight. I would not time it to the "F" as it is now.

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notice in your pic of the crank the marks are not lined up right on, when you line up the "T" it has to be right on the case mark then set the cam gear, the smallest move down there is alot on the cam gear.

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thumpharder,

In the pictures the chain tensioner is in place. The chain only has 50 miles on it. Could there still be any stretch? With the original crankshaft everything lined up perfectly. However, the rod was wore out.

Mark

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yea I see the tensioner is there, I don't know why it would be off so far,just try it once more making sure all is lined up right on on the crank, 50 miles is not much but there will be a little stretch after that many mileand over time it will stretch a little more

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Can you take another couple of pictures of the Crank directly on the T and the Cam marks when you have the T lined up,,ie set it to the T (lock the socket so the T doesn't move) then remove the chain and sprocket and reposition it as close as you can get..,Need a look at how far out your marks are out up top...,

Either that or just give us another couple with it on the T and the cam marks as they are then,,,at the moment you're on the F,,shift it to the T and photos,,

Edited by Horri

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Your good, that is from the stretch I was talking about, but the front mark should be the higher of the two,not the rear,is that with the front of the chain pulled tight?

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that is as good as your going to get, chain stretch, that's all

and by the way those channel locks are awfully clean.... those aren't just to look at you know

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run the engine around a couple times with the socket on the crank and look at it again, just to make sure all is good, as long as T is on the mark and that is as close as it gets, your ok.

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Thanks Horri and thumpharder for all your help. Im going to button it up tonight. :lol: Going out of town for the week won't be able to finish it until next week. :) However, before I start it I will turn it over by hand just in case there might be piston to valve contact. :banghead:

Mark

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anytime,whats a forum for if not to help and look for help?no that won't happen, it's just good practice to run it around a couple times to double check timing, ride that thing.

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