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650L overhaul parts

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I am getting ready to rebuild my 94 650L motor. It came off a bike that did not run, had low compression and a very,very loose timing chain. I looked on here and did the correct procedure to check compression and I still couldn't get it above 60 psi. I also found that the timing had jumped several teeth and I never could get the exhaust valves to have clearance. I did notice that the lobes on the rockers did show wear, along with the cam. The timing chain was so worn I could pull it off once the tensioner was loose.

Now to the question: Since I have to do a teardown what parts do you think I should replace since I don't know anything about this motor? The odo on the bike shows 12,696 miles. This motor is going into a 400 EX frame once I get it done and I am selling the rolling chassis from the bike to help pay for parts.

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12000 is not much but then it all depends on how the person maintained it,,Going by the state of the timing chain I'd say a tear down to the Piston is in order and a measure of crank tolerances..Minimum,,Piston/Rings and rebore, Timing chain obviously,,Tensioner mechanism==> maybe,,certainly the auto mechanisms spring at the least..Maybe the Cam chain guides,,maybe the top and bottom Cam chain sprockets and possibly all bearings ,,who knows what they are like,,Top Cam ones for certain..Rest,,dunno,,Then up to the tappet cover for a possible Cam and Rocker job and the seals and maybe guides..Expensive if you want to be thorough..Oil pump measure and check..Lists kinda endless really on an unknown motor,,

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Wait until you at least take the head off before buying anything. It sounds like it is going to need a cam chain at least and possibly chain guides. Slipped timing chains can also lead to bent valves, so again, wait until at least the head comes off. At that point you will be able to inspect the bore and decide whether or not the jug should come off.

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