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1987 xr100r no start issues

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I bought an 87 xr100r for my son for christmas because he wants to learn how to ride. We went to pick it up and it started right away but their was no place for me to ride - the bike sounded ok while running so i bought it. I got it home and it started 1st kick and i took off around the parking lot of my auto shop and it felt like a terd no power but idled fine (kinda ran like a vehicle with the timing off a tooth) pulled carb and soaked and cleaned and wired all the jets and reinstalled it and it has not started since. I pulled the spark plug out and noticed locktite on the threads and upon further inspection.... well i had to helicoil the head - when you kick it over every 4th kick it would backfire and then again on the 6th kick it would do it again. Pulled the valve cover and the flywheel cover and checked my timing marks and they were off so i pulled the flywheel and the keyway was sheared and i took a toyota truck keyway and ground it down to fit the slot and reinstalled the flywheel and the chain was 2 teeth off from timing marks lining up so i pulled the cam gear off and rolled the chain over 2 teeth and that lined to O on cam up with flat spot on cross bar behind gear and T on the flywheel lined up with mark on upper side of case but now i have no compression. I moved the timing back to where it was and still no compression so i moved it back again. The crank sensor (mounts to right of flywheel and reads flywheel rotation) only has 1 bolt in it but i think it is reading ok because i have good spark. Someone whom should not be working on anything has been into this bike before. I think i now have a bent intake valve because when i put air into spark plug hole i have air coming thru intake all the time . I am not a motorcycle technision by any means but am i on the right track?

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Yep. I think you found your problem. Good work :busted:

So now what to do? How's the bottom end? Got any up/down motion when ya move the crank?

Is the bike in decent condition otherwise?

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Thanks, im taking the head off today to see what all i need. Any do's or dont's come to mind of things to look for?

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Overall the bike is in descent condition no play in the crank and no visible oiling issues. I am going to replace the stem bearings and the swing arm bearings but overall the bike is in pretty good shape.

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Overall the bike is in descent condition no play in the crank and no visible oiling issues. I am going to replace the stem bearings and the swing arm bearings but overall the bike is in pretty good shape.

I'd say you're right on target to some future fun. :busted:

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The best i can tell i am going to have to pull engine out of the frame to remove the head due to clearance issue or is their a trick that someone might want to share?

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Well i got the motor on the bench and got it apart and somehow a shard of metal from where we drilled out for the helicoil was stuck to valve seat. Valve is true so i am reusing it after i lap it back into the seat no visible damage and it closes off and holds carb cleaner in intake side of head. Anyone know the adjustment on the valves so when i put it back together i can adjust them properly?

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Not sure...I used to use a matchbook cover. Basically, I did them by feel, and the sound. If it's a quiet runner, and it has some clearance, you're in the ballpark

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The best i can tell i am going to have to pull engine out of the frame to remove the head due to clearance issue or is their a trick that someone might want to share?

No need to pull motor, just remove front mounts and upper rear mount and it'll tilt forward enough for removal of head.

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