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XR200 valve timing question

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I just re assembled my XR200 engine. I followed the steps in the manual to the letter. It says to:

Turn the flywheel until the "T" mark is lined up with the reference point in the window.

Make sure the piston is at TDC.

Make sure the camshaft is (aparently, according to the pictures) is on the compression stroke (Valves closed).

Align the cam sprocket "O" mark with the groove at the top of the valve cover.

I did all of this. There's one problem though- when eveything is aligned properly, if I turn the flywheel another full revolution, then the cam timing gear is 180 degrees out of phase (1/2 turn). The T mark is still aligned after oen full revolution, but now the camshaft is opening one of the valves and is 1/2 turn wrong.

The "O" marker is at the bottom of the cam gear, instead of at the top. Another full revolution of the flywheel and the cam is once again properly aligned. During either revolution of the flywheel, obviously, the pistonis at TDC both times. I have tried trying to start it with the cam screwed to the timing sprocket both ways, in phase and ut of phase, and not so much as a sputter.

It is getting a spark, and after a few kicks the spark plug has fuel on it. Can anyone tell me the proper procedure for valve and ignition timing during initial re assembly? My manual is less than helpful.

Any suggestions are appreciated, thanks!

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Your timing is correct. The camshaft turns half as fast as the crankshaft, allowing for four strokes per power cycle. Therefore, it will be out of phase compared to the crankshaft every other cycle. The XR-200 is set-up so that it only fires on the compression stroke since the ignitor coil runs off of the camshaft. As long as you have it installed correctly per the manual, it will be close to the correct timing. I don't think you can put the ignitor in upside down anyways.

I would suspect something wrong with your carb causing the engine to flood. Try cleaning the carb and see if it will run then. Good luck!

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What I mean is that I can keep the camshaft stationary, while I rotate the flywheel, and then put both cam sprocket bolts back in, and it will be in phase eventually, no matter hwere the timing marks are at. I also did clean out the carb before I put everything together. I am starting to want to put this bike back into the lake I originally drowned it at. :thumbsup:

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I have tried everything. I cleaned out the carburetor twice, tried every possible combination of timing, even tried a new spark plug and a new tank of fuel (twice). It doesn't so much as pop.

It gets a small blue spark sometimes, and it seems that the plug isn't as covered with fuel as it should be?? I adjusted the valves, etc, it has great compression. I could get a working CDI unit off of ebay for 60 bucks, but what if that isn't it? This bike was more reliable when it was worn worse than any engine I have ever seen. With all the effort I have invested into it I am about ready to pump it full of lead, just to relieve some stress.

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Sand your grounds, so it's has a good connection. And make sure your spark plug cap isn't worn out. Otherwise, see if you can get a stator off ebay.

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Thanks. I will try that. However, I did use an alligator clip to ground the ignition assembly to the cylinder, and it made no change. I also used a wire and alligator clip to mimmick the spark plug wire and cap, and there was no change.

The stator coil checks out find resistance wise, as does the pule generator as well as the ignition coil. There is something simple and stupid that is keeping this bike from running. It shouldn't be the electrics because they were working fine before I drowned the bike. I will definately sand everything and let you know what happens. Thanks again!

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Alright, I soldered every wire to every connector, and sanded the grounds real good. It seems to me that it has a nice fat blue spark the first 1-3 kicks, then it gets weaker, and sometimes gets fat again. Is this a symptom of a bad CDI?

Also, it is still intermittent, I am not sure if I am just not grounding the plug right, or what. It's odd that sometimes the slightest turn of the flywheel will produce a spark, though. Does anyone have a description of the spark they get by kicking their XR over? I think the spark on mine should be sufficient to start the bike, yet, nothing.

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