2002 300ex timing chain question - Honda ATV Forum
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post #1 of 4 (permalink) Old 12-12-2010, 08:31 PM Thread Starter
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2002 300ex timing chain question

I bought a used 2002 300ex for my son. He has been unable to ride as of yet due to some repairs that need done. After completing all repair we got it running, and it seems to run great, right up until the time you shut it off. It seems every time you shut it down the timing chain jumps off the sprocket. The tensioner is out the whole way, and the chain "seems" tight, but not sure how tight it should be. I'm more of an auto mechanic. I'm thinking the chain is just stretched to the point that it is jumping, but also thinking maybe the tensioner is weak.

I was wondering if anyone else has had this problem or seen this before with a 300ex.

Any and all help is greatly appreciated.

Thank you,

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post #2 of 4 (permalink) Old 12-12-2010, 08:45 PM
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Welcome to the forums... I would say you are on the right track the chain may be stretched How do you put the chain back on? do you take the rocker cover off and put it back on? How did the cam bearings feel? any slack and it would cause the cam to wobble a little throwing the chain. your guides may also be worn too along with the tensioner

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post #3 of 4 (permalink) Old 12-12-2010, 08:54 PM
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Welcome to the forums. If the tensioner arm is coming all the way out as far as it will go, the chain is stretched.

Most 4-wheeler problems are caused by a loose nut connecting the handlebars and the seat!!

You only need two tools in life -- WD-40 and duct tape. If it doesn't move and should, use the WD-40. If it shouldn't move and does, use the duct tape.
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post #4 of 4 (permalink) Old 12-13-2010, 05:32 PM Thread Starter
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Thanks guys. Too put the chain on, Ive been removing the cam, placing the crank on the "T" timing mark, getting the chain on the crank sprocket, the installing the cam, followed by reinstalling the tensioner. The bearings feel fine, imo. So I guess I'm going to order a new chain, and possibly a new tensioner. I really havent looked much at the guides themselves, as I never really thought of them being worn.
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