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BFLee

Motor noise after timing the cams

11 posts in this topic

I finished putting my bike togather last night after do the BK, gray wire, and YZ timing mods. I started it this morning before work to see if all was good. It started first kick, but was making a solid knocking noise at idle. I shut it off after about 10 seconds when the noise didn't stop immediately. I couldn't do any more checking because I was late for work.

The motor definitely didn't make this noise before. All tools and parts were accounted for before valve cover went back on, I'm pretty sure nothing went in the motor. I checked the valve clearences after the timing change and they seemed right on.

Any ideas or similar experiences? Could it be that the oil pressure had just not come up yet?

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Yikes!!

It sounds as if your timming chain skipped a tooth while you were lineing up your timming marks. My recomendation is to follow your book very closely, put it back to stock, run it to make sure it's good, then do the yz timming all over from scratch. I know it's a p.i.a this way but better safe than sorry.

SoCal

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Agree with above post. Also, make sure you wind the cam chain adjuster back before you bolt it back in. That can cause big problems as well.

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Did you remember to retension the timing chain tensioner when you were done...if not it may have slipped when you started her up. Make sure you get this part right if you redo (worth checking now also): Use a screwdriver to wind fully in and it well then lock itself automatically out of position. Do this during the timing change and then when everything is hunky dory, unwind it and it will snap back into correctly tensioned position. First time I did the timing mod I didnt do this winding procedure and greatly overtightened the timing chain when reinstalling : when you remove & reinstall the timing chain tensioner without winding it in you end up reinstalling it with max chain tension which is wrong

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Do a search on my user name and read my saga of noise after a valve adj. Turned out I didn't get the timing marks set right and the noise was scaring the crap out of me. I didn't figure out what I had done until the second time I checked the valve timing marks.....

Brian

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Everybody, thanks for all the tips and suggestions.

I take great pride in my ability to take care of my own machines, remodel my home, build computers, and generally do just about anything as well, if not better than as I could pay to get it done. I am very meticulous. Every part that comes off is cleaned, every nut and bolt is torqued to spec. I will spend a little extra to get the best parts.

Now it is time for me to come clean.

I timed the INTAKE CAM.

I guess I got lost in the details and lost sight of the big picture.

All is well. I rode the Prarie City GP on Sunday and the bike ran like a top.

So remember TT kiddies. The Exhaust cam is the one closest to the front wheel , or the one by where that tail pipe thingy is sticking out of the motor thingy.

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On the subject of motor noise after cam timing, I noticed some noise comming from my bike. It sounds like the carb slide rattling at idle. I never listened that close prior to the timming change but I don't believe it was there before.

I am sure it is from the carb. I suspected that w/the YZ timming the bike is breathing harder making the slide rattle. Has anyone noticed this on their bike?

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Originally posted by BFLee:

Now it is time for me to come clean.

I timed the INTAKE CAM.

I guess I got lost in the details and lost sight of the big picture.

So remember TT kiddies. The Exhaust cam is the one closest to the front wheel , or the one by where that tail pipe thingy is sticking out of the motor thingy.

:) 10/10 for Honesty anyway, I doubt you've been the first, and probably won't be the last! :D:D

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Originally posted by Guy:

:D 10/10 for Honesty anyway, I doubt you've been the first, and probably won't be the last! :D:D

Well, I know he wasn't the first because I did it before him - unintentional in my case. I just screwed up - wasn't trying to convert to YZ timing :)

Brian

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