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If cam chain lets go??

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Old 07-12-2011, 03:52 PM
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If cam chain lets go??

So if I didnt adjust (or install) the manual CCT correctly, what gets broken if the chain skips? Right now it runs on one cylender and blow some blue/white smoke. No mechanical crunching or bad sounds. Do I have to pull the motor to look at it ? What may have happened?
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Old 07-12-2011, 03:58 PM
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Well if it was so loose that it did skip more than a few teeth it could be as bad as a failed OEM CCT.

If it only skipped one or two, it may just be losing power due to the valves opening at the wrong time (retime and fixed)

But white smoke sounds more like a headgasket failure. How were your engine temps?
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Old 07-12-2011, 04:01 PM
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I think that if the cam chain skips, then the valves are out of sync with the piston head. If they skip more than one tooth, this means that they are still open as the piston is coming up (or opening before the piston goes down), and the two crunch each other, causing damage to the valve and possibly the piston.

Sounds like you may have something different, although now you got me a little worried about my CCT adjustment. I just adjusted the initial slack as I didn't trust myself to hear the correct "rattling" when setting the tension.
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Old 07-12-2011, 04:05 PM
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They would have to be VERY loose to allow this to happen though.. I really don't think it is this. (you would have a slapping noise while running prior to it ever skipping a tooth) Unlike the OEM ccts they shouldn't retract on their own.

Was the lock nut not cinched down? That is the only way I could think of it happening after a long trip.
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Old 07-12-2011, 04:11 PM
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No the lock nut is snug. Like I said it was running great, then lost low end power but had good top end on the hiway, then sputtered and got worse so I pulled off.
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Old 07-12-2011, 04:14 PM
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I doubt it is the CCTs then. That doesn't sound like they failed. When they fail it is accompanied with all kinds of metal on metal noise...

It really sounds like the headgasket to me, but I could be wrong.
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Old 07-12-2011, 04:22 PM
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But headgasket would mean oily coolant or milky oil right?
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Old 07-12-2011, 04:28 PM
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Do a compression check if the engine turns over freely and go from there....
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Old 07-12-2011, 04:30 PM
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Not always, depends where the gasket gives up
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Old 07-12-2011, 04:38 PM
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So I guess the related question is do I need to pull the motor or can I dig into it in the frame??
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Old 07-12-2011, 04:46 PM
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You can replace a head gasket while it's in the frame... I'd go with 8541Hawk's advice and run those tests while it's together though.
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Old 07-12-2011, 04:54 PM
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I have had blown HG's on other bikes and they still run, just overheat quick, and what about the smoke? The cylinder would still fire and run (in my experience)
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Old 07-12-2011, 05:46 PM
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I'd pull that rear head right now, especially since it is so easy to get to. You don't want any coolant to sit in there. How does your oil look?
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Old 07-12-2011, 08:10 PM
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You can pull the head(s) with the motor in the frame, no problem.
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Old 07-18-2011, 07:40 AM
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Originally Posted by lazn
I doubt it is the CCTs then. That doesn't sound like they failed. When they fail it is accompanied with all kinds of metal on metal noise...

It really sounds like the headgasket to me, but I could be wrong.

I'm on with head gasket here too, certainly not the tensioners. The reason not the tensioners is because to jump time you'd have to have them turned out so far you'd hear the clatter of the cam drive across a room over the exhaust. As I pointed out in another thread, to get enough room for the timing to jump you'd have to have the adjuster bolt turned out at least five turns too loose. My only concern with adjustment of cam drives when going manual has to do with being too tight. Too tight can break stuff and cause cam journal damage. If it was too loose you'd think a bunch of Keebler's elves took up residence in there beating on stuff with mini-ball peen hammers. The noise would make you shut down the bike immediately if it was loose enough to jump.

Clearly since it was being ridden and running fine I'm thinking cam drive adjustment is out.
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Old 07-23-2011, 10:08 PM
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usually theres no hardcore damage to the piston if it skips time (sometimes there is damage to the head and piston and especially valve guides)... however if it did it wouldnt clear up on the highway... if a head gasket failed or a head cracked you could get smoke and loose idle and low end but may still fire and run better on the highway... generally speaking white smoke is coolant, blue is oil, and black is too rich or not enough compression... hope this helps
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Old 07-23-2011, 10:19 PM
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the head gasket could also blow the other waw and mix the oil and coolant... sometimes you wont get smoke from a head gasket if the exhaust doesnt get hot enough and you complete the work and it smokes like hell...
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