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Author Topic: Tore down the motor again today  (Read 1069 times)

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Offline Sweep

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Tore down the motor again today
« on: January 24, 2008, 02:58:22 PM »
Indeed the cam tensioner is not where it should be on the outside of the timing chain but appears to be on the inside but I cannot tell for sure until I get the cylinder head off, which is a job for tomorrow.

Because of this, what I thought was cylinder 1 TDC as indicated by the crankshaft was actually 10 or so degrees off at the cam.  Is that enough for me not to be able to start the bike?
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Offline scondon

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Re: Tore down the motor again today
« Reply #1 on: January 24, 2008, 03:56:36 PM »
 I am not sure if you CAN install the cam chain roller incorrectly, but if you could I imagine it would make a lot of noise as the cam chain ate through the metal housing. It would only make your chain loose so the question would be "can a loose cam chain prevent my bike from starting?" and  I would think the answer to be no.

  As far as the cam being off 10 degrees according to the crankshaft, I'm curious as to how you went about measuring this. Was it by eyeballing the keymarks on the cam? If they are not parallel to the bearing caps does jumping a link on the cam sprocket fix things? Usually the keymarks don't line up exactly anyway but are a general reference point.

  The TDC mark on the cam crankshaft is also a general reference point and can sometimes be a bit off from "true" TDC. A piston stop and a degree wheel can tell you where true TDC is on your engine.

   If the head has been decked and you are installing a performance cam then consider getting a slotted cam sprocket and degreeing in your cam. The cam timing can be thrown off a bit depending on how much the head has been decked so a slotted sprocket may be needed if you want to bring it back to spec.
« Last Edit: January 24, 2008, 03:59:34 PM by scondon »
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Offline Sam Green Racing

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Re: Tore down the motor again today
« Reply #2 on: January 24, 2008, 04:11:07 PM »
How far is it from Jersey Shore to Boston ? ::) ::) ::) ::) ::) ::)

Sam. ;)
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Offline Sweep

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Re: Tore down the motor again today
« Reply #3 on: January 24, 2008, 04:14:26 PM »
Quote from: scondon on January 24, 2008, 03:56:36 PM
I am not sure if you CAN install the cam chain roller incorrectly, but if you could I imagine it would make a lot of noise as the cam chain ate through the metal housing. It would only make your chain loose so the question would be "can a loose cam chain prevent my bike from starting?" and  I would think the answer to be no.

  As far as the cam being off 10 degrees according to the crankshaft, I'm curious as to how you went about measuring this. Was it by eyeballing the keymarks on the cam? If they are not parallel to the bearing caps does jumping a link on the cam sprocket fix things? Usually the keymarks don't line up exactly anyway but are a general reference point.

  The TDC mark on the cam crankshaft is also a general reference point and can sometimes be a bit off from "true" TDC. A piston stop and a degree wheel can tell you where true TDC is on your engine.

   If the head has been decked and you are installing a performance cam then consider getting a slotted cam sprocket and degreeing in your cam. The cam timing can be thrown off a bit depending on how much the head has been decked so a slotted sprocket may be needed if you want to bring it back to spec.

I was eyeballing it and it wasn't off all that much.  Upon further thought I brought the engine to tdc AFTER removing the tensioner so it's moot.  I do have the slotted cam sprocket and all the 836 goodies from dynoman.

OH!  and there doesn't seem to be a tensioner in there at all anymore.  I'm sure I installed it too, I'm be having some nightmares about this tonight.
« Last Edit: January 24, 2008, 04:18:09 PM by Sweep »
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Offline Sweep

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Re: Tore down the motor again today
« Reply #4 on: January 24, 2008, 04:15:23 PM »
Quote from: SamCR750 on January 24, 2008, 04:11:07 PM
How far is it from Jersey Shore to Boston ? ::) ::) ::) ::) ::) ::)

Sam. ;)

Not far by Amtrak :)

I'll get through this one way or the other and be better for the experience.
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Offline cbass*gxc

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Re: Tore down the motor again today
« Reply #5 on: January 24, 2008, 04:19:51 PM »
Quote from: Sweep on January 24, 2008, 02:58:22 PM
Indeed the cam tensioner is not where it should be on the outside of the timing chain but appears to be on the inside but I cannot tell for sure until I get the cylinder head off, which is a job for tomorrow.

I did the same thing when putting mine back in but decided I would bring the laptop into the garage and look at the manual while I put it back together.
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