Cam phasing/ cam chain issue.

[Motornoggin]

Just set the valve lash and am in the process of replacing the cams. According to the book, the exhaust cam should be in a certain position with the cam chain pulled tight. When I do this, the chain is exactly on half link (one tooth) off. However, if I correct for the tooth, then the chain is again, one half link off. It's as if the cam chain is one half link too long. If I place the exhaust cam sprocket timing mark where the book says it needs to go, with the pin count as the book says, the crank is no longer at TDC. Very difficult to articulate what is going on, but I can't seem to get it in the correct position. Looking for an idea.

[MAN OF BLUES]

when you get them in, caps pulled down, and install the tensioner, it should line all up.

[Motornoggin]

Ok, but to what end do I set the bias before I button it up? That's where I'm having issues. No matter which side I put it, it's off when I tighten it all down. I'm either not at TDC, or, I can't get 30 pins between sprockets and get the timing marks to line up.

[Motornoggin]

The draft in the book shows that when the crank is at TDC, the chain should be between links (when viewed at the cylinder head surface) when the exhaust side of the chain is tight. Mine is in the middle of a link. One half link too long (or, conversely, too short). If I count 30 pins and install the intake cam, the timing mark is above the cylinder head surface, not in line with it as the books says it needs to be. If I align the timing marks, I get 31 pins.

[motocopter]

On page 5-19, this bullet seems to be key:

* "Pull the tension side (exhaust side) [A] of the chain taut to install the chain."

Then get the 30 pin count back to the intake cam. Again, be sure there isn't any slack in the chain between the ex cam and crank. To do a quick check push in on the chain guide where the tensioner mounts. Do keep the crank in the correct alignment.

Another quick check would be to verify the cam lobes of the TDC cylinder are pointed up and out pretty-much symmetrically.

[Motornoggin]

Yup, I understand that. After completely buttoning it up, I think the chain slacked enough while taking it apart that it skipped a tooth on the crank. Still one half link off. Taking it apart again so I can get it right. I'm wrapping my feeble mind around what has to happen to get it all in phase/aligned. Thanks for the replies, keep them coming with anything else.

The cams are in phase with each other, but they are both off in regard to the crank.

[Motornoggin]

Ok. Got it. Everything is lining ok now. Sheesh, still not quite sure why it didn't in previous attempts. Thought I was going a bit bonkers.

Thanks for the replies, if anything it made me stop and think about it for a minute.

[motocopter]

Good news!

[MAN OF BLUES]