Cam timing basics made easy
Posted November 01, 2008 - 04:48 AM
Posted January 15, 2009 - 10:28 PM
Posted January 15, 2009 - 10:34 PM
Posted January 16, 2009 - 07:51 AM
The biggest mistake people make is setting the timing with the chain tensioner out, and never rechecking it after putting the tensioner back in. Without tension on the chain, it will slack slightly between the cams. When the tensioner is put in it takes up this slack and the intake cam will roll backwards slightly, often revealing that the timing is actually off by one tooth on the intake cam.
Below is a Grayracer post I copied to a word doc. and actually placed in my manual... it explains this and gives a simple procedure for avoiding it:thumbsup:
[COLOR="Navy"]The next thing that must be looked at in timing cams is that the crank can turn nearly 10 degrees without moving a cam if the tensioner is off the engine. When you think you have the engine timed, rotate the crank backward until it starts to move the intake cam, then manually rotate the exhaust cam back until it draws the chain tight, and then do the same to the intake. After that, rotate the crank forward until it arrives at TDC again. This will pull both cams into the actual position they would be in were the engine running, with the front and top runs of chain drawn tight. See what the marks look like in that position. Not doing this screws a lot of guys up.
Posted January 18, 2009 - 05:28 PM
Posted January 18, 2009 - 07:45 PM
Posted January 26, 2009 - 09:10 PM
My wr450f was a running bike until it started discarging coolant from it's over flow hoses, and I mean ALL the coolant. replacing the head gasket should have done the trick but now it won't fire at all...it has all vital components (fuel,oil,air,spark) but still cannot stat...
Am I missing something???