Top dead center?

[n811]

I was trying to adjust the valves on my 400ex and the manual said with the engine at top dead center I would be able to move all of the valves. Well, I looked in the hole with the mark on the spot and can only move the intake side. So the manual says that the engine is on the exhaust stroke, rotate it again. I did - and now I can only move the exhaust side. How can I get it to where I can move all 4 valves?? The manual also said - if the right one was sticking, that the decompressor was jammed - and to shake the engine back and forth to unstick it... how do you determine which one is the "right" one? And, is this why I can't move all the valves??

[Old Head]

Did you check them with a feeler guage because it is kinda hard to tell if they move by hand, its possible if your used to checking. remember they are only moving thousanths of an inch not just slopping around in there. How you tell whats right and left is, when your sitting on the bike the right is your right. There is a picture in the front of the manual that shows this.

[dariusld]

I sometimes take out my plug and put a screwdriver in the hole to check for tdc. Careful with the screwdriver, you want sitting on top of the piston not the edge.