Page 3 of 3

Posted: Tue Feb 09, 2010 11:30 am
by BuzZz
It is unlikely the problem is your fresh rings. Not impossible, I guess, just highly improbable. The difference between each side is probably due to the fact that they haven't even had a chance to break-in to the cylinder walls yet more than anything. A small nick or break during installation is possible..... but I kinda doubt it, knowing you, and it wouldn't cause the miss in all likelihood.

So if it isn't the carbs or some other fuel issue (that it really sounds like but has been worked over) then I'm back to pulling straws out of my butt.

This sticky valve business.... the engine runs on both cylinders for a few seconds before one stops and this makes me wonder if a valve is not getting warm and expanding in the guide, causing it to stick open temporarily. The cam will have the power to open it, but the spring is too weak to close it all the way again. The problem could be either a weak spring or a tight valve guide. And this is all just a wild guess on my part....... :dunno:

Posted: Wed Feb 10, 2010 7:25 am
by coffee_brake
All noted...thank you.

I wonder if I shouldn't break the carbs down off the rack and swap 'em, then I'd know FOR SURE before I yank the head back off.