Cam chain tensioner removal: Difference between revisions

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==Cam chain tensioner theory==

~~How~~ the tensioner ~~works:~~ The springs push on the push rod, which pushes on the cam chain guide. The ball and retainer assembly, in combination with the push rod and the tapered barrel of the chain tensioner housing, form a ratchet mechanism that allows the plunger to go out but not come back in under normal use.

The purpose of the tensioner is to take up the slack on the cam chain as it stretches with normal use. So it's designed to only move in one direction. The springs push on the push rod, which pushes on the cam chain guide. The ball and retainer assembly, in combination with the push rod and the tapered barrel of the chain tensioner housing, form a ratchet mechanism that allows the plunger to go out but not come back in under normal use.

The negative part of all this is that when the tensioner goes, the cam chain can slap around within the engine, tearing off bits of the plastic that are there to help guide it and protect the metal... which then float around in the engine until they get stuck somewhere or do damage. The chain can also jump teeth, in which case the timing is off and the bike runs terribly, or you have that unhappy valve-to-piston contact. So, if you have a (usually consistent) ticking coming from the upper right side of the motor, and you know the valves to be correct, you should replace the cam chain tensioner.

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 ==Cam chain tensioner theory==
-How the tensioner works: The springs push on the push rod, which pushes on the cam chain guide. The ball and retainer assembly, in combination with the push rod and the tapered barrel of the chain tensioner housing, form a ratchet mechanism that allows the plunger to go out but not come back in under normal use.
+The purpose of the tensioner is to take up the slack on the cam chain as it stretches with normal use. So it's designed to only move in one direction. The springs push on the push rod, which pushes on the cam chain guide. The ball and retainer assembly, in combination with the push rod and the tapered barrel of the chain tensioner housing, form a ratchet mechanism that allows the plunger to go out but not come back in under normal use.
 The negative part of all this is that when the tensioner goes, the cam chain can slap around within the engine, tearing off bits of the plastic that are there to help guide it and protect the metal... which then float around in the engine until they get stuck somewhere or do damage. The chain can also jump teeth, in which case the timing is off and the bike runs terribly, or you have that unhappy valve-to-piston contact. So, if you have a (usually consistent) ticking coming from the upper right side of the motor, and you know the valves to be correct, you should replace the cam chain tensioner.