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I'm always one to do the easier thing first so try this first. You can "unstick" a stuck tensioner without even removing it form the bike. This is called the "Grambo Trick":

You just take the little bolt off the top of the tensioner housing. Then turn the little slotted bolt inside. You can feel one way (clockwise) retracts it against the spring. Let go and it will spin back in. The idea is that they sometimes get "stuck", so after it spins back down, try to turn it a bit more in the CCW direction. Dunno if it's the plunger itself that sticks, or the chain guide inside that needs a bit more pressure than the spring allows to "unstick". Anyway, this is a no-risk process and some members have said they've gone thousands of noise-free miles after doing this. grambo
If that doesn't solve the problem then you need to reload the weak spring in the tensioner. Gypsy has great instruction at her website on how to do this. Several of us have used these instructions with great success. You can get those instructions at this link:

http://ourworld.cs.com/moonmist115/tensioners.html

James Larsen has instructions and great pictures at this site:
http://www.tocmanufacturing.com/ACCT_rebuild_Instructions.htm

By using Gypsy's instructions and James' pictures you will find that you will be able to do this fix yourself. If there is anything you don't understand you can post the question to the group and one of us who have done this will be able to help you through it. Good Luck!

Q: When you remove the ACCT (automatic Cam Chain Tensioner) to preload them, is there a need to replace the O rings or are they reusable if they are not damaged? Also to try "Grambo Trick" how far Clockwise is safe ? I tried about 1/4 turn and it did not seem to make any difference, so I think I may have to pull and preload the springs.
A: The only o-ring I remember seeing is the one under the bolt that you take off to do the Grambo trick. I didn't need to replace mine. If you do the Grambo trick with the engine off you can turn the slotted screw clockwise until it stops then let go. It's real temping to want to do it with it running and that is when you need to be aware of what you are doing. If you turn it CCW with it running and the engine smooths out but starts tapping again when you let go, you know then that you need to preload the spring.

Q: Hmmm, I did not try to turn it with the engine running, but with the engine off, I could not turn it CCW at all. Should it turn hard or easy CCW?
A: When you turn it CCW you are actually trying to extend the tensioner plunger. The plunger is already pushing on the cam chain to take out the slack so there shouldn't be any movement. Is there is then there is still slack in the chain. So to answer your question it should be hard to turn it CCW.

A: Have you read my write up on the ACCT in the files? I explained exactly how the tensioner works. It's basically a spring forcing the slotted screw to unscrew out of the plunger which makes the plunger stay extented. What you are turning when you do the Grambo trick is the slotted screw. Turning it CW screws the screw into the plunger which makes the plunger retract. Screwing CCW turns the screw out of the plunger extending the plunger out.

Picture a bolt and a long nut. The bolt is the screw and the nut is the plunger. To get the nut closer to the bolt head you turn the bolt CW. To get the nut away from the bolt head you turn the bolt CCW. So you count the number of turns it takes for the nut to get to the bolt head is what he is talking about. That is the full extension of the tensioner. When he puts the tensioner back in he counts how many times the slotted screw turns. He is at his full extension limit.

Q: I posted a couple days ago about a 91 ,750 and if the milage was tooo high. last night i went to drive the bike. it looks and drives fine, when it is sitting idling, the one side of the engine makes a kinda clacking noise. the guy said it did that when he bought it almost 2 years ago and he hasn't had a minutes problem with it. I used to work on boat motors and some Johnsons would sound like something was gonna comeout of the block at any minute, but they ran fine and ran for a long time. the sound is like something rattling around in the head, i didn't know if maybe this was a common sound or what could it be, any advice, insight would be greatly aprreciated.
A: That sounds like the problem I'm having right now. It's my automatic cam chain tensioner (ACCT). I tried the Grambo trick yesterday to see if it was stuck but this morning I found that it is still doing it. When I get home I'm going to have to reload my spring tension as others have done. If he hasn't fixed it in two years I wouldn't buy the bike. There could be some damage to the valve train.
 
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