Auto Primary Chain Tensioner
Previous | Home | NextThe last thing that I want to show here is the automatic primary chain tensioner. I'm trying it out; not because the primary chain needs constant tensioning, but instead because it seems that '07 and '08 motors are mechanically quieter.
The chain tensioner looks to be a very well-designed device. It allows total freeplay of the primary chain as it wears. If the freeplay becomes excessive, the tensioner moves to the left one ratchet tooth. At that point, a pair of hidden springs keep light spring tension on the chain and restrict it's freeplay to about 1/2". As the chain stretches, total freeplay is once again developed until it becomes excessive. The ratchet can then move another tooth. It cannot tighten if there is any pressure at all on the primary chain. Hundreds of thousands of '07 and '08 TC-88's have this tensioner mechanism. And sure enough, it IS quieter. I like the absence of the primary chain noise.
In this picture, the tensioner is
still being held in place by the shipping tab (closest to the clutch
pack). The tensioner mechanism was bolted into place, adjusted for
significant top-strand free-play. Then, the shipping tab was
removed and the mechanism moved to the left about 3 teeth. The two
7/16" bolts were then tightened per the instructions and the primary
case installed. It was that easy.
