I知 Attempting to tighten the chain on my son scrambler 400 4x4 and I followed the procedure to the tee. But as I tighten the locking bolts I can watch the chain sag and become loose again??? Any ideas on what I知 doing wrong

THANKS

Sam

 

Not sure of the particulars of a scrambler but I know I always
-compressed the rear suspension with a ratchet strap,
-adjust the chain to the tightness desired,
-tghten the swivel bolt.
-tighten the pivot point bolt
-release strap

why the chain is moving while tightening?...hhhmmm...how old is the chain and sprockets? an old chain that could have stretched will really give ya fits when trying to tighten it as parts stretch and other parts don't.

 

First does the chain have any side to side play,is it an older chain? can have trouble adjusting if it is.Whats really happening as you tighten the rear axle housing, it has a habit of twisting forward slightly which ends up loosening the chain. You can always tighten just a little more than needed, then tighten bolts on housing. should end up with where you intended. I always adjusted to where chain had about 1/2-3/4" slack at middle of chain at top of swing arm. I Didn't go by how the old manuals still said to collapse rear end and adjust,chain would end up being way too loose!(engineers agreed with me on this matter,this was used before the swing arms were re designed to lessen stress on chain,the front sprocket and swing arm pivot bolt are in line with each other which causes less chain flex from swing arm) Also jack up machine and turn rear tires and see if you have any hi or low spots in chain. If so maybe time to replace. OPT

 

what year? shaft to the front?

 

1998, yes shaft drive to the front.

THANKS

SAM

 

I dont do it by the book either, they were all too loose, on the rear I use a large pair of channel locks and tighten till chain is :snug maybe 1/2 inch of slack, then tighten bolts, as stated you may need a new chain and sprockets

 

with a good quality chain on con-centric drive model, adjustment is very rare. compared to the old ones.
I have had much better luck running something like a Rk x-ring chain with oversize pins, than the bottom of the barrel DID o-ring chain my dealer sells. DID makes better ones as well.