This may be a silly question, but what would be the advantage of a chain tensioner if a person has a concentric drive? I have seen these at HPD, but was wondering why it would be worth having. I thought that when the design changed from nonconcentric, that they solved the chain snapping problem.

I have seen that back of a transmission when a chain breaks (with a hole big enough to put my fist it) and it wasn't pretty. I don't want the same problem, so can anyone tell me what the deal is on the tensioner for the concentric models.

Also, chain sounds like it is popping at times. Is this an indication on the swing arm being loose or having worn bushings?

Thanks,
SnowDrift

 

To be honest, the concentric drive machines should be called 'almost' concentric drive. They are very close, but not quite truyl concentric, meaning the chain tension will still vary depending upon where in its range of travel the rear swingarm is. The tensioners are probably only needed for those who run their machines ragged. Also, I don't think adjustments are needed as often if you have the tensioner.

What kind of popping sounds? I had an Xpress that was driving me crazy, making an occasional popping sound from what sounded like the chain/sprocket area. It only happened once in a while. Turns out it was a loose hub nut on the end of the axle.

Does it go pop every time the wheels go around? If so, look for a bad rear sprocket, or bad rear bearing. If it happens more often than every revolution of the rear wheels, look to the front sprocket. If it happens irregularly, or less often than each turn of the rear wheels, look for a bad link in the chain, or an axle bearing.

If the swingarm is loose or has bad bushings, you will be able to feel it if you jack up the rear wheels by using a floor jack under the rear part of the frame, letting the rear wheels hang loose. Try to wiggle the wheels, and any looseness should be felt. Wiggle the wheels every which way & look or have a friend look where it wiggles, if it feels loose. If it feels tight, it likely is.

 

Snow Drift,

The chain tensioner would be helpful if you were to jump the machine. When you land and give it gas or give it gas while in the air and then land, there is a shock delivered to the chain. The chain tensioner lets you run a little slack in the chain to absorb the shock when landing with the throttle on. It keeps tension on the chain in place when you are running some slack in it.

Hope this helps!