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Old 01-23-2010, 08:41 PM
Creative Engineering Creative Engineering is offline
Join Date: Sep 2008
Location: Clearwater, FL
Posts: 1,668
Default Re: Im confused about all the chain tensioner problems

I enjoy the chain tensioner discussions also...mostly because the root cause of the problem has nothing to do with the tensioner itself. For some reason, the "why" seems to have been lost.

If you have a bike that has a frame with 3/4" or greater slots in the drop-outs, and the chain clears the frame...don't bother with the isn't needed.

For those who haven't owned motorcycles, believe it or not, even the smallest do not use chain tensioners.

90% of the, coaster brake, beach cruisers have a frame set-up that makes the tensioner null and void.

Now back to the problem:

Let's assume that you have a Schwinn Jaguar. This is a multi-speed bike with a deraileur. By design the frame need only have enough depth of slot in the drop-outs to mount the wheel. There are a lot of bikes with frame designs that are similar, in regards to rear wheel mounting. This frame design offers virtually zero wheel adjustment along the length of the frame. The slots are actually slanted to about 20 degrees off horizontal. A chain tensioner is needed for this type of frame!

Why does the chain tensioner plow into the spokes? It doesn' inadvertently made it happen!

It's simple; the rear sprocket isn't running true, or the tensioner isn't tight.

For all of the new guys out there, and those still having problems with the tensioner...there is a real easy fix!

When you are done with your build, have someone hold the clutch in...lean the bike over on the kickstand so that the rear wheel is off the ground...spin the rear wheel by hand to see if the chain gets tight and then goes slack!!! If it does; don't ride it until you have adjusted the rear sprocket so that it runs concentric to the wheel!!! This isn't rocket science guys. If the chain gets tight, the tensioner is going to move...move in the direction of the spokes! The engine mounts will be stressed to the point of the never ending threads regarding broken motor mounts. Ensuring that the rear sprocket is running true, is the #1 build concern.

In a proper installation the tensioner should only serve to keep the chain off of the frame buy redirecting the chain at an angle that will not allow chafing.

The only time that the chain tensioner actually has to when starting the engine. This is a minor load, and there is no reason why the chain tensioner would ever plow into the spokes if it were securely mounted.

The problems with chain tensioners are related to improperly installed "rag joints"...nothing else.

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