What would cause the final drive belt to get tighter? Chains always get lose after a while. I can understand why. My belt is way tight and I can't figure that out. Ain't had the wheel off, the axle nut is tight and so is the sproket. It was fine about 1500 miles ago (last time I checked it). What happened? Oh, lowered 92' Dyna.

 

When you lower the bike the belt will get tighter. The swing arm does not pivot from the same point as the belt so as the swing arm pivots the belt tention will change.

 

Been lowered for many a year. Belt has always stayed in adjustment. This tight belt be a new thing.

 

My opinion: It didn't shrink. Something shifted. Have you checked it at different spots on the belt? Also, are the springs sagging from the last time you adjusted it? Or not sagging as much? Loaded/not loaded as much? Just adjust it per the book for today and keep an eye on it.

Too tight is generally considered A Bad Thing.

 

Comming from dirtbikes i would suspect swing arm bushings if the shocks are ruled out. I dont know if that applys here though since i know little about yoru specific bike. With weight on a worn out bushing the swing arm will measure longer.

 

The swingarm is mounted on cleve blocks, which could indeed be failing, as they are a sort of rubber compound. In the same area, the swingarm is mounted off the rear of the transmission and that is supported in the frame by rubber mounts, which might also be old and worn. So there are two candidates for things to go wrong.

 

Too tight is generally considered A Bad Thing.

Yep, this is why I am asking. I did not consider the swing arm bushings. Shocks are good, no weight change. I got about 50k on this machine so I guess I will be looking at the bushings (after I do what Hess suggests). If the sucker tightens back up I am checking them. Thanks all!

 

I don't know how many miles you have on the bike, possibly the belt is worn and climbing on the pulleys? Or vice versa. Just a thought.

 

Or the tooth count is off. Any movement in your primary tension?

 

From left field: Have you lost weight lately?