Open Belt Drive Adjustment
 

Is there any way to adjust the belt on a bdl open belt drive? Does anyone know how much play in that belt is too much play?

No. Provided the motor plate slides on properly everything should be fine. As far as tight goes how tight is it? You should just barely be able to get the belt on while putting the clutch basket and motor pulley on at the same time. Now you must be sure it is tracking straight. Also they tend to be looser than most people think.

Of course if he belt is too big that would be an obvious problem.

Well the belt is the correct one, bt it may just be old and whooped out. there is about an inch of play, 1/2 p and 1/2 down in the belt and it seems to be more than normal. Is there a way to adjust tension or is a new belt my only route?

Did you pick up an old used drive? I would call BDL and see if they have a spec for it www.beltdrives.com If the belt is suspect then it may be time to replace. They last a long time and I have never heard of one stretching but it is possible.

With that being said my internal drive is about that much play.

Makes me nervous it may be something more serious than the belt that is warn out. Thanks for the intel guys.

Assuming for a minute that your asking about a Twin Cam engine setup.
Even trying to put slots in the back plate to allow for adjustment would be a waste of time and effort.

The newer Twin cam engines, unlike EVO's or Shovels have the trans case bolted directly to the engine crankcase.
So the distance and alignment between the crankshaft and the trans input shaft is permanently fixed by the cases themselves.

So unless the pulleys have a significant amount of wear on them the belt is probably normal.
Just like the drive belt or a car's cam timing belt they are deliberately designed NOT to stretch.
The only way you can stretch one is to break the cords inside it and once that happens they break long before they get a chance to stretch.




BTW from one ex-herd member to another. :icon_patriot:

Well upon further inspection the engine side pulley has some play too it, which I'm assuming is not good, and may account for some of the play in the belt.

Always great to meet a fellow paratroop and especialy one from the herd. Thanks man.

Just curious did you buy this set up used? Good thing is you can replace the insert for the motor pulley through BDL.

It's on a bike I'm doing a tranny on for a friend. The more I start to remove the more issues I confront. Hopefully it is just that spacer behind the pulley. it's a 3" belt so it's huge. Have to imagine that has to weigh on the pulley over time.