Seems to me if you align the rear axle to the swing arm pivot then the belt should be aligned automatically.  Wouldn't be if the swing arm pivot is out of alignment with the forward pulley but that would be a rarity I imagine.

HighME32 wrote on 11/17/14 at 17:39:41:


Not any better than the index marks.

The most accurate method is to take a stick and mark the distance from the swing axle pivot point to the axle on the left side - then move the right side to match as it does not affect the belt tension much when moved alone.

The belt may not center itself when you align the axle this way, as the bearing in the pulley hub can get loose and allow the pulley to angle forward under the belt tension....which causes the belt to move to the outside edge.

I just use a tape measure. If you measure from the same point on both sides (like the swing arm pivot) then you can get it pretty even.