By Patrick Zambori, H-D tech at Wisconsin H-D
Since you cannot get to the ends of your swingarm pivot bolt, the manufacturer in their infinite wisdom placed precision drilled marker
holes in the swingarm, just a few inches forward of the rear axle, tiny little eighth inch holes. You can measure from these holes to
the rear axle center and align the rear axle to them. Best way on the Dyna is to back off both adjuster bolts one turn, loosen the axle
and knock it forward, then snug up the rear axle just enough so that you can't spin the spacer by hand. Measure both sides from the axle center to the marker hole, and draw the smaller side of the two to be equal with the other,
then draw them back one flat each until the belt tension is correct.
Then go for a ride, and pay attention to whether or not the center of your body is in direct line behind the steering neck. If it is not, a bit of fine
tuning may be allowed. If it is -way- off, your swingarm may be twisted.
Rules of alignment.:
1 - the front wheel will always go directly straight down the road
2 - the rear wheel will always follow parallel to the front wheel, although not necessarily directly behind the front wheel.
Changing the angle of the rear wheel in the swingarm not only changes the alignment of the belt, it also changes the position of the
rear wheel relative (in line or not in line) to the front wheel. Many times,
the perfect alignment is a compromise between the two, as frames and swingarms are welded together with some variance from unit to unit.