2003 Dyna Low Rider Rear Brake Caliper Alignment

[03Twinkie]

I put on some Lyndall Gold brake pads front/rear. Other than that all stock Harley. The rear inboard pad is dragging a little, which keeps the brake rotor warm. The pins showed no sign of wear other than superficial. The pistons were cleaned and retracted into the bores. Even with the inboard pistons fully retracted, the inboard pad was tight during assembly. The outboard pad was loose. I can see through some windows on the top of the stock caliper that the inboard pad is moving toward the rotor and then retracting, but it is still dragging. It seems as though the 4 piston non-floating stock caliper isn't properly aligned to the rotor, but there doesn't seem to be a way to align the caliper or rotor, for example with shims, since the caliper and bracket are one unit mounted to the rear axle and the rotor is hard mounted to the rear wheel. This may have been an issue in the past, but I can't recall if I've ever tested it. Maybe the stock Harley pads are thinner than the Lyndalls.

 

[03Twinkie]

This guy found the same problem, but it was the opposite in that the outboard pad was tight at 10:11 in. Said the wrong spacer was put back in the axle. Besides the factory, the only one ever to have the axle out was the dealer to replace the rear tire. I wonder if this is the problem.

 

[dolt]

This guy found the same problem, but it was the opposite in that the outboard pad was tight at 10:11 in. Said the wrong spacer was put back in the axle. Besides the factory, the only one ever to have the axle out was the dealer to replace the rear tire. I wonder if this is the problem.

That very well could be your problem but if that is the problem, the OEM pads should have been dragging as well and if they were, you should see the difference in wear from the old pads. Unfortunately, the only way you will know for sure is to pull the axle and swap spacers.

You can center the rotor in the caliper by adjusting the spacer width or by trimming some off the part of the caliper that the axle passes through but that should not be necessary unless one is adapting a different wheel. With the correct spacers in the correct locations, everything should line up.

 

[03Twinkie]

Thank you for that. The OEM pads may have been dragging in the past, but I never noticed the excess heat. I ended up taking it in today as it needed a new rear tire anyway. The tech indicated that the spacers were in the correct location. He said the pad wasn't dragging on the rotor that much when he had it up in the air and it should break in over time. The only thing he thought was maybe since they're aftermarket pads, they may be thicker than OEM.

That very well could be your problem but if that is the problem, the OEM pads should have been dragging as well and if they were, you should see the difference in wear from the old pads. Unfortunately, the only way you will know for sure is to pull the axle and swap spacers.

You can center the rotor in the caliper by adjusting the spacer width or by trimming some off the part of the caliper that the axle passes through but that should not be necessary unless one is adapting a different wheel. With the correct spacers in the correct locations, everything should line up.

The rear wheel does seem to be biased toward the left/sprocket side and has been this way since new. I have a picture from 17 years ago (with the temp tag) when I bought the bike as well as from just this past weekend. This bias would seem to translate to the inner caliper bias toward the inner pad as well - I have included a movie to show the caliper/rotor alignment. I have opened a case with Harley Davidson with the argument it has been this way since new, the wheel has been off only twice, both times at an HD dealership for tire replacement, the second time at which I wanted them to check the spacers where they indicated they were correct. The best I can track down (from Ronnie's Microfiche) is the sprocket/left side spacer should be #41591-00A (1.88") and the disk/right side spacer should be #43654-00A (.475"), so them being swapped would be very noticeable and further bias the wheel/rotor assembly further left.

 

[dolt]

The video is not opening. The rear wheel on my '02 FLHT was also off center to the left by more than 1" but never presented any caliper/rotor alignment issues. I replaced the OEM rear wheel on my '02 with a 3.5"x18" front wheel from a later model FLHX and modified spacers to center the new 150 tire and wheel and maintain proper rotor/caliper alignment.

 

[03Twinkie]

The video is not opening. The rear wheel on my '02 FLHT was also off center to the left by more than 1" but never presented any caliper/rotor alignment issues. I replaced the OEM rear wheel on my '02 with a 3.5"x18" front wheel from a later model FLHX and modified spacers to center the new 150 tire and wheel and maintain proper rotor/caliper alignment.

Thank you for the quick reply, the video had to be processed by YouTube. It wasn't working initially, but should work now.