Rear brake keeps dragging

[tallbill17]

I got a 87 FLHTC and the rear caliper keeps sticking. It starts dragging after about 7 miles of driving. The first thing I did was clean the caliper, that didnt work, the next thing I did was rebuild the caliper, that didnt work. Im stumped!! Anyone have any ideas why this is happening?

[pacemakertom]

I can't help with why it's sticking, but I do have a new caliper for sale and upgrade to the new brembo caliper.
Tom

[hardheaded]

try taking master cycl. apart and cleaning it.it has a relief port in it .first take cover off and use small wire or a pin and make sure the little holes in bottom are clean,if you get it working then run a bunch of new fluid though system.next move rebuild

[juiced03]

Replace rear brake hose and rebuild or replace the master cylinder.

[bagga]

did you change the caliper piston when you rebuilt? i rebuilt my rear caliper on my 85 a couple of years ago because the pistons had some very small burs on them. the burs make the piston bind on the big o-ring in there so they won't retract.

[tallbill17]

Yup I replaced the piston..

[Rollmeaway]

If you are satisfied that your rebuild on the caliper is satisfactory I would go directly to the hose. I have seen them collapse inside & when the brake is applied it will restrict the hydraulic pressure from coming away from the caliper causing it to drag Like Juice has suggested.

The age of the hose alone would be of concern to me.

[hardheaded]

i would think your piston in the master cyl. is not returning all the way or your relief port is clogged,but have seen that brake hose collapse just like rollmeway has stated.