Triumphrat

argh · 09-09-2005

About a mile from my house on my way home today, I noticed that when I rolled off the throttle, the bike really slowed down hard. I was on a steep uphill, so I kept going up to a level stop, pulled over, and the rear wheel locked up as soon as I was going slowly. I looked down, and the rotor was glowing orange!

The rear brake was totally stuck. I tried pulling up on the pedal, heard a "pop", and was able to ride the remaining quarter mile to my house with no rear brake, just front.

My commute is mostly highway, with a high speed exit ramp down to a series of about 6 stoplights - I split to the front of each, didn't really notice any issues until the just before the hill. Each time I rolled off, it slowed down harder, but I kinda thought that maybe it was just heavy engine braking because I was close to being out of fuel (light was on, less than a gallon left).

I mostly use my front brake, and just use the rear for settling the chassis when fully stopping and for holding the bike still at lights. I certainly wasn't riding it, and I didn't mash it either.

The pads are out of the calipers and have welded themselves to the rotors. The lines are slightly melted, but not leaking.

Grr. Bike is less than a year old. ***!

I had a new rear tire put on a week ago, but I've had an aggressive sport ride and a week of lanesplitting hijinks since then. I'd have expected any dealer screwups to have shown up pretty quickly.

What could have happened? If the brake had locked up while I was between trucks on the Bay Bridge... eek.

[ This message was edited by: argh on 2005-09-08 23:07 ]

miker · 09-09-2005

argh, bad news mate.

Not sure whether this is the case with your bike, but it's possible.

On later model softails, when the rear pads wear too thin, the actual piston can get jammed in the bore, hence not allowing the brakes to release. Put simply, the piston doesn't run in the bore straight and grabs on it's way bakc after you apply the brake. This is reasonably common in HDs, but only when the pads get really worn and should be replaced any way. The older the caliper gets, the easier it is for the piston to jam. The work around is to make up a kind of a shim to put between the piston and the pad, so as to stop the piston from going out as far. Most of the time this cures the problem.

Of course, if you check and change your pads when needed it shouldn't be an issue. Remember, even when you never use your brake, there is still some wear because the pads sit close to the rotor. I never use my rear, except to hold the bike at lights, but I still have to replace the pads every so often.

Just my $0.02

Mick

PaloAlto · 09-09-2005

Argh,

There was a recent thread where a rider got a stone stuck in the rear brake lever, keeping the brake "on". Similar results with different details. It caused quite a bit of damage to his rear brakes. I hope your cost to repair isn't too bad.

Bern

argh · 09-15-2005

They couldn't figure out any mechanical reason why it failed. The pebble theory sounds possible to me.

The rotor is warped and gouged (no biggie, will replace it) but the rear brake line is weeping a bit where it melted. This is of more concern to me.

Anyone know where I could get a rear brake line quickly? I have a friend out who was supposed to be borrowing the bike.

What would I need to know to buy an aftermarket line? Nobody stocks the part, and it will take too long to order.

Thanks for any ideas...

Hairball · 09-15-2005

I have built stainless lines from parts i got from a hydraulics supply company in Tampa Fl.
They dont have a web site.
but you will need to know the length of tube + banjo hole size 10 or 12 mm + thickness of banjo + angle of banjo.

If you find a supplier in your area, just take the whole line assembly to the supply house to get the proper fittings.

Captain_Rat · 09-15-2005

Try these guys:

http://www.spieglerusa.com/cfm/brakelines.cfm

Capt.

Yoshi · 09-16-2005

dont want to scare monger but have heard of this problem on a rear before.... it was where the brake pad came off the backplate and then the metal backplate was forced by the piston onto the disc. In the piston assembly there is a ring seal keeping the fluid in place and on some designs if this is pushed to far out it wont retract and so stays locked on. Its happened at work on one of our brake simulation machines and it makes a serious mess.