Re: Disk Brakes vs. V Brakes??

In Message-ID:<8b4oi2hpg4v758oddn9c8mfkb2rs9hujpi@[EMAIL PROTECTED]
> posted on
Tue, 10 Oct 2006 16:45:44 CST, (PeteCresswell) wrote: Begin  

>Per treynolds@[EMAIL PROTECTED]
>>A tandem drag brake and a downhill ATB are not the exact same situation
>>but both can expect to sometimes apply the brake for 20-30 minutes on a
>>very long downhill.  Does this ever occur on an ATB?
>
>I've had my front brake (Hope C2) lock up in that manner when descending
a very
>steep hill.
>
>Somebody who knows can chime in, but my suspicion is that phenom is
limited to
>closed-system hydraulic brakes.  
>
>I also think it's aggravated by having fluid that needs changing bc after
I bled
>the brake, it stopped happening.

That might suggest bubbles 
that expanded with prolonged application heating 
causing the lockup
and would no longer be an issue after bleeding them out

You might think that those bubbles would tent to migrate upward toward
the hand lever and away from the source of heat however, unless there's
a slight leak at the connection to the hydraulic applicator and the
bubbles were forming there as you rode then subsequently heating before
their chance to float away.

-- 

Bart

--
rec.bicycles.off-road is moderated by volunteers.  To find help solving
posting problems, or contact the moderators, please see http://rbor.org/
Please read the charter before posting: http://rbor.org/rbor_charter.txt