[dewjantim]

During periods of wet weather, the first time I apply my rear brake it makes a terrible vibrating noise, like a loud sqawk. Won't stop the bike when it does it either. Anybody else have this problem.......Dew.

[Spitting Bull]

Dew, I don't go out on the bike in wet weather, but I get a similar sound the first time I apply the rear brake when the weather has been damp.  Or the morning after I have washed the bike, dried it and put it away.  I put it down to a fine coating of rust having formed on the inside of the drum.  There is also an effect on the front brake, which is also a drum brake on my bike.  The first time I apply the front brake under these circumstances - usually at the bottom of my drive when the bike is moving very slowly - the front brake is really fierce and often locks up.  This only happens the first time I apply the brakes.

Tom

[Foggy_Auggie]

I've had the same effect only on my rear brake.  My own trouble shooting indicated a rear brake adjusted too tight where there was slight brake shoe friction with the drum while operating the bike - heat related.

If the rear wheel just spins freely on the centerstand (with the chain lube warmed up) without any brake shoe friction, my rear brake behaves normally.

The wheel hubs are aluminum alloy, so oxidation from moisture is not much a factor.  And this only happened on my brake when applied below about 5 MPH.

I think it's a brake shoe material issue. When some glazing occurs with usage along with heat and moisture.

Regards, Foggy

[mbevo1]

I'm fairly sure the front and rear drums have a steel liner in them... I had similar problems with my front drum when I washed it and then let it sit for a week without taking it out and dragging the brakes lightly for 15 seconds or so to dry it out.  VERY loud and VERY VERY grabby... had to remove and steel wool the drum to get the rusty-looking patches off.  Big PITA...

After that, I've made sure the breaks where dry when riding in the wet or after a wash, and haven't had any howling/grabbing...

Mike and Stumpy in Michigan

[Foggy_Auggie]

Thanks for the heads up on the steel liners!

One these days I'll  have to remove a wheel to mount a new tire - probably a couple of years away.  Ditto for brake shoe wear.

Regards, Foggy

[krodaddy]

My front brake is a little grabby on a cold damp morning, smooths out after a couple of slow speed stops while getting out of the neighborhood. The rear drum brakes on my 93 dodge caravan do the same thing.

[Kevin Mahoney]

The rear brake drum is made of cast iron. One issue with all drum brakes is their behavior when wet. When wet they lose a lot of effectiveness as you have pointed out. Back in the day, the standard procedure was to operate the brake a bit when wet to dry them out (does not take long), this is also a good practice after going through a good puddle.

[dewjantim]

Thanks for all the input.....Dew.

[dogbone]

Dew ( Is that short for Dewers scotch?) My 99 bullet does it too, just one time. I thought it was brake dust. It actually locks up on my gravel driveway.

[tex]

hey bulleteers,
I,too,would have trouble periodically with the rear brake squalling and grinding. Mine would
act up whether it was wet or dry. I tried several remedies; turning the drum, new shoes, wheel alignment, breaking the glaze on the shoes and drum, etc. I even went as far as
having a machine shop make a brake cam bushing for the backing plate with less play in it.
Everything seemed to help, but the problem would keep returning. It would even crack the
ears on the end of the shoes where they ride on the pivot pin. I finally put a micrometer
and right angle square on the backing plate and brake anchor pin and found out that the
pin was not perpendicular to the backing plate. Therefore the anchor pin and actuation cam
were not parallel, and the shoes were riding cockeyed. They would work sometimes and
then they would squawk, squeal and grab. A new backing plate and anchor pin seemed
to solve the problem. Never had the squalling or grabbing problem with the front brakes
like the rear, but they would tend to be grabby when wet.
Tex

[exiledcarper]

I used to ride an MZ 250, a company bike, about 30 years ago while working as a courier.  They had a particularly nasty front drum brake.  It was pretty ineffective in dry weather, I once got a 6 month driving ban for "brakes not adjusted correctly", when in fact they were as good as you gcould get them on an MZ.  When I got pulle dover, the cop told me to apply the front brake , while he tried to pull the bike forwards.  Bingo!  Despite me grabbing the lever as hard as I could, which was in perfectt adjustment, he was able to turn the front wheel with little effort.  Bye bye license for 6 months .  Can it get much worse , I hear you ask?  Indeed it can, the same front brake would not work at all in the wt, no matter how hard you pulled!  I say it wouldn't work, not quite true.  You would despeartely heave on the lever for several seconds, with ZERO braking, until the brake would emit a high pitched squeel.  At this point you had better let go of the lever, as the front wheel was about to lock !!!!  So that was it, from NOTHING to LOCK UP, with nothing in between.  Of course the brakes perfectly matched the Eastern European Pneumant tyres, which would regularly slide out from under you while attempting VERY MODERATE cornering in the DRY!!!  We all had so many spills (you can imagine what they were like in the wet), that all the company riders went on strike one morning until the boss sent us off to get some British rubber.  It was under great protes, as he was rather careful with his money to say the least.  I hope you're reading this Schister Temple!  His issue was that the tyres were showing no visible signs of wear after 8 or 10 THOUSAND miles!!!  No wonder we used to callthem the Wooden Tyres .  Yes, the MZ was about as retro as it gets, in that nasty Eastern Bloc kind of way and potentially deadly on the choc full , rain soaked streets of Britain.  They were cheap though .  To be fair , they were pretty reliable bikes and the later models did get an excellent Brembo front disc.  I do sometimes wonder how many riders didn't survive the old "Supa 5" models though .  So yes, drum brakes can have there foibles, but hopefully those on the lovely Enfield are much better than those dreadful MZ's.

[RagMan]

Wow, I got given one of those things.. First thing I did was graft the front brake from a BSA Bantam onto it.. It worked fine after that. The guy that gave me it said the front brake didn't work, so I never tried it. Threw it into the back of the transit I had at the time, and changed the brake that evening. The bike, after the BSA donation, was a great little thing. Smoked a lot, but went fine.

[exiledcarper]

here's the mz in all her glorious ugliness. 

Old joke......RRRRingg, dingggg , dinggggg!!!!   "there goes an MZ".........................................
..."there goes the exhuast pipe!"

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[RagMan]

Ain't they just plum ugly.. I love 'em.