Some years ago I rebuild my front wheel and had the brake linings re-newed bij a professional car workshop.
Ever since the frontbrake is sort of "overreacting" a bit, like it is blocking - or trying to, making an awfull noise.
The question is, what can be done about it ?

And could it be that my spokes are to tight ? I've heard people say that it may effect the shape of the brake drum (could end up a little un-round....?)

Has anyone ever experienced this before ?

A distorted drum would give an on/off affect when you pull the brake on.
If you are getting a loud howling/squeak & vibrations it could be a contaminated drum ... grease or oil on the lining, or linings that have no chamfers on the trailing edge. often relining companies don't put a chamfer on for you like alot used to.
it's important that the drums are completely cleaned on assembly (I use thinners) as anything there will impregnate the liner & cause ongoing problems.

nasty old me thought this was a wind up at first, how I would like an
"overactive" front brake on my G3L, but most of my spokes are loose anyway.

several things come to mind here, first you need to chamfer the leading edge of the linings, this is the bit of the lining that the drum hits first as it rotates; and not some poofy little bit off the edge but about an inch back at 45 degrees or more.

another old dodge is to put a diagonal hacksaw cut part way across the lining just behind this cut to collect dust.About 1/16th inch deep is enough.

But probably your problem is down these new non asbestos brake linings that the eussr has forced us to use; they are definately not as good as the old stuff, and I think worse when wet. wet make them grab. Do you jet wash your bike? if you do stop now.

I, being a nasty right wing cynic buy up nos brake linings whenever I come across them. I reline my own shoes.

below is the best pic I can find to illustrate the above advice

I really ought to make a new years resolution to be kinder to younger owners of older bikes.

Thanks for the photo, another one added to my growing library showing me how I should do things.

email (option): tmuir12@gmail.com

I also forgot to mention that a friend servicing a front BSA brake a couple of years ago after the owner had complained of "unusual feel" found the drum to be completely full of grease. The owner explained he had greased the hub once a week with several pumps :D

I have had a problem on more than one M20 where the brake 'locks up' very violently when first applied...If the brake is released it then works OK after that.

The 'lock up' was so violent on one occasion that the force induced pulled out the rivet that goes through the 'rim' of the brake plate to secure the brake torque arm, and bent the torque arm itself completely out of shape...

I admit I haven't yet been able to identify the cause precisely...

However, I now attend to a number of aspects of the assembly during overhaul as a precautionary measure...

1) I run a weld along the back of the torque arm and weld it to the rim of the brakeplate, to provide additional support for the rivet.

2) I ensure there is no more than minimal play between the brake shoe cam spindle and its housing in the brake plate.

3) With the wheel bolted up tight into the forks but without the torque arm bolt fitted, I ensure that the torque arm is just touching the block in the fork leg that the torque arm bolt passes through...
This is to be sure that when the torque arm bolt is tightened it is not pulling the plate out of alignment with the hub/drum.

4)Ensure that the shoulder on the torque arm bolt is in good condition and is a good fit (across the slot) in the brakeplate 'keyhole slot'.

5)Check that the shoulder on the bolt is shallower than the thickness of the torque arm material. This way, when the bolt is tightened it is sure to clamp the torque arm firmly to the back of the fork leg..
Take care also when tightening the torque arm bolt locknut that it doesn't undo the bolt as it is fully tightened....

Finally ensure the leading edge of the shoes are chamfered as describe in a previous post....Ian

email (option): ian@wright52.plus.com

I should add that that photo actually alludes to a further brake mod to the shortening of the TRAILING edges which improves braking no end.
Its from the AMCOC site.


As for greasing hub bearings at any time after intial assembly thats a really good way to bugger any brake.

Ian, the twin leading front brake on my Commando used to grab violently. It seemed to be when it was first used and would lock up the wheel for a moment. Very unnerving and dangerous. I didn't really know why it did it but seemed to be caused my moisture. It did it once during a heavy rain storm in Cornwall and I had been riding for a long time, I lightly touched the brake and it locked up and the bike started to go down. A quick stamp of the foot saved me and the brake released. New brake shoes didn't cure it so I had the drum skimmed. I've got a very slight kangarooing now when the front brake's on although it looks ok with a pointer on the inside of the drum when spun. It's getting better with more use but at leased it doesn't grab now.

email (option): horror@blueyonder.co.uk

Hi Horror...Dampness may well be a factor..It happened to me a couple of times the first time I braked after leaving home in the morning...If that were the case a change of lining material may be the answer as well as the other points mentioned...

The 'green' linings used in the Ariel hubs fitted to late 50's BSAs was a bugger for it as well. That lining material was never used in the M20 though to my knowledge...

Regarding modern materials you don't really know what you're getting...particularly if the work is carried out by a place that does cars...Ian

email (option): ian@wright52.plus.com

I have a stock of ferodo pink linings as used on AMC bike sinthe 50's.

we used to use those when I prepared ISDT Triumphs in the late 1960s as it works well in the wet.

I stick with the old stuff I know, sometime sits better to be a regressive old sod

those sort of instructions were written years before by some one who was more regressive than I am.

I only ever grease wheel bearings on assembly,then I leave them alone until they come to bits again for any reason.

overuse of a grease gun is for the ill informed. I have often resorted to melting grease liberally applied to head races out of the frame tubes with the use of a blow lamp.Likewise its good way to make girder fork friction discs useless, however plenty of grease in fork links will ooze out and flop onto your knees when riding which at leaast makes them waterproof

I used to (liberally) apply grease on assembly only.
However, I found that riding my M20 off road lead to fairly rapid failure of the bearings as water was getting in..particularly into the rear bearings..

These days I pack the hubs on assembly as per the instructions, give them an occasional stroke of the grease gun and remove, repack and readjust them every 12 months as part of my major Winter service...

I guess it's down to a degree to what you do with the bike...Ian

email (option): ian@wright52.plus.com

and after off roading you jet wash the bike?

No..I don't have one of those....Ian

email (option): ian@wright52.plus.com