Comedy brakes

My TLS has linings from Norton about 15 or 20 years ago, so they are asbestos free.  It snatches dangerously just after I leave the shed if it's been laid up for a week or two, or of it's been wet.  I have to apply it as I ride up the straight road until it clears.

A fortnight ago it did the same after was caught in the rain on my way home.  It either slipped or snatched.  Scariest trip...low speed, driving rain and only the back brake.

Today's task...remove wheel, clean dust, and improve the chamfer on the leading edges.

Does anyone have suggestions?  Would a very much longer chamfer help to reduce snatch, even if there's a bit less effective braking area?  Or even something simple like better return springs?

I have comedy brakes too. They squeal with delight when I apply them.

I'll get me coat........

“Perversely my 99  with unknown autojumble shoes  will stop dead  in reverse but only half hearted in forward motion.”

That usually means the trailing shoe is contacting the drum before the leading shoe.

Have you seen this in the manual?

Hydraulic brakes that 'go to the floor' is air in the system, just needs bleeding!! I have always chamfered the leading edges of drum brakes. Some years ago when I first had the TLS Commando brake and was totaly un-impressed with its rubbish performance (seeing how good the SLS is) I phoned the factory, they advised me that the large central hole was there to allow for centralising the brake plate. But the TLS has adjustment on the brake rod for that!!  So I had a bush made to reduce the hole dia, much better. Then another thing we find is that when adjusting the TLS with the rod, they shoes don't come on together-you can get them on at different times depends which 'spanner' you pull on first/most. All proves the need for a stiffening plate. But there has also been the realisation that the TLS shoes are narrower than the SLS ones!! Seems a backward step.

Regarding adjustment of TLS.  I set my adjuster rod length on the bench.  Adjusted until both shoes started to move at exactly the same instant.  Then mounted it on the bike, giving a good hard pull on the brake lever before tightening the spindle.  MOT inspector was very impressed by its performance.

The book method of using two spanners to hold the shoes on and adjusting the rod to fit doesn't work for me because (unlike the author of the Book) I don't have three hands.

I'm not aware they are narrower, but the last shoes I had professionally lined came back 1/16" narrower due to over enthusiastic trimming by the firm that fitted them.

“ i had an engineer friend open out the brake plate as suggested. It was completely ruined by that”

I attacked mine with a file and nothing was ruined. Seems unlikely that all the 1964-on backplates were ruined either.

Athough the bigger spindle hole did allow centring, removing lining material from the trailing edge of the trailing shoe has made a bigger improvement to the brake.

I’m not recommending you do anything mad like this.

My third hand when adjusting a TLS is a cable tie looped over the lever and throttle grip.

I don’t know if your brakes work or not.

”my 99  with unknown autojumble shoes  will stop dead  in reverse but only half hearted in forward motion.”

“swap shoes like I do , it achieves a similar result by increasing the wear on the trailing shoe and keeping the pressure on the leading shoe which does most work.”

Good luck anyway.

hello,

on the Norton SLS brake, its a pity that the brake shoe securing bolts swivels couldnt be made adjustable eccentric so to be able to centralise the brake shoes.

barry

I have seen that grabbing on first use after a layup described as "Early morning keenness" in drum braked cars.

Due to a thin layer of run on the inside of the drum, which has a relatively high coefficient of friction compared to shiny steel. The rust wears off very quickly.

I once had an MZ ES250/2 (the one which looked like it was wearing a 1950s TV set as a headlight)  which my late brother-in-law had rescued from a skip, they had a reputation for lousy front brakes but by careful setting up, making the shoes fit the drum and ensuring that the rather short internal actuating lever was at 90 degrees to the cable as it bit I got them to work extremely well, this made me wonder...

I fitted my turned front shoes onto a rear brake plate (which had a normal, external lever of generous proportions), made a torque arm which clamped on to the front swinging arm and fitted a modified Lambretta cable, and the brakes were SUPERB, one of the best drum brake set-ups I have used, then, having run out of things to play with on it, I sold it to a bloke from York who wanted to have it in hif front room ( it takes all sorts...).

The point is, there are very few drum brakes which cannot be made to work reasonably well, if in good condition and properly set up, conversely, any good drum brake can be made useless if carelessly  or negligently treated.

... the 7" SLS front brake on my ES2 is fine. Of course it won't stop on a sixpence but I think it would match the 30ft from 30mph that used to be the standard. I've had both brakes relined by Villiers Services with their high friction woven linings, as I have other bikes and all have worked well after careful setting up. Of course these linings would not stand up to repeated heavy use, but that's not what I need.

One point on my front brake is that I have a handlebar lever with 7/8" pivot-to-cable distance which of course gives more leverage than the commonly fitted 1.1/16" type.

Some years ago I rebuilt an Ariel Arrow and these were renowned for having bad brakes. However, again, Villiers Services linings, a 7/8" lever and careful attention to bushes etc resulted in a perfectly acceptable unit.

My TLS shoes are 1 1/4" wide.  I'm sure that's no different from SLS.