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[Nettshubby]

So you are calling me a liar, eh Tim? The way to get the brake working properly is to get both shoes hitting the drum together, no geometry needed! What I did achieves this, the brake worked much better because when the lever is pulled both shoes contact the drum together with equal pressure.

[Beezabryan]

Hi Netts, there sometimes are two ways of approaching a problem - the scientific and the practical. Either one or the other or both may be the way forward

[Nettshubby]

Just read Hitch`s method of adjusting front shoes, and whadya know, it`s the same as mine except they used the original adjuster rod.

[Tim NZ]

No one called any one a liar? (What is it with some people on this forum?) Little or nothing I say here will probably make you change your mind. Suffice to say you obviously did not pass your O levels in Geometry.
The article on TLS brake adjustment via the link rod was written by some well intended but seriously misinformed on the functionality of the brake, and it has been slavishly copied and repeated by similar people across the internet for years. For any one who is content with having a mediocre front brake, then follow the link rod (mis) adjustment method.
With ANY divergence in the lengths of the side of the levers will rapidly see one brake shoe wear faster than the other, with diminished leverage (applied force) to the other and rapidly compromised servo action across the brake plate.
For any mechanical TLS brake to function at its optimal the levers MUST be set as a true parallelogram. Set one lever to a different pivot point or length and the applied force changes. One shoe wears, one shoe glazes.

But you don’t have to believe me, if there is a technical library near you, pick up a copy of the book: Mechanics of Automobiles, by H E Barnacle (BSc Eng, AMI Mech E)
He was the senior lecturer on Mechanical Engineer at College of Technology Oxford for many years.

[Nettshubby]

Theory, great innit! Yes, that would work, IF, the shoes were absoluteley identical, IF they were absoluteley central to the brake drum, and we all know how absoluteley accurate the machining of Indian components is. Carry on proffessor, I suppose it will be good for sales of vernier calipers while everybody sets up their parallelograms! I'll carry on setting my brakes my and Hitchcocks way that works in the garage, not lab! Oh, I forgot, my bike has a disc front!

[Nettshubby]

BTW Timothy, I said that my method worked on my bike, you wrote it could not, therefore in my book you said I was lying. But don't worry, I won't take it further. 😉

[Scalyback]

My front brake usually squeals like hell for the first turn of the wheel in the morning, so Being a quiet road, I keep the power on and squeeze the front gently until it goes quiet, then it is usually ok for the rest of the trip.



I had Chris the mechanic change them over, but the old shoes look almost unworn. I think there are two slightly different types of shoes, but if you want to compare or try the ones I have, then you are welcome. I was going to send them back to our hosts, but have not done so yet!



Why do my TLS shoes still grab and squeak first thing, and after a few miles sometimes?

[Bertie the Bullet]

Hi Scaly, back in the ol' days when I worked in the motortrade we never got complaints about squeaks and squeals until the UK guv banned asbestos linings, and then all of a sudden, speaks and squeals all over, it took a while for the companies to sort out material that didn't make loads of noise, so guessing it's down to the material the linings are made from...

[Scalyback]

My new shoes sing like a duet for the first couple of revolutions. I have to remember to apply the brake in a controlled fashion when first starting out, otherwise the first proper braking at the junction can be very unnerving!

[Tim NZ]

With new linings any grabbing is usually related to not enough lead chamfer on the forward edge of the linings? Or if you have had the shoes off recently, and your levers are not set as a true parallelogram, you have swapped the shoes around. The one shoe that has worn more than the other and the unbalanced servo action on the brake-plate is applying distorting force across the brake plate. With the SLS shoe front brake this situation can result in instant brake grab and potential locking of the wheel in extreme situations.
Make sure that the plate retaining/locating taper faced nut on the axle is secure and the fork leg abutting hard up against the nut? If that nut is loose (or able to back off) and the brake plate is free to wobble the linings will wear unevenly from side to side and your brake will be pathetic.
Squeal is often from glazed linings, and happens until the linings heat up; noise is loss of efficiency, and glazed linings are totally inefficient. Too much dust inside the hub can also contribute to squeal but would be a rare event with a Bullet wheel
For any one who insists on following the link rod adjustment process, it is critical to NOT reverse break shoes
A test: Loosen off the taper face axle nut, apply the brake, and while holding the brake on, retighten as best you can the axle nut, finger tight is Ok. Now release the brake and check how much slop there is on the brake plate or how much further you can easily tighten the nut.
That disparity is ‘lost motion’ in the brake assembly which has a significant negative effect on performance.
2nd test. With wheel clear of the ground and free to rotate apply the brake.
Does the wheel move ever so slightly? You have problems that can not be solve by continually misadjusting the link rod.