Hitchcocks Forum

Hi all, merry Christmas.. Please can you all help, I have adjusted Bertie's front brake so it just does not rub but it doesn't seem to matter what I do, there is too much travel on the lever and the brake is very poor, could I need new shoes, they appear to have a fair amount of meat on them but the wheel does not seem to run very true and one of the shoes is rubbing at one point on the drum.

Find someone who can fit oversized (too thick) linings to your brake shoes and machine them so they actually fit Berties drum properly. Someone like Henry Price can also skim the face of the brake drum true if it has worn/distorted oval and re-true the wheel itself. A new set of wheel bearings probably wouldn't go amiss. Depending on where you are other specialists are available! A.

Have you checked the cable is a good solid one some I've seen have the property's of used knicker elastic. If its Ok follow advice in technical notes on left for front brake overhaul if you haven't already I done mine with the heavy duty cable & shoes from Hitchcocks and now its as good as any other bike I've ridden.. http://hitchcocks.sincordia.co.uk/pictu ... erhaul.pdf

Have you centred the brake shoes? (Or put the shoes on the wrong way around?) Lubricated the swivel pins? Tightened the adjusters hard and then backed off until the wheel just spins? Checked the wheel bearings?

I agree with Paul M H. My TLS front brake was lethal from new (2000 Bullet 500), and caused me to have quite a few close shaves with modern cars capable of stopping a lot better than my bike. I didn't want to spoil to 1960s look of my bike so I decided to do what I could to improve the standard brake. I bought our hosts British shoes, and a heavy duty cable, and took a long time in carefully setting up and balancing the brake. Having said all that I was rather disappointed with the initial result which didn't seem to be much better than before. However, after a lengthy 'bedding in' period it's evolved into a very good brake indeed. Of course it will never be the same as a modern two-finger operated disc but given a good fist full of effort and the self servo effect of the twin leading shoes I now have a brake the doesn't give me heart attacks and can even make the tyre squeal. Result!

Bertie your post seems to indicate a poorly adjusted pair of shoes, one is biting long before the other which will stretch the cable and be a real bad stopper.
The Bullet TLS brake is not the easiest to get right so I would encourage you to follow Paul M H s advice & see Hitchcocks Tech Note on TLS Brakes

On my earlier Superstar bullet, to improve friction and, mainly, to improve adjustment I did the following; I replaced the adjuster rod with a new one made from a length of M6 stainless screwed rod. This was fixed at the end of the longer operating lever with nuts either side of the trunnion. Next, the threaded hole in the trunnion of the short lever was drilled out to clear the M6 rod, and a nut, I think I used a nylock one, screwed onto it on the outside. To adjust, the long lever was applied to bring the shoe in contact with the drum and held there. (It hepls to have two people here) The other lever is now pulled to put the other shoe against the drum, and the slack taken up by the nut on the rod. You could use a normal nut to take up slack, then a locknut or a nylock nut to lock it. This way each shoe is adjusted indipendently instead of moving both together with the left and right threaded adjuster. With a pair of Hitch's english lined shoes, my brake was good enough to lock the wheel, if one so desired! It was also as good as the disc on my Sixty5 !

Thanks all, I'm going to follow Hitchcocks Tech Note on TLS Brakes as it used to work ok, let you know...

Any one who sat O levels in geometry will be able to verify the following:
The front brake is a mechanical parallelogram, as such any deviation for a true parallelogram by shortening or lengthening the 'adjustable' link rod will rapidly see a reduction in efficiency and the brake become useless due to diminished leverage in either side of the square!
About the worst possible way to set a mechanical TLS brake is the method advocated by the hosts of this forum! Drilling out and reversing fitting and misadjusting the link rod to achieve 'easy' adjustment is the fastest and easiest way to achieve an absolutely useless front brake.
If you wish for ANY mechanical TLS brake to work at optimal efficiency the distance between centers of the two trunnions MUST be exactly the same as that of the brake cams!!
(A nominal 143.5mm, but as with a few too many parts of REI origin that distances is none to vary, hence the 'nominal')
The greater the divergence in the lengths of the sides of the parallelogram, the worst the brake!
The correct adjustment process is a demanding and exacting task that requires the same degree of precision as that of rebuilding a crankshaft!
To achieve an efficient TLS front brake the first step is to accurately measure and confirm the centers of the cams, that distance MUST then be set on the link rod trunnions and all further fettling is to eliminate 'lost motion' and optimise effective leverage.
Once correctly set, the Indian TLS front brake is able to do 'stoppies'!

Tim

Having taken ages to write a very big an informative reply only to have my computer scrap it, I'm not writing it again so heres the quick version.

The shoes were not centred, they are quite worn , the cable has stretched.

Have centred them and re-adjusted the rod and cable the brake now works a treat.

There is no adjustment left so will be replacing the shoes and cable very soon.

Mr H's notes work, i know, i followed then yesterday.