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[Scalyback]

Tim NZ,



Have you done this to a TLS brake, and if so did it work?



Poor guy wrote all that and got slagged off, but, has anybody tried it?

IF the weather perks up here, I might have a go, see if it works or not, but first, my main (iron bullet) light switch has gone dodgy, causing the lights to flicker or cut in and out. Not amusing on country road with no street lighting, so need to sort that first. It's the contacts I think as even does it on park position.

[Leon Novello]

Hi Tim: Do you have any suggestions about the angle of the rear brake actuating lever. I have moved the lever one notch forward on the shaft spline to try to get more leverage. Although it gives less adjustment on the brake rod, it seems to have improved braking slightly, but maybe it`s all in my mind.

[Tim NZ]

I have been tuning mechanical TLS front brakes for over 40 years; the improvement in braking efficiency once the levers are set as a true parallelogram and the linings have fully bedded in is significant, and will last the life of the linings.
On the track, the ability to out brake ones competitors is where the results really shines.
The rear brake: it has an adjustable fulcrum point that needs to be set at least once a year. PITA job unless you fit lock nuts (NOT NYLOKs) have a pair of super thin spanners and permit the cam housing to just float. The Old 6" SLS front brake, and the double side SLS 6" front brake had what was in effect a fully floating cam assembly, good brakes, but the down side is one shoe wears faster than the other, and then need to be reversed occasionally to even out the wear. The later fixed-center 6+7" SLS brakes were a step backwards; semi or fully floating shoe arrangement is much superior.

Rear brake lever angle as installed at factory is optimal for leverage on the cam, if you re-position the brake arm to rod to open the angle up from 45 degs to closer to 90 degs, (between the brake rod and arm), then you are effectively shortening the effective lever length and shifting the fulcrum point at the cam itself.
The right foot brake lever is a Crock of Excrement: torsional flex in the cross shaft and sloppy pivot points all significantly reduce performance.

[Adrian]

Tim, has anyone converted the RE drum brakes to hydraulic operation? It has been done with BSA TLS brakes. The most orginal RE drum conversion I am aware of is the conversion of a double-sided 6" front drum to 4LS buy a clever Frenchman. Regards, A.

[Leon Novello]

Thanks Tim, I`ll put the lever back to the factory setting. I have other problems at present, went to get a part for the McCullough line trimmer, the dealer doesn`t keep any, came home, got it working, then it started to rain. SIGH!

[Beezabryan]

To achieve maximum leverage should not any brake arm be set with the brake full on and the arm set to be at 90 degrees to the rod/ cable pull, or as close as can be done with splines.

[Tim NZ]

Optimal lever angle is approaching 90 degrees to the cam. With the rear brake the backing plate is offset 45 degrees in relation to the axle/swingarm/foot brake pedal, so if the rod/arm lever is reset so that it is approaching 90deg, then the Arm to Cam angle is increased to 135 degs: over centered, and leverage is lost.

[Beezabryan]

But surely that reduces the effective length of the lever thereby increasing the effort required to produce a level of retardation

[Paulk]

Bryan, My understanding matches yours. I've always been lead to believe that you should aim for a right angle between the rod/cable and the brake arm at the brake plate. This is then turned into a rotating force on the spindle and cam and the actual orientation of the cam to spindle is irrelevant since it is now a rotating force. Now I'm no mechanical engineer but if someone can explain why I'm wrong in plain English I'd love to read it. Thanks. Paul.

[Nettshubby]

Now you've gone and done it!🙀