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[Tim NZ]

Nice workmanship, but very poor design! Not least that the former water drain out of the bottom of the brake plate is now acting as a Oil and Water scoop directing it into the hub!


You have changed the trailing/leading shoe positions reversed the applied leverage point, AND kept the old lever?


Whilst I can understand your wish for a better rear brake, your efforts would have been better spent simply fettling both brake shoes (Pivots and faces) so that they both sat True and Square to the cam and drum.


The stock std rear brake is perfectly capable of locking the wheel when it is correctly set-up...

[Count Johnny]

Hi Tim



Thanks for your kind words.



Happily - having ridden Slo Poke, in all weathers, with his brakes in this orientation, for over 15 years - I can report that the former water drain does an equally poor job of scooping oil and water, and that the fundamental design has worked very well.



Also, elsewhere in this thread, I did refer to the fact that the drums and shoes had been fettled, by Classic Brake Services, and were very good - perhaps too good.



Indeed, the point of this thread was not ask how I could improve my brakes, but to ask how I might get the brake lever to live with it all.



Thanks for your advice, though.

[Bullet Whisperer]

I can testify to the power and positive action of that brake! As already mentioned above, after locking up on me, I pointed out that the 12 o'clock position for the brake anchor stud was not ideal, especially as it was put through a slot in the frame running fore and aft, above the wheel spindle slot. The brake plate slewed anticlockwise very slightly when I applied the brake, pulling the brake on even more and locked it up. Both Count Johnny and myself realised what was happening and steps were taken to improve matters - and judging by the last photo, more has been done since. Regarding the original question, the main drawback with the Enfield brake arm is that it relies on a close fit on the operating cam's splines and a nut to keep it on the spindle, wound on from the end of the spindle, rather than clamping tightly onto the splines, as seen on many other machines. That said, I reckon genuine Redditch components would probably be more robust than the Indian components probably fitted to this machine. Cheers, Paul.

[Bullet Whisperer]

The extra work I see has been done which I refer to above is actually seen in the second picture, sorry!

[p]

I doubt the splines would be long enough to get an extra thickness from part of a spare lever - which could pick up on longer rivets - if the cam boss was reduced, but would there be room to grind a short square section twixt spline and cam in order to insert a plate to reinforce similarly I wonder, again you would need to reduce the boss to give room.

Also, maybe some calculated heating and quenching to harden splines, perhaps to the degree one used to do for screwdriver blades? I seem to remember "light straw" was the term for the appropriate heat colour before quenching....

[Tim NZ]

You recognize the problem and have answered your own question yourself: servo action and applied leverage.


But what I find hard to comprehend, is why you 'fixed' something with extensive re-engineering, that only required correct establishment of existing components, and to have put up with a potentially dangerous situation of your own creation for +15 years, and then ask for assistance here???

[ric]

Perhaps the brake arm and brake cam needs to be seen as a one time only assembly. The two parts should start off with an interference fit requiring the 26tpi nut to force the parts together, but once disassembled end up with a push fit and therefore more likely to spline strip.

[Adrian]

Perhaps a hydraulic conversion? There might be a slave cylinder for a SLS car brake you could adapt to use with the existing shoes, as these have had these properly set up. A.

[p]

By the way - looking at your pictures - I have the lever the other way round... ie inset inwards as it's neater and also pulls within the radius of spindle bush nearer the load (cam).

[Count Johnny]

Hi Tim



If you take a look at what you can see of the frame, you'll see that it is very much non-standard (rigid, raked to 35 degrees, rides at about 2.5" from the ground) and was originally designed for a QD hub operated by a cable attached to one-off foot controls - so it wasn't a merely a matter the "…correct establishment of existing components…"



For the avoidance of doubt, there was nothing "..potentially dangerous…" about Slo Poke's previous rear brake, but I wanted to ring the charges for aesthetic reasons by fitting half width hubs at both ends.



Anyhoo - while this proved to be one of the most challenging of the changes that we rang - you'll be pleased to hear that, after a little fettling on Sunday, the new rear brake is jolly lovely and I'm confident will be permanently as safe as houses, by Thursday of this week (see below).



This said - much like your 2LS adjustment process - I'm sure you're correct in theory.



Thought I'd post this should you have trouble spitting out any Cornflakes:





Hi Ric



You're probably right and, on Sunday, I made a point of perfectly aligning the teeth, once only, before carefully pressing the lever on.


Hi Adrian



I'm of the view that hydraulics (on motor bicycles) are the work of the devil.
Hi P



You're right (and I would preferred to have located it in this way) but the rod would foul the frame in this position.


Hi All



By way of an update: On Sunday, I discovered that the figure of eight piece in the second image was fractionally too small, thus still allowing the hub to rotate a smidge which - under emergency braking - forced a spline or two.



Temporary adjustment for this - followed by a spirited 100 mile ride out into the sticks - indicates that everything is fine, with this arrangement, so I'll whizzed a CAD file over to the laser cutters for a slightly longer figure of eight.