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Semi-Girling brakes
#19
Hi

I am still puzzled by this.

The advantage of semi-girling is that the smaller cams and longer levers give more leverage, so that for a given cable tension more force is applied to the shoes for more braking force.  The downside is that lining wear has a more pronounced effect on pedal travel, so there had to be an easy way to re-adjust at each wheel without messing about with cable lengths as used to be the case. Hence the square headed adjusters.

With shoes adjusted for minimal running clearance and brakes off, the flat cams will be at their minimum position and will sit vertically between the steel plungers.  The lever should then be more or less vertical, and the machined cotter pin slot more or less horizontal, so the slot will be at right angles to the cam.  Presumably one has to factor in the need for the levers to actually be slightly ahead of vertical when off, so that with their (small) travel they are truly vertical when on. Also, one has to allow for the small taper angle of the cotter pin. The cam on the left of your photo is therefore what I would expect to see. The cams are handed left and right, and don't forget that rear cams are also different to fronts.  The heads used to be stamped with letters to identify them.

Lining thickness shouldn't upset the above, provided you can still adjust for the correct running clearance ( which you can - just ).  Clearly, if you had thinner linings and deliberately mis-adjusted them for a large running clearance you could make the levers travel more between the brakes off and brakes on states, so that they would be vertical with the brakes on.  But this isn't how they are supposed to work and would give you a very long pedal travel.

The photo below is of my own setup, the levers are from Seven Workshop but I cannot remember the source of the cams. The handbrake is on (which fully applies the rear brakes and lightly applies the front brakes) but the travel from off to on is pretty small.  As you can see, the lever sits more or less vertically and the cotter nut is to the rear.
   
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Messages In This Thread
Semi-Girling brakes - by falcott - 28-06-2024, 09:44 PM
RE: Semi-Girling brakes - by John Cornforth - 28-06-2024, 10:34 PM
RE: Semi-Girling brakes - by falcott - 28-06-2024, 11:27 PM
RE: Semi-Girling brakes - by John Cornforth - 29-06-2024, 08:01 AM
RE: Semi-Girling brakes - by falcott - 30-06-2024, 12:39 AM
RE: Semi-Girling brakes - by Tony Press - 30-06-2024, 03:12 AM
RE: Semi-Girling brakes - by John Cornforth - 30-06-2024, 07:38 AM
RE: Semi-Girling brakes - by Malcolm Parker - 30-06-2024, 08:42 AM
RE: Semi-Girling brakes - by falcott - 30-06-2024, 09:15 AM
RE: Semi-Girling brakes - by Tony Press - 01-07-2024, 01:41 AM
RE: Semi-Girling brakes - by stuartu - 01-07-2024, 10:32 AM
RE: Semi-Girling brakes - by Reckless Rat - 01-07-2024, 02:23 PM
RE: Semi-Girling brakes - by falcott - 03-07-2024, 02:53 AM
RE: Semi-Girling brakes - by Ian Williams - 03-07-2024, 05:01 AM
RE: Semi-Girling brakes - by Ruairidh Dunford - 03-07-2024, 10:13 AM
RE: Semi-Girling brakes - by falcott - 04-07-2024, 03:34 AM
RE: Semi-Girling brakes - by Howard Wright - 04-07-2024, 06:52 AM
RE: Semi-Girling brakes - by Stumpi - 04-07-2024, 08:35 AM
RE: Semi-Girling brakes - by John Cornforth - 04-07-2024, 09:44 AM
RE: Semi-Girling brakes - by Ruairidh Dunford - 04-07-2024, 11:37 AM
RE: Semi-Girling brakes - by Ian Williams - 05-07-2024, 03:37 AM
RE: Semi-Girling brakes - by falcott - 05-07-2024, 07:06 AM
RE: Semi-Girling brakes - by Ruairidh Dunford - 05-07-2024, 05:03 PM
RE: Semi-Girling brakes - by Ruairidh Dunford - 05-07-2024, 05:05 PM
RE: Semi-Girling brakes - by John Cornforth - 05-07-2024, 06:39 PM
RE: Semi-Girling brakes - by Ruairidh Dunford - 05-07-2024, 07:38 PM
RE: Semi-Girling brakes - by Ruairidh Dunford - 05-07-2024, 07:41 PM
RE: Semi-Girling brakes - by falcott - 05-07-2024, 09:01 PM
RE: Semi-Girling brakes - by Ruairidh Dunford - 05-07-2024, 09:19 PM
RE: Semi-Girling brakes - by falcott - 22-07-2024, 01:20 AM
RE: Semi-Girling brakes - by David Stepney - 22-07-2024, 08:35 AM
RE: Semi-Girling brakes - by John Cornforth - 22-07-2024, 11:52 AM
RE: Semi-Girling brakes - by Ruairidh Dunford - 22-07-2024, 01:46 PM
RE: Semi-Girling brakes - by `Gordonhbm - 22-07-2024, 04:28 PM
RE: Semi-Girling brakes - by John Cornforth - 22-07-2024, 07:13 PM
RE: Semi-Girling brakes - by falcott - 22-07-2024, 08:51 PM

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