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[PO51UHD]

Hi All, still (slowly) rebuilding the '59 Comnie. Rebuilt the front brakes recently and they're not working well enough. With full lever pressure I can still just push the bike forwards, and I'm assuming this won't do! My brake rebuild consisted of stripping, cleaning, lightly greasing the operating mechanism, fitting 2/3 rivets which were missing on linings (the linings still had a good thickness of life and had obviously bedded in, but I lightly abraded the glazed braking surface anyway). The shoes are welded pressed steel, which I haven't seen before... Everything went together fine, and I left the sliding pivots very slightly slack, relying on the spring washers to work their magic and centre the shoes. I've adjusted both cables and am getting similar tension on each (witness the see-saw cable mechanism on the lever sitting perpendicular to the cables when pressure is applied. There's a bit of 'sponginess' in the feel of the lever which suggests something ain't bedded in right? Any ideas for improvement please? Thanks. Stephen

[another Allan]

In my experience, sponginess is often due to cable stretch, so thicker cables may help. Rivetted linings which have been re-rivetted may also be a factor. If the linings are not in 100% contact with the shoe, then some 'lost motion' could arise there. Then there's the matter of the shoes. I had a Constellation when I was 13 (it's a long story....) and I'm pretty certain that the shoes were cast alloy. Are your shoes correct, or adapted from some other use? Also, have the brakes ever worked properly in your ownership of the bike?

[PO51UHD]

Hi Another Alan
Thanks for your comments. I bought this bike as a project so have never tested the brakes. Cables seem ok (thick and seem relatively new). Interesting about cast shoes - these are the first fabricated ones I've ever seen... I ensured they went back in the same positions relative to each other and the back plates, so I'm pretty sure they're as they were when I got the bike...
Stephen

[Gwilly]

Question,, Why where some rivets gone? suggests movement of the material under breaking… Give rise to sponginess maybe.. should the shoes be bonded and the rivets are a belt and braces approach?? Does the steel flex maybe?? Too important to ignore the signs, get shot and obtain some known good ones… my twopenneth..

[Gwilly]

Or even braking, maybe both are correct...

[Norm]

Hi Stephen seems like your brake is better than on a Meteor I was building. I could push the Meteor uphill with the brake on and that was after I spent $300 on linings.First set complete rubbish, second set imported from the UK as some special racing linings were not much better

[Mark M]

Stephen, the pressed steel shoes were originally fitted to the 6" front brake Bullet models and then the very first 700 Meteors (1953-55) which had the first double sided hubs. They are truly dreadful and can (should!) be replaced with the cast alloy shoes fitted to all the 6" brakes subsequently used on anything from Crusaders to Connies. This will improve braking massively as I found on my own 53 Meteor. However, the double sider will never be a fierce brake, it's better at scrubbing speed rather than urgent deceleration. I have managed to lock the front wheel of my Meteor in emergency though so it's not all bad!
REgards, Mark

[PO51UHD]

Hi again, and thanks to all for the suggestions. I think I'll go the new shoes route! Stephen

[Adrian1]

http://www.accessnorton.com/drum-brakes ... lit=norton

[Anders F. R.]

I suppose that the single sided 6" SLS front brake on my model G is the same as half of your double sided brake? If so, it should be possible to make it do a much better job than it is now! Obviously it will take some use bedding in the linings after you have had the brakes apart and removed the glazed surface etc., but still. .-.-.-.-.-.-.-.- I too have riveted linings, fitted new 12 years and 6-7000 km ago. Can't rememeber at the moment if my brake shoes are alloy or steel, but can find pictures. Anyway, the front brake is much better than useless, and the rear brake which is just the same can lock the wheel on dry tarmac. .-.-.-.-.-.-.-.- Experience has thaught me that drum brakes are very sensitive for any deviations from a perfect setup. The smaller the brake is, the more important a perfect setup gets. Any slack, wear, misalignment, out-of-true, wrong brake arm angle or partial contact between linings and drum will have a major negative effect on brake performance. .-.-.-.-.-.-.-.-.- Anyway: In your case I don't thing it is only a matter of bedding the linings in again. It sounds like something more. Good luck finding it! Regards, Anders F. R.