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Discussion Starter #1 (Edited)
I'm trying to determine if I need front brake work done on my 67 TR6R. What should I expect in terms of stopping power from this stock drum brake? I'm used to the disc brake on the 73 Bonnie, so I don't know if it's just a matter of adjusting myself to this style, or adjusting the brakes themselves (or some of each). I do know enough to not expect the drum to stop the same as the disc. :cool:

It stops OK, I just need to get on the brake earlier and squeeze a lot harder. I do still need to check the shoes to see if they are worn/glazed. The mechanism itself seems to be working fine.

What do you think? In good condition, what should I expect from 42 year old drum brake technology?

Best Regards,
Joseph
 

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Seattle73, My 67 Bonnie stops just fine. However not quite so fine as disc brakes. I don't think it's possible. If your shoes are original, you might want to replace them. When I disassembled my Bonnie for a rebuild, I found the old shoes to be worn and a bit crumbly. I don't run the old girl flat out any more, so I don't need to stop quite so quick. I find that old age and old bikes are a good combination. Carl
 

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If you fit a 1968 -1970 twin leading shoe backing plate, your drum brake can be very good, provided that it is adjusted correctly.

I have both a T140 with disks and two 1970s, a 500 and a 650, with the TLS drum set up.

The TLS is nearly as good in the dry and better in the wet than the disks the first few times they are used.

However, when hot, the disks ar far less likely to fade like the drum brakes do.

Even the stock 1967 single leading shoe brake can be improved by careful set up and good shoes.
 

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I'm wondering this exact same question. I really, REALLY, have to squeeze to get any serious stopping done. And when I say squeeze I mean 3/4 past, almost a full brake handle engagement.
 

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Something is not right if there is that much lever travel.

Worn shoes or drums could be the cause or there could be a part missing where the cam rides on the brake shoe.

In any event, if you compare your brake with the parts manual to be sure all the parts are in place and then measure everything, the problem should become apparent.

The condition you describe could get worse and result in the cam going "over center" such that it would not release the brake when you release the brake lever, a very dangerous condition.

Good luck and be safe.
 

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Discussion Starter #6
I inspected all the cables closely last night and they look to be original equipment (and not in very good condition). I lubed the brake cable and it seems to move more freely. Definitely needs to be replaced, though, as I learned from the clutch cable which snapped an end off as I checked the action after making some adjustments to the tension.

I'm going to inspect the brake shoes tonight.

Love the adventure of these old bikes!
 

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67 was the last year for the old single leading shoe setup, and with good reason. About 1962 was where the speed and capability of the bike overcame the brakes installed on them 'till 68.

You can get NOMINAL performance out of them by carefully skimming the drum, fitting new shoes with heavy duty modern compound linings (believe it or not, I like Emgo just fine), fit up a heavy duty Venhill, Barnett or Doherty cable, and adjust it to where the shoes JUST start to touch the drum on free spinning (support front of frame to get wheel off the ground).

P.S. - clean, polish and grease the actuator pivot pin!
 
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