front brake Arrrgh

[clive cooper]

Hello all
after a succesfull first topic about the gearbox cover,a query about the front brake(or lack of),doing a few miles on the scott now and I am getting used to no engine braking,and so rely more on the brakes,the bike is a 1949 scott ,I have stripped the front brakes down and also the compensator on the front mud guard ? all clean and working well ,rear brake great front brake makes all the right noises but fails to do much in the stopping dept,
so the question is are there any mods done by members to improve the brake without altering the look of the bike,
cheers Clive

[David J Waring]

Has someone put the front wheel in “back to front” ?
The brake levers emerging from the alloy brake back plates should point backwards.
Or has there been an oil leak from the Dowty forks which has found it’s way into the drums. My 1947 Flyer is currently off the road, with rags tied around the lowest (chromed) parts of the forks to guard against the possibility of this happening.
The front brakes on this machine are quite reasonable for a heavy machine, albeit a long way from modern discs.

[clive cooper]

The wheel is correctly fitted brakes are dry and in good condition.I suspect the outer cable on all three cables may be compressing, this has been a problem on other bikes I have.
waiting for your opinions
white knuckle clive

[NickPoll]

Hello, Is the cable inner & outer thick enough gauge ? I’ve often seen machines with the brakes cables too thin, making the feeling spongy and not working. Try using a thicker cable if possible and oil it well. I’m sure it’ll make a big difference. regards, Nick.

[Mike Fennell]

Have you looked at previous threads on this brake? Most recently by gammakeith October 25 and November 15.

There is a wide range of opinion on the standard set-up – from, “the best drum brake I have used” – to, “it’s OK for the period” – to, “the brake that doesn’t work” – and, ” the confounded thing !!!” The latter comments tend to predominate.

My opinion – it can be made to work almost as well as it looks by doubling the leverage, in one way or another. A Vincent-style balance arm does it but requires extensive modifications and looks totally foreign. Retaining the original appearance, the best bet for now may be to halve the pivot offset at the handlebar ( gammakeith’s method, but he has twin cables and a compensator at the handlebar – Brummie system. Not quite so simple for a single cable, but do-able I think )

These solutions all double the handlebar lever movement and also double the forces in the system, so your thoughts about heavier cables are very relevant. It will inevitably feel more spongy, but you won’t mind that – given the much improved stopping.

[clive cooper]

cheers all
been out on the bike for a couple of hours today dry but cool,maybe me but brake seems to be working better or I am getting used to the driving style and leaving more room for braking.(less of the white knuckles and a more relaxed ride,corners very well)
think I will try the heavier cable for now for the quick fix,also look back at previous brake related threads for other suitable methods
thanks
Clive

[Roger Moss]

Hi Clive If you take the wheel out and look at the linings, what percentage of the linings has cleaned up? If the drum is glazed, a rub round with some medium emery cloth can help it bed down. I use two cables from a lever mounted compensator, but have reduced the cam width to increase the applied effort. To set up a brake for optimum efficiency is a bit time consuming. Make sure drums are true. Skim if not. Measure size. Put new racing grade linings on shoes over thickness. Put 0.010″ shim on top of cam faces. Turn linings to same size as drum. Take out packers, Chamfer linings but leading edge at 45 degrees as you want some self servo. Then you have done everything so after that you only have the power of prayer.

[timetc]

Try Safetek they have a good racing lining and will put it on thick for turning
Always use it on my Vincent brakes
Do up your nuts with brake on to ensure concentricity
There is also a school of thought (and belive me in the VOC compensators have been talked to death) that after a short while so long as the pull of the lever is split the wear on the linings will equal the pressure to each shoe set.
Finaly ensure you have a good handlebar lever fitted firmly with the maximum leverage twixt pivot and nipple

[chris wastell]

Its well worth getting the shoes re-lined with a modern soft material, old linings are too hard. The scott set-up works perfectly if set up properly and the shamfering idea certainly helps, it was Tich Allen wrote about it several times

[jampotrdann]

the problem with old bike braking is about 90% due to the drum worn and only the middle of the shoe making contact with the drum, i had mine fitted with lineings thicker to fit the drum .they work fine now https://www.saftek.co.uk/

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