My car has semi girling brakes on the front.
Is it better to use short levers or long levers?
I appreciate that long levers offer a mechanical advantage but the problem to me seems to one of limited travel, which possibly favours a shorter lever and a heavy right foot.

Does anyone have an opinion?

Thanks

Charles

I have fitted the shorter ones working on the principle you have highlited above. System works well like this.

Good luck,

Ruairidh

Charles, nothing to do with brake levers but do you have any pictures of your car? It sounds interesting.

Particularly the 10 stud engine / supercharger.

Guessing that it is an Ulster / TT? replica...

Sadly not a 10 stud engine. Just a standard 1925 engine converted to blown spec.

Some photos





and I wrote an article for the VSCC bulletin about its' construction (incase you're not a member which you probably should be!)

Here are the 3 pages






Charles

Ruairidh

Thanks - that's what I hoped someone would say!

Charles

Thanks Charles, that is brilliant. Gives me something to read this evening.

As for the VSCC, I really should join, (I have to clear two lockup garages first though to justify the cost!)

Charles,
As you suggest long levers need greater cable travel to take up any slack. It's all a balancing act, literally. You should consider the whole of the braking system if you're wanting to redesign. If your cross shaft doesn't compensate you've got to think about the back and front levers together - have you got too much (unlikely!!!) or too little braking at one end or the other. Shortening the levers will make that end come on earlier in the cable travel. As you say you can always press harder to get the retardation. Personally I'd rather adjust out all the unnecessary slack at the shoe ends etc and use a longer lever. Then with long levers the brakes come on at the same amount of pedal movement but harder and more progressively with more 'feel'.

There's information about all the lever lengths and some photos on the Speedex website. Two separate brake threads in one weekend - a hot subject this weekend!

Dave

On a similar vein, my set up uses standard pre Girling parts, and works OK ish, BUT does suffer from a cable related problem.
The first application of the brakes causes pulling to the left, and after this the next application/s are OK and it pulls up true. I think maybe that the blancing beam for the front brakes is the cause? The rear brakes are not balanced with any mechanism, they just use the standard cross shaft, which of course is balanced front to rear by the concentric shafts. Any problems with the static settings would be apparent all the time I would think, so I am left with the front cable and balance beam perhaps sticking I think?? .

Steve

I used to own the Rolt Ulster built up by Stuart Rolt in the 60's and used by him ,Barry Clarke and Martin Eyre in VSCC racing winning some 8 Voiturette Trophies and this has Semi Girling brakes which were very effective.However when built up by Stuart he went to great pains to SHORTEN the front levers .I queried this with Martin and he confirmed they were more efficient that way.

All very interesting stuff chaps. A diverity of opinion as expected.

Anyone care to scan Jack French’s two articles "The Power to Arrest" in the A7 Clubs Association 1981A & B editions and either load them onto Flickr (or similar) or email them to me? It's mentioned on the Speedex site and Jack French's stuff is always worth reading.

Charles

I do not advocate one type of braking system over another.

All the sevens I have on the road at present have different braking systems, I drive them all accordingly and, in my opinion, the best and most effective way to stop your car safely is to know it and assume nothing! The systems and my own thoughts on these are as follows:

Mk 1 Pearl Cabriolet: This has a coupled Austin system with off-set brake shoes. It is very effective, gives a smooth action on the pedal and once balanced correctly only requires the odd turn on the wing nut adjuster to maintain effective braking. I tow the mini caravan with this, which is not braked, and the system copes well.


’28 Chummy: This car has the original uncoupled system running on narrow brake shoes. The brakes work well and being uncoupled are easier to balance. I also find it comforting to know that if just using the foot pedal is not sufficient then I can add 100% more braking by using the handbrake. If you are descending long hills, such as we did in Norway this summer, you can alternate between handbrake and footbrake keeping both relatively cool and efficient.

’29 Saloon: This car was converted to a hydraulic system in the late 1950’s and is largely based on a Morris Minor system. The car brakes in a perfectly straight line, the pedal is quite hard and efficiency is good. I do find, however, that a lot of adjusting is required to keep the system working properly, this, I feel, is largely due to the relatively short movement the brake pedal makes compared to the Morris it came from. Having noted how well the system works I do not think that I would go to the bother to convert any cars that have cable systems, if you loose your hydraulic brakes you are stuffed, a broken cable will at least still allow two or three brakes to continue working in an emergency.

’30 Ulster Replica: This car uses an Austin coupled brake system with Girling back plates, mechanisms, shoes and drums on all four brakes. The car has a soft pedal that works very well indeed. Again, once this has been set up and balanced correctly the system is very efficient and only requires the odd turn of the butterfly nut. There is some work involved converting the back axle to take Girling back-plates, but the fronts can be fitted easily to an early sports beam.

My father’s ’29 Chummy has standard uncoupled system but he has fitted a Girling axle, stubs, mechanism, shoes and drums to the front. This works very well if you need to stop quickly.

I have a 6” braked car but have never driven it on the “road”, once it is roadworthy test drives around fields tell me that driving this will require longer stopping distances and the usual awareness of what is going on around you.

Take the time to really know your car, it’s braking (and other) idiosyncrasies and drive it accordingly.

Good luck

Ruairidh

p.s. I will post photos of the hydraulic master cylinder position later this week.

My scanner has packed up, but if nobody else comes up with scanned copies of these two interesting articles, I would be happy to send you photocopies if you let me have your postal address.

John

Thanks John but Stuart Ulph has already offered to scan them for me

Regards

Charles