Classic cars forum & vehicle restoration.

[enryte]

Hi,
Has anyone got a Riley RMB front hub and backplate complete with cylinder and shoes that I could borrow to take some measurements? I would of course pay all transport costs. I'm near Bury St Edmunds, in Suffolk.
Here's hoping....
enryte

[Uncle Alec]

Need to know the year of the car and/or the diameter of the drum. There are three possibilities.

[enryte]

Hi Uncle Alec,

Well, it's actually a 1926 Hillman 14 that has 12" mechanical brakes at the front. I want to convert them to hydraulics because I'm putting a more powerful engine in.
All I want to do is see how everything is positioned on the backplate so I can then make up my own plates to suit the Hillman hubs. I understand that the early RMB's had a different set-up to the later ones because of the hyro-mechanical system - later changed to full hydraulics all round.
So, I suppose that the early front backplate would be more relevant as I intend to retain cables to the rear brakes and work out a compensator arrangement to accomodate.
Is this a tall order?

enryte

[Uncle Alec]

Early RMB brakes - both single-cyliner and TLS - are very hard to get, and the cylinders even harder.
Later 11" brakes are easier, and cylinders commonly available. They are also better brakes as the shoes are wider.

[enryte]

Hmm, I beginning to wonder about the wisdom of all this - I could find myself up a gum tree without a paddle. I think I'll reconsider. Very many thanks for your input - I think I'll step back from the brink and look at something more akin to servo assist on the current system. I know the Clayton-Dewandre servo was an optional extra on the 14 - my '29 tourer has one - and the stopping power is streets ahead (so to speak) of anything else I've driven of that age. On the '26 set-up a servo would be difficult to incorporate but, as I'm seeking only to increase the effectiveness of the shoes at the drum and to reduce the load on the pedal, perhaps modern lining material and a bit of hydraulic assistance further back down the system might suffice.
Thanks again,
enryte

[Uncle Alec]

I'd consider the hydro-mechanical master cylinder as used on Riley and Jowett. It should be easy to link up to a cable rear; it is linked to a rod rear braking system on the RMs.

[enryte]

Aha! I didn't know that the Jowett had the hydro-mechanical system and, as luck would have it, in the workshop next to mine, the restoration of a Jupiter is under way. The body is off and the chassis exposed. I was looking at the brake arrangement the other day but it just didn't click! I must be half asleep.

More info on the project at www.nigelhamlinwright.wordpress.com.

Thank you once again.

enryte

[PAUL BEAUMONT]

No, Enryte you wern't, the Jupiter is full hydraulic. Early Javelins were Hydro-mechanical, but again the master cylinders are scarce and expensive! What about Austin A35 or something of that era? you would have to resolve the issues of that sliding cylinder, but I would have thought parts would be more plentiful.

Paul

[enryte]

Thanks Paul, you're absolutely right on 2 counts; the Jowett and the good sense of looking at something more readily available. I'm going to revisit the Hillman hubs and see if I can't mount a cylinder which would operate the brake lever perhaps - it all needs some careful thought.
enryte