Rear brake lock-up

[Geoffrey Lord]

Hi,

Has anyone a fix for the self locking rear brake on my '53 VB plunger? I can apply the brake quite hard and it's fine but then other times a touch on the brake pedal to scrub off a little speed and the whole shebang locks and the lever is sucked from under my foot. Quite scary! I have tried stronger shoe springs and different settings of the conical adjuster, I have even tried an additional, temporary return spring on the lever itself.

Is shoe material a factor? I have ones with the embedded brass (?) elements.

[Pete.Silson]

Have you got a downward pointing brake arm (like the first picture)?

If so, then this is a well known problem and can only really be cured by changing to an upward pointing brake arm.

I am fairly sure both the pictures above are of 1953 Anstey Ariels.

Pete

[Geoffrey Lord]

OK, That is interesting! Yes, it is downward pointing. I wonder why changing to upward pointing works?

Geoff

[Vincent.vanGinneke]

The combi of the plunger springing and the direction the cam on the lever pushes the shoes makes for a self servo action when the rear brake is applied.
A factory mistake !
Routing the rod with the arm pointing up is a bit difficult, some models used a cable after this was found out and you need abutments for that I think only the later SQ4's had that.

[Geoffrey Lord]

Thanks for that, it all makes sense now. I will work out a fix.

Cheers

[simon.holyfield]

Thanks for that, it all makes sense now. I will work out a fix.

Cheers

When you make the brake rod for your new upward pointing arm you will find the routing quite difficult I have multiple small bends in mine to get it around the suspension and the brake light switch but once it's sorted it works pretty well. It's not quite as solid as a properly straight brake rod but it's perfectly acceptable.

Shout if you need pictures.

[Roger Gwynn]

All 53 plunger models have a cable operated brake. See the full story here. https://draganfly.co.uk/product-categor ... -sprocket/