410 Handbrake
My 410 has "always" been somewhat on the edge when it comes to achieving the stopping power required of the handbrake for the MOT test (for those outside the UK that is the official name for the annual fit-for-purpose test), relying on a sympathetic tester with a very strong left arm to get a pass.
I had been wondering about this situation when the same sympathetic tester suggested it might be cheaper to get the handbrake pads relined rather than buy new. This wasn't actually the case but it did allow me to specify a "soft" material for the pads, reckoning that I needn't worry about brake fade but it would be nice to have a handbrake that might stop the car in an emergency.
My word it's made a difference. I know we in the UK no longer have to worry about an MOT pass on cars over 40 years old, but the fit for purpose requirement still stands and the handbrake is now fully fit for purpose.
But here is another problem.
Whilst inspecting the newish soft handbrake pads the other day with the same sympathetic tester we noticed that, whilst the callipers open and close with ease and the return springs work perfectly, the callipers themselves are slightly unbalanced. This unbalance causes the inside pad to just touch the disc, on the heel of the pad, whilst the calliper is open. The pressure is infinitesimal, but this contact would explain why one pad wears asymmetrically, which I attempt to show in the attached photo (which is of a "hard" pad material)
This wear pattern means that the effective surface area of one pad on each caliper is significantly reduced over time, making it harder to both meet the MOT requirements and to stop the car in an emergency.
We have tried to balance up the imbalance with the aid of a very light spring, but I doubt that this will provide a long term solution.
I would be very glad to hear from anybody who has experience of this latter issue and has come up with a long term solution.
Roger Morrall
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