Author Topic: Rear Brake Anchor Point.  (Read 1110 times)

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mx250

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Rear Brake Anchor Point.
« on: October 15, 2009, 10:10:34 am »
'Back in the Day' there was much discussion in road tests etc about the anchor point of the rear brake and it's effect on handling in general and brake hop under braking in particular. IIRC, the general census was that a 'full floating' rear brake (with the backing plate free to turn and anchored directly to the frame) was 'the go'.True or false?

Was 'brake hop' a function for poor suspension or was it other issues like rod operated brakes.

Another way of putting the same question, are full floating rod operated rear brakes better than cable operated non-full floating brakes? (I note that moderns have almost exclusively non-floating arrangements (with fluid braking actuation)).

(The reason I ask is that I'm playing mix and match at the mo with some old wheel/brake combinations ::)).

Offline Nathan S

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Re: Rear Brake Anchor Point.
« Reply #1 on: October 15, 2009, 10:29:07 am »
The simple answer is that no riders of mortal skill levels ever seem to notice any difference between any of the possible set-ups. I'm open to input from people with talent who might be able to feel/appreciate the difference.

My understanding of the theories:

1. A floating rear brake should isolate the rear brake from the suspension movement. Its interesting to note that Yamaha used a floating rear brake on some of their larger capacity trail bikes (DT1, DT360A etc), but didn't bother with them on the YZs until the long travel 1979 models - I'm sure that there's a lesson in that - but being Yamaha, you can't tell how much of it was for real reasons, and how much was about marketing/gimmickry...
2. A cable rear brake is about packaging more than anything, AFAIK. A cable makes cross-over (pedal to brake) arrangment a lot easier, and also removes the need for the pedal-rod pivot to be at/near the swing arm pivot. Cables also seem to take a bit of the 'edge' off the brake operation, which would probably be a good thing for a lot of bikes (ie: old Yamahas)...

Its probably worth noting that cable operation, and floating set-ups are pretty much unrelated - you can have either, neither or both.
« Last Edit: October 15, 2009, 10:30:41 am by Nathan S »
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Offline BultacoMacca

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Re: Rear Brake Anchor Point.
« Reply #2 on: October 15, 2009, 12:59:32 pm »
Looking at most later model disc brake bikes, they have a fixed slot for the caliper setup, and probably could go to full floating if they thought it warranted it.
I'm going to try a short brake backing plate stay on my latest Bul, but I'm making sure the brake pedal/rod attaching point up the front is nearest to the swingarm pivot as possible.