Two handbrakes- would this work?

[biosurf]

Been thinking about improving my Surf off road. When I did a couple of hours offroad training ewith John Morgan earlier in the year he was chatting about mods and mentioned that some of the guys who compete have'fiddle brakes' fitted. Basically hydraulic brakes that can brake only one rear wheel at a time allowing the vehicle to turn on its own axis etc.
Thought no more of it.

Then I weas thinking the other day that I read that if you lose traction on one wheel on an axle with an open or limited slip diff, if you use the foot brake a bit it can create a sense of traction in the wheel in the airand make the driveshaft transfer some of its drive to the one still on the ground. It even talked about how in extreme situations you can try and wrap, say a tow rope around the spinning wheel (once its not spinning, natch ) and this will mean drive goes to the other wheel.

Would it work if you modded the surf so it had two handbrakes, each with a seperate cable going to one of the rear wheels? By my thinking this would mean that when one rear wheel; lost traction you could pull the brake and the drive would be used for the wheel still on the ground? Its not perfect but I can't see me ever having the money to sink into a diff lock or anything like that and this would seem to be at least part of the way there and could at least get you out of a cross axle situation?


You need only one handbrake for the MOT so I'm thinking that you have the means to put both cables into one of the levers before MOT?

Searched and cant find anything on this on the site which I'm guessing means theres a really obvious reason why this wont work that I'm missing because I'm a mechanical numpty?

Any ideas?

[Chillitt]

Milners do a fiddler brake set up

[Apache]

Searched and cant find anything on this on the site which I'm guessing means theres a really obvious reason why this wont work that I'm missing because I'm a mechanical numpty?

Any ideas?

You aren't missing anything. Being able to brake wheels individually has been around for years in trials cars / 4x4s. Not sure of the legality of a fiddle brake system on a road vehicle though.

Could work out as a cheap alternative to difflocks.

[nero279]

I could be wrong, but i though the legality thing was for two reasons 1 being the handbrake has to be independent from the footbrake, which would basically mean having two sets of slave + master cylinders to have a hydraulic handbrake which operated independently of the footbrake, and also that it must lock in the 'on' position, fiddle brakes used in trialling and such return to the off position when you let go of them.

I also thought it had to operate on at least 2 wheels, but i'm not sure quite how that stands with the x-brake, which seems to be becoming increasingly popular. I know it does stop both wheels because it works on the prop, but independently?

[Gamedawn]

I could be wrong, but i though the legality thing was for two reasons 1 being the handbrake has to be independent from the footbrake, which would basically mean having two sets of slave + master cylinders to have a hydraulic handbrake which operated independently of the footbrake, and also that it must lock in the 'on' position, fiddle brakes used in trialling and such return to the off position when you let go of them.

I also thought it had to operate on at least 2 wheels, but i'm not sure quite how that stands with the x-brake, which seems to be becoming increasingly popular. I know it does stop both wheels because it works on the prop, but independently?

I'm not sure about the legality of tapping into the brake lines (can't really see why there should be a problem) but if you have hydraulic fiddle brakes there is no reason why you shouldn't retain the cable operated handbrake in order to stay road legal.

As to the legality of transmission handbrakes, there's a little known manufacturer of off-roaders from Solihull that's been using them for years

[biosurf]

I know this is really showing ignorance but does the handbrake work on the rear wheels and is it via a cable (I think this is all the case but this is moe so could be anything!)

If it does, then my thoughts were more to have a seperate cable for each side each run to a seperate handbrake lever with a pin to link them or with the ability to run both cables into the one handbrake when you're not offroad?

Otherwise I've been looking and see that you can get brake line locks that sit in the hydraulic lines connected to a solenoid. You depress the brake pedal to pressurise the lines, flick a switch mounted on the gear stick to lock whichever side you want locked, then release the pedal and that side will stay locked on until you flick the switch back. These are often used for burnouts or to warm up the rear tyres before racing.

http://www.hotrod.com/howto/49619_br.../photo_07.html

would something like this be another option or is all this (i.e. cheap and legal alternatives to lockers) too good to be true?

[biosurf]

*shamelessly bumps thread and sneaks away*

[Vagrant No2]

We had hydraulic handbrakes fitted on the rally cars when I co drived years back . By law they had to have a lock out fitment for road use but it is not an offence to have a system fitted as long as you can prove it is not used on the road . Not the same as fiddle brakes but still a mod to the braking system .
That was about 7 years or more ago , but I dont think things have changed from then .

[surfenstein]

i had an idea months ago,and that was to bring the single rear brake line inside the cab around the centre consul area,tee this off into two lines and fit two separate ball valves one to each line and then plumb these two lines down to each rear wheel.thus giving you a seperate line lock for each rear wheel.simple cheap and easy to modify.

[Chillitt]

http://www.milneroffroadracing.com/brakes.pdf