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Evogone
26-03-2010, 13:45
Had the rallycar MOT'd and the rear brakes were low effort on both sides. Can not remeber the scale its measured in bit was law. I have the Acon 4 pots on the front and the pedel feels nice and firm and they lock the wheel very easily and very progressive.

I obtained the same figures using the hand brake and the footbrake. Just have new sics and pads (DS2500) and the calipers seem fine (plus they are equal effort either side).

Is this the brake valve that needs adjustment or cause both handbrake and footbrake are low effort it means something else..?
katbloke
26-03-2010, 14:46
Check the bias valve returns back sometimes they stick or fail completely
northy
26-03-2010, 15:07
if u have spare cash treat the car to a new bias valve - mine transformed my rear brakes.
Evogone
26-03-2010, 15:09
if u have spare cash treat the car to a new bias valve - mine transformed my rear brakes.

Whats the part number i think the ABS and nonABS ones are different...
Evogone
26-03-2010, 15:33
if u have spare cash treat the car to a new bias valve - mine transformed my rear brakes.

On the cup car ?
katbloke
26-03-2010, 18:54
Standard is

77 00 840 561 Compensator/Brake
schakal
26-03-2010, 19:03
convert it to drums , no bias valve required and handbrake
works mliions times better :D
Evogone
26-03-2010, 19:08
Standard is

77 00 840 561 Compensator/Brake

Is that the ABS one ? mine doesnt have ABS
katbloke
26-03-2010, 19:40
All my dialogies are based around the year details of 94 so id say no
Evogone
26-03-2010, 20:45
Anyone know the different part numbers ?
Justin..
26-03-2010, 21:05
Woulda thought they're the same tbh ?
northy
27-03-2010, 22:57
they are the same
MAXIBOY
27-03-2010, 23:02
i would fit an adjustable bias on a rally car and up the rear effort to match the fronts..
Wobba
27-03-2010, 23:30
i would fit an adjustable bias on a rally car and up the rear effort to match the fronts..

Same here! Thought you would have done that by now Evo ;) Now send me that exhaust please :D
stan
28-03-2010, 11:02
Don't over do it, the mot station are testing fir road usage, they are going on guidline figures which are for road cars....not lighter race cars with different requirments.

I'd be tempted to leave it.

When I fit 4pots I've always found I need to incease bias to from as the rears lock up in STD bias.

If your fronts are locking up maybe you need to lock at suspension set-up and tyres.
Evogone
28-03-2010, 11:17
Think its the new pads not bedded in as its the same brake force reading with handbrake and footbrake..was Ok before these went in.

Will have a bleed of the brakes making sure the rear beam is loaded up and give the pads a roughing up..!