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peddle box help
andrewturner - 20/6/07 at 06:53 PM

Can some please help.
I made up my own peddle box with adjustable brake bias, but have a problem, when I brake the 1st time I push the peddle I get very little on the front if I push again I get the front working properly. I have tried all settings and nothing seems to help. Could it be that I do not have enough leaverage on the peddle?

jacko - 20/6/07 at 07:02 PM

Air in system ? try bleeding the brakes ?
Jacko

andrewturner - 20/6/07 at 07:21 PM

I have checked that twice

nitram38 - 20/6/07 at 07:57 PM

Check that the angle that your cylinder rods are being pushed is straight.
I found that at rest they were level on mine and went in at an angle under pressure. This caused me to have your problem.
I found that by moving the rod connection to my pedal by 5mm, that they started off at an angle and straightened up under pressure.
You may be suffering the same thing.

blakep82 - 20/6/07 at 09:13 PM

just a thought, are your calipers higher than the master cylinder? maybe needs a residual pressure valve (i think its called)

nitram38 - 20/6/07 at 09:17 PM

quote:
Originally posted by blakep82
just a thought, are your calipers higher than the master cylinder? maybe needs a residual pressure valve (i think its called)


Not required, calipers can be higher that the reseviour without any problems.

blakep82 - 20/6/07 at 09:55 PM

^ i've heard of times when the brack fluid can siphon back to the MC, causing the brake pads to retract too far. tends to happen on cars witht he MC lower than the calipers. just offered as a suggestion...

lsdweb - 20/6/07 at 10:22 PM

Have a look at A P Racing's tips on balance bar setups - here (PDF)

Wyn

britishtrident - 21/6/07 at 07:40 AM

What front calipers are you running ?

If Cortina/Escort it could be stuck piston.

RazMan - 21/6/07 at 10:02 AM

What method are you using to bleed the system? I have found that the Eezibleed doesn't work very well and leaves air in the system - there is no substitute for a good old fashioned jam jar and swmbo's foot

Fred W B - 21/6/07 at 11:16 AM

quote:

there is no substitute for a good old fashioned jam jar and swmbo's foot


You kinky b@stard you

cheers

Fred W B

[Edited on 21/6/07 by Fred W B]

nitram38 - 21/6/07 at 11:22 AM

quote:
Originally posted by Fred W B
quote:

there is no substitute for a good old fashioned jam jar and swmbo's foot


You kinky b@stard you

cheers

Fred W B

[Edited on 21/6/07 by Fred W B]


Yes, but you could be pumping forever and still not get anywhere

geoff shep - 21/6/07 at 03:48 PM

same question - what front calipers and have you got a picture of them.

andrewturner - 21/6/07 at 07:54 PM

At the rear I have GTI rear calipers and the fronts are a 4 pot set I made up my self after I was having the same problem with the cortina brakes.

geoff shep - 21/6/07 at 08:36 PM

Haven't played with a bias bar system but are you initially getting lots of travel in one circuit - rear by the sound of it - and then its better on further pumps? Can you isolate the circuits and test them independently? Could the offending callipers be upside down or somehow not have the bleed nipples at the top?

britishtrident - 21/6/07 at 09:38 PM

quote:
Originally posted by andrewturner
At the rear I have GTI rear calipers and the fronts are a 4 pot set I made up my self after I was having the same problem with the cortina brakes.


Q1 did you check the old calipers for a stuck piston.

Q2 Are the new calipers 100% true to the disc surface ---- if even at a very slight angle it will cause your symptoms.

You can check the master cylinder set up by removing the pipes at the master cylinder and screwing bleed nipples in.



[Edited on 21/6/07 by britishtrident]