Stegy

Hy,
I've searched the whole forum about magura tips, but nothing helps.

Here is my problem.

On my FG F1 comp I have Magura hydros (first version), and I'm having trouble getting them to work properly.
Rear brakes lock up wheels after 3 or 4 servo movements (pumping), but fronts are the problem.

I've seen that piston in front main cylinder isn't moving out like the one on rear's main cylinder.

I've tried bleeding them from master to calipers, no bubbles, but when I add about 1-2cc pressure in main, piston moves out and slightly blocks front wheels while servo is in neutral position, tried to release little oil from calipers, but then I get less braking power.

Further, servo moves about 30°, while servo for rear pulls out the piston in full lenght. Both servos are Hitec 5945, but if I move front brakes servo by hand little further, front wheels are blocked the way they should be.
I dont believe that this servo is too weak for hydros.

I've checked, no leaks anywhere, just dont know what else to try, and next race is coming quickly.

Any tipe of help and tips would be very appriciated.

J_D

ur pistons may have seized, u can unseize them, i just dont know how

caad5

Pistons may be seized as JD has mentioned or it sounds like your End point adjustment is not correct.

Stegy

End points are setup correctly, when I remove servo arm from main cylinders shaft, servo moves its full travel, and it inst servo problem , it has enough power ( 13kg).

caad5

oh yes i never said it didnt have enough power the 5945 MG has plenty. Well then check your pistons on the calipers and make sure they are moving freely and fully in and out. It still sounds like there is not correct travel when the servo arm is attached to the master cylinder rod or there is still air in the lines/master cylinder reservior. Are these brakes brand new or you have used them for a while ? Because if they are new Magura's can require a lot of bedding in before they start working correctly and to their maximum braking. You have to be on an off the brake a fair bit during the bedding in process.

Stegy

They've been through 5-6 race meetings, so I can say they are "break-in".

caad5

The only other thing i can think of without seeing it is that your master cylinder is losing pressure somehow. As a test swap the rear master cylinder to the front and then test front braking through servo. If it works correctly then you know its a master cylinder fault.