Formula Oro K24 lever not releasing fully

AlunR

Hi, I have Formula Oro K24s fitted to my bike (OEM). The bike was new about a year ago (July 2007) and at the time the brakes were excellent. After a period of 6 months or so first the front brake and then the rear brake levers stopped returning fully causing the pads to drag. I bled the brakes which seemed to cure the problem. However the rear lever has again stopped returning fully. I have bled the system again but with no joy. Where the lever stops there feels to be a slight restriction in the travel. A light push with the finger helps it return home but it is becoming a real pain. The braking power still seems very good its just the lever is not returning fully when released. Any thoughts?

nicklouse

when you first bled the brakes was the fluid in the master reservoir (lever) milky?

there is a know issue with some assemblies. contact the supplier for arranging the warrenty replacement of the main piston.

AlunR

Funnily enough it was. I just put this down to different fluid types. I will contact the suppliers and see what they say. thanks for your help.

nicklouse

AlunR wrote:

Funnily enough it was. I just put this down to different fluid types. I will contact the suppliers and see what they say. thanks for your help.

what do you mean by different types of fluid?

AlunR

I used a DOT 5.1 grade of fluid when I bled the brakes. DOT5.1 is a Glycol based flluid same as DOT 3 and DOT 4 but with additives to help it perform better at higher temperatures. I thought it reasonable to expect a difference in appearance between the old and new fluids (brakes originally had DOT 4) though was a bit surprised to see how cloudy the old stuff was.
Do you think using DOT5.1 could cause a problem?

nicklouse

nope, the cloudy fluid is the sign that the mater piston is at fault.

warrenty replacement.