2012 ec300 brake problem.

[nato]

I have been experiencing on the rear brakes that sometimes they work great and sometimes they wont even lock up! There is no leaks in the system and its full of fluid, Is there a chance it came from factory with an air bubble in the line? They are not cooking either as it was doing it from cold.

cheers nato.

[Jakobi]

Originally Posted by nato

I have been experiencing on the rear brakes that sometimes they work great and sometimes they wont even lock up! There is no leaks in the system and its full of fluid, Is there a chance it came from factory with an air bubble in the line? They are not cooking either as it was doing it from cold.

cheers nato.

Its very possibe Nato.. Have you tried reverse bleeding them?

[thumperrider1]

I've not had any problems on mine, but I also bled both front and back during my bike prep.

[nato]

Not just yet but i will when im home again next week. Will let ya know how i go.

[moto9]

It might be the line it's self, sometimes they get weakened and can expand or bulge under pressure.
And / or could be the master cylinder piston seals.

[Wimpy525]

Have not had any problems with mine. I though I bleed mine after every ride, this was the only way to keep brakes on the KTM. So far I have been impressed witht the brakes on the GasGas

[nato]

If there was a bubble wouldn't the pedal sink easy?

[300ec]

My rear brakes got the air within one or two weeks. bleeding does not help
found small patches of rust on the surface of the working cylinder - removed them. Now the brake in order

[boyscout]

Check to see if the rear pedal is bottoming out on the frame.

[GMP]

The brakes can be tough to bleed. Best way is first to remove the bleeder fitting and teflon tape the threads to seal from air. Get a big syringe or a vac pump and pull a HARD vacuum on that fitting. Open and close the fitting quickly. The flow transient will break any bubbles free. Repeat until what you draw out is air free. Don't forget to keep adding to the resevoir to avoid sucking more air in the system.