1198S rear brake cylinder needs frequent bleeding

Hello again.
Does anyone else have issues with the rear brake pedal going soft & needing regular bleeding to get a decent pedal back?
There are no leaks internally or externally & no problems with the brakes linkage or adjustment. I don’t drag the brake with my foot, I only really use it when I’m stationary to stop the bike rolling if I’m parked on an incline.
Mark from M&M motorcycles & Performance Bikes told me that the heat from the engine boils/reduces the fluid’s efficiency due to the cylinder being bolted to the engine cases. Is this a common issue & if so has anyone modified the system (Shield?) to stop the heat affecting the brake fluid?

It’s just me then?
This is on the back boiler at the moment, the radiator has sprung a leak, another common issue it appears, as much as I love this bike, £650 for a replacement radiator :astonished: , someone’s having a laugh at my expense…

Sounds like you may have fluid leaking back past the seal, dont know if you can get a rebuild kit as Brembo are a bit funny that way!
Also they can be a bit of a pig to blead if they are the same as the 916 i.e. the nipple on the bottom?
The best way to do it is to take it off and turn it upside down put something inbetween the pads and then bleed all the air out.

As to the radiator get it repaired a few places on the net.

Hi Andy,

It isn’t just you chap it’s also a lot of owners…
There’s heat shield available in the States for some Ducati models with the rear M/cylinders stupidly attached to the rather hot crankcases.
It’s a well known problem on Ducati’s and modern MV’s with the M/cylinders fitted to the cases that the rear brakes are pants/useless.
However it might be worth trying race quality brake and clutch fluid as this has a much higher boiling point.

Steve R

Hi Steve.
Thanks for the reply, my mate with an Aprilia has a similar set up on his bike & he has the same problem.
Not sure if a shield will totally cure the over heating as the bolts might transmit the heat from the engine to the master cylinder. (Longer frequency between bleeding though?)
As for the radiator, all the repair is blocking/plugging off the leaking tube, it runs hot when stationary & lowering the cooling system’s efficiency isn’t going to improve this or something I want to do.
I have seen a larger capacity (race) radiator with better flow rates for (surprise, surprise) £650, someone’s done their homework…