Rear Brake on a Senna : LUSENET : MV Agusta F4 : One Thread

Has anyone out there had problems with their rear brake keep getting air in the system - so losing the brake completely? My Senna has been back once already for this and has now done it again. Any ideas?

-- Nick Dickens (, November 20, 2002


at least on the 2002's...

1. The reservoir is very small 2. The reservoir is very close to the exhaust (even with the sheild) 3. Standard DOT 4 and 5 fluids do not stand up to high temps very well 3. Refill with highest temp brake fluid you can find. (Mutol...)

Keep a check on the pedal and grip. Bleed and refresh as needed.

You could experiment with an insulating pipe wrap or "other" fixes for the heat. That will be my next step in solving a similar problem if the high temp brake fluid does not do the trick.

Good Roads, Ride Well,

Scot/NC '02 Silver Monoposto

-- Scot Hennon (, November 20, 2002.

You'll find that almost everyone has this problem, and I'm probably one of the loudest to complain about it.

My rear brake hasn't worked for a while now, since the dealer completely flushed it and put in new fluid. Now my front brakes are giving me a little trouble (mostly on the track) so I'm going to have them flush and put in Motul race fluid. I have also wrapped the headers with thermal wrap, which possibly is making the pipe hotter near the resivoir now, however I plan to wrap the pipe there too (when I get more of those damn stainless zip ties).

-- Andy Ruhl (, November 20, 2002.

I lost the use of the rear break on my senna after 1300mls during a hard run. This was effectively cured by ditching the fluid and replacing with a race spec equivelant. Tony B

-- Tony Beckwith (, November 21, 2002.

I have had my Senna since May and have not had any brake problems. A fork seal and water pump have been replaced, other than that, nothing.

-- greg petersen (, December 09, 2002.

After 8000 miles, up-grading to Dot 5 fluid, and having bled the brakes numerous times, the master cylinder has just been replaced under warranty - look how close it is to the exhaust and it's easy to appreciate why it constantly boils and eventually cooks the seals.

When I eventually get the bike back (yawn!), I'll be putting some exhaust wrap around just that section of the exhaust. Demon Tweaks sell it in 50 metre rolls plus the stainless cable ties. According to an anonymous (!) source at Three Cross, this is a common fix.

-- Ralph (, December 10, 2002.

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