Advice needed please..servo noise

[(RIP) Bobble]

Could do with some help please

I've got a problem with my "03" 1150 GS abs 35k miles .... when I put a little pressure on my rear brake lever I get the normal servo sound, however if I push the lever further down the noise becomes much deeper and louder (more so than usual) and it sounds as thought there is air in the servo, I've also noticed that if I'm slowing down (10mph) I can sort of feel it in my foot and the sound is more like a metal grateing noise as if the pads are down to the metal. I changed the pads about a month ago and yesterday I took the caliper off and checked everything and all seems ok. The outside pad looks almost new and the inside pad looks 3/4 new. The abs warning lights have never come on whilst riding, oh and I ride about 1k per month so they get used a far bit

Could it be air in the servo? I have noticed my brake fluid is now below the low mark. Could air get in the servo even though there is fluid in the reservoir? I've never had to top it up before. Oh and I hate to say it but in the 21 months I've had the bike the fluid has never been changed

 

[Fanum]

I think you've answered your own question there haven't you

Top the fluid up quick for one thing........if it hasn't got air in now, it will have soon if you're running with low levels

I don't know if the noise you describe is a symptom of air in the servo TBH......St. Eptoe may be along to pass comment on that, but IIWY I'd get on with changing the fluid....Neil did a thread on it a while back and I've seen him do it on my Adv...it's nowhere near as complicated as BMW make it sound and it only took him 10 mins to do front and back on mine- find the thread, grab a bottle of fluid and get on with it!!

(if the noise stops, it's job done...otherwise you can carry on looking for a solution! )


PS FWIW I think the schedule says the fluid should be changed and bled every two years but I may be wrong on that.

 

[(RIP) Bobble]

Thanks for the reply.... I shall be getting some fluid at lunchtime, but I don't think it will make much difference as it's only just below the low level (I hope to stand corrected). I'll now go and search the forums for Steptoe's thread, I looked last night but never came across it, I must try harder

 

[(RIP) Bobble]

No.. not the fluid level, I actually put the bike on level ground and the fluid was just above the minimum... back to searching the forum for Steptoe's thread

 

[Steptoe]

No.. not the fluid level, I actually put the bike on level ground and the fluid was just above the minimum...

Check the level in the servo unit reservoirs under the tank .

 

[(RIP) Bobble]

Check the level in the servo unit reservoirs under the tank .

Thanks.. I'll have a look tonight.