Bought one Today!! 1st BMW - 1st Brake Failure ;)

[santorini]

so i'm a pure BMW newbie after 10+years riding and having owned about 20 different motorbikes

2003 BMW r1100s in blue - I love it!! Great boxer punch and sound.. somewhat comfortable on long trips lol and nice solid feel and handling.

but the brakes failed!! When i test drove the bike this morning they were pretty firm and a bit grabby at low speed but I didn't think it was unusual.

Later cruising on the highway and went to brake and brakes suddenly very soft, I really had to muscle my hand closed and move the lever more than before.

Stopped for a break.. brakes firm again and very grabby (needing only slight pressure)… then super soft after a bit of driving.

Other clues? Bike apparently sat for at least 2 years. Was boost started yesterday with a weak battery. The flashing red "Brake failure" light is constantly on, as is the solid red warning light (triangle?) to the right of it.

I want to give more info on the bike and wait to post haha (I honestly don't know if has ABS or not.. :/) etc. but I'm coming down after a long exciting day (drove 250km) home on it and couldn't wait to ask you gurus

for oil change - any special ratchets or anything needed?

oh and any links to PDF files of the owner's or service manual??

[signit98]

It most likely has ABS and it most likely does not like the weak battery.
That is the first direction I'd look.
After 2 years of "resting", you may be well advised, just bleeding the whole system.
Oil change and everything else on this bike, is easy as can be.
Hammer and a wrench and you can fix 80% of the issues on that bike... if you have a real big hammer, you can fix everything!

[KMoore]

Put a new battery in and have the brakes bled. It probably has the servo assist abs brakes (does it make a whirring noise when pulling in the brake lever with the ignition on?) If I recall correctly, the warning lights come on if the battery is on the way out. If it does have abs and is the servo type, you can bleed them yourself, but it is a bit involved and I get the dealer to do it every two years as it is more than just bleeding the wheel circuit, the pump unit under the tank has to be bled as well. Hope it turns out to be a simple and cheap fix.

[KMoore]

Ha, I am a slow typer, Ralf beat me by a mile.

[1100s nut]

One way to test for servo brakes is turn key all the way clockwise "don't start" and grab some brake....if you hear the servos you have servo brakes. They are more difficult to bleed. But, like KMoore said its only needs to be serviced every two years. I might be wrong and probably am, but I don't think a weak battery will have any effect on the performance of the ABS as far as stopping power. Warning lights yes, and functionality yes. Congrats on the bike!

Lane

[Cruzer]

Agreed...doesn't like a weak battery. Undoubtably you have ABS.
Take off the tupperware. Only difficult part is to find the screw somewhere behind the badges on the inside. Sot of out of sight. Others come out in 2 minutes. Need to have most of the gas out of the tank, then lean it over to starboard (right side) on the piston which you will have covered with a towel. You must have that strange corkscrew brake funnel to fit in each of the servos, front and back to effect proper bleeding. Without it don't even bother. Fluid needs a pressure head. Pretty strait forward once you have a look. Or you can pay someone $110 per hour to do it for you.
Oddessey batery cheap and good. Will last for years and can charge well from almost a complete discharge.

Congratulations on the bike. Another love affair and about as expensive when you begin the farkling as most of have done. But much more fun than dinner and a movie.

Everyone's very pleased to help on the forum. Lots of knowledge and you can bet someone has already invented the wheel.

[santorini]

thanks for the replies guys! yah it must have the servo assist because when i pull the brake lever it does make that whirring noise.

weak battery definitely sounds like the issue - I will get a replacement today and hopefully my full braking power will come back!

it was definitely 'love at first sight' for this bike hehe I looked at a few dodgy ones first but then found this beauty.

[santorini]

battery question - will a 18aH battery be OK with the ABS ? how many amps do I need exactly? I don't wanna buy a new battery only to find its too 'weak' too lol

[Cruzer]

The ABS uses more power. Higher wattage alternator My battery is slightly below the required amperage rating, though still works fine.
Oddyssey recommends PC680. Think that's what I have but it's hidden from view now.
PC925 would be too big for the box and weighs another 10 lbs.

[ckcarr]

The PC680 is the Odyssey of choice for the R1100S if you go that route.

There was just a thread here a little while back regarding best price for one.
Where is the best place to buy Odyssey Batteries?

[santorini]

i live in Europe so not sure if they have Odyssey batteries…

[Cruzer]

Yup.
Search Odyssey Batteries Europe...Italy etc.

[santorini]

update - I still haven't had time to get a replacement battery but thought I would take the bike for a spin today…

bike cranked good and fired right up. Flashing 'brake failure' light and solid other warning light still on.

almost crashed!! After driving maybe 10minutes with 'normal' brake feel, I went to brake normally and the front brake pretty much locked up with very little pressure… Was super grabby and i rode home using just the rear brake

again - would this be the symptom of a weak battery???

seems odd that a weak battery would cause such odd and dangerous braking… :/

have any of you deleted your servo braking system completely?

[santorini]

also - where are the Brake fluid reservoirs on this bike? have searched but can't find . could low fuild cause this brake warning light to be on too?

[wiggledbits]

As others have wrote... at the least have the battery checked but if it is 5 or more years old replace it. Do a/ have a complete flush of the brake and clutch systems. I would also consider spending the money on new brake lines. The OEM lines have been know to deteriorate with time and long intervals with old fluid clogging the system with crap and I'm sure not doing anything good to the servo/ABS systems. Do it before you have an accident.

[Cruzer]

I second that last remark.
"Do it before you have an accident!"

[PFFOG]

Do some research, the lights and flash speed/sequence tell you what it is sensing as a fault.

As far as grabby, the servo brakes are very powerful, 2 fingers should be able to stand it on its nose. Many hated the servo system for this, personally I loved it! It is the one of the few things I miss from the S.

Agree a flush is a good idea, there is info on this forum on the procedure.

[santorini]

apparently its in 'residula braking' mode.

don't worry - i will do it before i have an accident

going to buy a new battery now.

my first encounter with this strange and wonderfullly complicated braking system

[brentw1]

check the brake switch adjustment, they should turn on the servo pumps before you actually
do any braking, so you have servo assist as soon as you begin to build hydraulic pressure,
if the switches turn on after you have begun building hydraulic pressure you will get a sudden
surge of braking when the pumps turn on. most dangerous, I find they work fine, I have them on
several bikes, as long as they are adjusted. they are not grabby just less pressure required to feather the brakes.
there are two switches one on the hand and one on the foot, you should hear the servos run
before there is any braking force.

[santorini]

good call brent! i checked today with the bike stationary and it seemed like the servo noise came on as the same time as the lever 'clicked' the brake switch.

I noticed a small screw on the lever near where it pushes in. is that the screw to adjust how it actuates the brake switch?

(got new battery now, going to pop that in the bike ! fingers crossed