back to my 1150 abs problem

[how much]

okee dokee!

i posted a problem a couple of weeks ago about a brake problem on my 03 1150GS (servo)

well i still have not sorted this and am at a total loss what to do next.

the problem:
the abs kicks in at really slow speed braking... ie the brakes are on-off at the final couple of mph to stop! its driving me crazy!

Steptoe suggested warped disks... and thats just what it feels like, the bike has only done 9000 miles

BUT!

turn the ABS "off" and the problem does not exist.... so it aint warped disks!

i have checked the gaps on the abs sensors to abs ring and both are within the specified range (mine are at 1.05mm)

the bikes just been in williams and been on the diagnostic for an hour or two for an unrelated electrical ignition fault. the mechanic couldn't really come up with any suggestions re the brakes

mine cannot surely be the only bike ever to show this problem?

any advice gratefully received



how much

no abs fault shows? all the dash displays are as they should be

 

[Tarka]

When is it happening......

Using front brakes only ??

Using back brake only ??

Using both at the same time ??

Every time you brake,or on a certain patch of road ?

Are the ABS rings totally clean with no damaged teeth ??

Are you braking in such a manner that you`re unloading the rear suspension and making the rear wheel
go light/lift?

Just some thinking material.....

Are you sure it`s the ABS kicking in....might it perhaps be a servo cutting out and you going on/off residual braking??

 

[forry]

When is it happening......

Using front brakes only ??

Using back brake only ??

Using both at the same time ??

Every time you brake,or on a certain patch of road ?

Are the ABS rings totally clean with no damaged teeth ??

Are you braking in such a manner that you`re unloading the rear suspension and making the rear wheel
go light/lift?

Just some thinking material.....

Are you sure it`s the ABS kicking in....might it perhaps be a servo cutting out and you going on/off residual braking??

I'd check the abs ring mine had one bent tooth and caused the same symptoms

 

[how much]

thanks for the tips..

its definately not the rear end going light, it happens as i gently reduce speed at say a junction, where i lightly brake with a view to maybe stopping or not! i.e. low speed/light brake application

its feels like the front brake going "on-off"

braking from speed or firm braking is fine

the servo seems to be making a lot of noises (they all do that sir.. i know)

seems like a front brake problem.... but i always brake with both

abs rings are spotless as is the whole bike they are the pressed stainless steel rings not the cast ones

like i said... abs switched off = no problem


could it be a faulty abs sensor? like i said tho the williams computer didnt pick any problem up

????????


how much

 

[Greg Masters]

Get a micrometer and measure the thickness of all discs at several points. Each disc should be a consistent thickness.

Get a dial gauge and measure the run-out of the rear disc as you rotate the wheel.

If it's OK, it's probably a software fault.

Greg

 

[forry]

thanks for the tips..

its definately not the rear end going light, it happens as i gently reduce speed at say a junction, where i lightly brake with a view to maybe stopping or not! i.e. low speed/light brake application

its feels like the front brake going "on-off"

braking from speed or firm braking is fine

the servo seems to be making a lot of noises (they all do that sir.. i know)

seems like a front brake problem.... but i always brake with both

abs rings are spotless as is the whole bike they are the pressed stainless steel rings not the cast ones

like i said... abs switched off = no problem


could it be a faulty abs sensor? like i said tho the williams computer didnt pick any problem up

????????


how much

Check the pressed steel abs rings again .I had one tooth bent you could hardly notice ,everytime the sensor passed it it thought you were slowing down and the servo made a noise.

 

[Camo Jo]

maybe also check the switch on the brake lever.

I know when these bikes fall over and the hand guard press against the brake lever, (activating the switch) The ABS won't activate.

The switch may be very sensitive / loose and when braking lightly may affect the abs.

Worth a try and easy to check.

Good Luck

 

[how much]

I'd check the abs ring mine had one bent tooth and caused the same symptoms

ok

had another really close look tonight.....

one bent tooth on the front abs ring


how the hell did i miss it first time... it was bent away from the sensor at least doubling the "gap" it should be (bear in mind mine are at the high end of the allowable range without any shims fitted 1.05mm)

if your right that should be my abs problem sorted

cant get out to check it till later in the week bike is in bits again so will post an update as soon as i can ride it!



how much

 

[how much]

Problem sorted

yup

one tiny little bent tooth... bent back around 1mm


brakes/abs now works fine


makes a change to have such a cheap fix



thanks

How much

 

[forry]

yup

one tiny little bent tooth... bent back around 1mm


brakes/abs now works fine


makes a change to have such a cheap fix



thanks

How much

Glad it worked

 

[how much]

cant believe such a small amount of damage to something as exposed as the abs ring could cause so many problems!

i had to literally check the teeth "one tooth at a time" and the deflection was so small i nearly missed it again! the deflection was approx the thickness of a tooth

and that was enough!

rode the bike tonight.... puuuurrrrrrfect brakes


thanks again to everyone for their input


this forum is GGRRREEAAAAAT

 

[blues n twos]

Great story and typical of the members on here to hit the nail on the head

Pleased it has all worked out for ya

Jon