R1200 GS LC - spongy feel front brake lever

[capers1962]

Hi,

My bike has a spongy feel to the front brake.
The Brembo's work well to slow / stop the bike, but the feel is spongy.
I am told that this is not uncommon.
I have spoken to a couple of people who have mentioned that there is a video about this, but I'll be jiggered if I can find it.
Apparently, it is something to do with the length of piston travel in the front master cylinder and there is a fix to reduce the length of travel (or something like that) that does not affect the efficiency of the brakes.

Has anyone else had this?
Can anyone point me in the direction of 'said' video, please?

Thanks in advance.

 

[DJ123]

I'd bleed them out, replace the fluid and then see how you get on. I can't say i've had that feeling on mine in the last 18 months/26K miles at all.

 

[capers1962]

I have bled the brakes and done the ABS pump flush, which made no difference.
IIFC, it was something to do with adjusting the length of the plunger stroke, but I may be mistaken .....

 

[Orbit]

There is a very small Grubb screw which needs to be released slightly maybe 2mm and then the main plunger can be adjusted however you need to be very careful that you don't over do it! Literally a couple of turns or less. Too much and you risk the brake coming on. I found a video a while ago which demonstrates adjustment to the clutch lever in the same way.

 

[Orbit]

Have a look at this albeit clutch side

 

[capers1962]

Thanks @Orbit that looks very similar to what I remember.

Ta muchly.

 

[Schtum]

Have a look at this albeit clutch side

I have it on good authority that's the one that BMW tell their techs not to touch. As you suggest, it's a very find adjustment. On the clutch is takes very little to change it from dragging to slipping.

However, if you get it right, it can turn the worst, clunky LC gearbox into something of which Suzuki would be proud. Well, at least until the oil heats up....

 

[Teeonethousand]

I have just been through this and what worked for me eventually was bleeding the front brakes with a vacuum pump by sucking the fluid out rather than pumping lever. I tried everything else, bled several times, activated pump via my motoscan, did it again, and again, tied lever to bar for a week etc etc.

IMHO fiddling with the Allen screw on the brake lever plunger is not the answer.…but bloody hell it was frustrating. Mine is as it should be now.

 

[kennyc]

I find it strange if the techs are told to not touch

I have it on good authority that's the one that BMW tell their techs not to touch. As you suggest, it's a very find adjustment. On the clutch is takes very little to change it from dragging to slipping.

However, if you get it right, it can turn the worst, clunky LC gearbox into something of which Suzuki would be proud. Well, at least until the oil heats up....

this adjustment, as anyone who has changed the original levers will have found out, you transfer the actuator rod over to the new lever, the adjustment allows you to take the initial play out of the system, and if you cant do that without risking slippage then I would suggest you shouldnt be working on the bike in the first place