2005 R1200GS ABS modulator failed

Hello all. I'm contemplating purchasing a gently used 05 R1200GS. The bike's been checked out by a reputable local shop specializing in BMWs and all is well save for the ABS modulator. The mechanic said if I don't want to go the expense of fixing/replacing it I could just ride it as is.

The fault that showed up stated: 'ABS motor rear defective'. The original owner has been riding it regularly, just without ABS.

So, according to the mechanic, who took the bike out for a good run, the 1150s have a different setup that result in only 60% braking (so-called residual braking) when the ABS fails. The 1200s revert to non-ABS too but with 100% braking. He has retrofitted a number of 1150s with a bi-pass kit from the UK but never for the 1200s because it isn't necessary.

Does anyone know whether NA '05 (and beyond) R1200GS's have the second generation ABS (iABS-2 system) or iABS-1 system?

Kevin

That model has an iABS (servo) system. A motor provides the hydraulic pressure, the brake pedal/lever controls the pressure through the modulator. The brakes are semi-linked - braking with the front applies some rear brake pressure as well, the rear pedal is rear brake only. When it's working, it's rather like having power brakes. One or two fingers on the lever will bring you to a rapid halt. In very hard stop the front lever alone will apply the rear brake hard enough to activate the ABS function. iABS-2 does not have the servo motor, but did not come out until 2007, and cannot be retrofitted.

My '06 RT has the same system and I like it, but my fingers are crossed that it does not fail. I've ridden the bike a couple times when it was not working by starting the bike and quickly riding off before the system initialized. Stopping required a LOT more force and lever travel before braking began, and I'm not sure if the front and rear brakes were still linked. I would not intentionally ride the bike without a working servo.

It's likely the previous owner sold the GS rather than pay for a new module ($2800+labor). ModuleMasters has supposedly been working to source rebuild parts, but the effort has been going on for a few years, and they keep pushing back the release date.

Personally, I'd walk away from this GS unless the total price of the bike and a proper repair (not a disabling) was substantially less than comparable models. Even if the local shop would bear the cost of the disabling, the lack of ABS will reduce your eventual resale value. There are just too many other options available.

lkraus said:

Personally, I'd walk away from this GS unless the total price of the bike and a proper repair (not a disabling) was substantially less than comparable models. Even if the local shop would bear the cost of the disabling, the lack of ABS will reduce your eventual resale value. There are just too many other options available.

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I completely agree. Why buy a broken bike when there are plenty of good unbroken ones available. Brakes working properly are a fairly significant safety issue. I would run away as fast as I could.

Thanks. I think I'll take your advice.

Kevin