BMW R1100S Subframe Weakness Problems?

On the weekend, on our way back from Merimbula, heading into Orbost on
the Dalgetty road from Bombala, a mate's BMW R1100S suffered what could
be mildy described as a major structural failure.

He was braking for a tight left hander and setting himself up nicely for
it, when suddenly the bike propped upright and after much washing off of
speed, he clouted the earthen bank on the other side of the road.

It was discovered that the subframe that holds the seat, exhaust, rear
cowl, etc had sheared off at its two mounting points. Further, the right
rocker cover was damaged as it "oggy knobbed" its way into the dirt on
the bank. No other damage occured. In fact, other than the oil leak,
you'd swear that there was nothing wrong with the bike, until you
wobbled the seat, that is.

Had the exhaust not have been bolted to the rear sub-frame, then the
whole kit and kaboodle (no, not knobdoodle) would have separated from
the bike, with consequentially disasterous results.

The bike was able to be jerry rigged with a light chain and turnbuckle
to support the rear of the frame and a bit of exhaust putty and mastick
sealed, more or less, the leaking rocker cover. He was able to ride it
home to a mate's place, where he was to organise transport back to BMW
in Melbourne (he lives in northern Vic).

We think that when the frame broke, he more or less lost control of the
bike, but somehow managed to slow it enough before running off the road.

The only load on the bike was himself (around 95 kilos) and his gearsack
rack and bag, which weigh bugger all, really. Certainly it's nowhere
near as much as what a pillion would, and two panniers filled with
clothing for said pillion and rider, which is what the bike's designed
to be fitted with (the gearsack rack was fitted by the Beemer dealer
before he tookd delivery of the bike).

I'm just wondering if any of you guys have heard of this happening
before.

It'll be interesting to see what BMW does about it. I think that the
bike's still under warranty. Even if it's not, it indicates that there
may be a serious design flaw, something for which BMW isn't exactly
renowned for.

 

I owned a 1998 model R1100S and had no problems with the sub frame despite
competitive touring with panniers and tent etc, did the failure occur in the
alloy brackets welded to the main frame or within the subframe itself? I am
aware of a number of failures where the welded on alloy tabs that mount the
steel rear subframe brake off during a collision or accident, many of these
are repaired by re-welding.

Keep us imformed.

Boxer

 

You haven't seen The Long Way Round, have you?

The same thing happened to one of their BMWs...

big

 

@yahoo.com.au:
[...]

Am I the only one that got this far in to the story and
thought "Where was Maggie during all of this?"?

GB

 

Just finished watching that episode in fact ;-)

 

Just keep maggie away from it, she's known to bend subframes.

 

I think it happened to 2 of the 3 R1150GS's, although in each case, only
on one side.

David

 

Where the subframe connects to the main frame.

 

Moto 1 currently has the bike. BMW suggests that the sub-frame is good
for 200 kilos. I'm not sure where it's headed. I think the mate has
submitted an insurance claim. So, it's probably up to the insurer and
BMW as to how they can negotiate a settlement.