RE: R1100 RS revisit and diagnosis

["Minor, Bob" <Bminor@xxxxxxxx>]

Wow, I've been reading these lists for a long time and they only other engine failure of this magnitude that I've heard of was the late/great Lentini's bike that fried at around 70,000 miles.  What needs to be remembered about Lentini's though is that his bike was probably the most experimented and tweaked machine held by a private individual.  His assessment placed blame on his use of mid grade gasoline instead of premium.  He figured he probably had mild detonation going on for a long time that eventually did the damage.  I believe he too lost the pistons and valves.

I bet there are a lot more wrecked bikes out there than blown motors.  There should be plenty of used engine parts available from the used parts vendors.  I can't imagine what the parts would cost new, but I bet it's close to the price of a good used motor.  It sounds like you need barrels, pistons and heads.  They must be available used at a fraction of the new price.  The funny thing about used parts is that the less the original part fails, the cheaper it is used. It's that supply and demand thing. 

Bob Minor
'96 R11RS
'97 F650ST

   

- -----Original Message-----
From: owner-oilheads@xxxxxxxxx [mailto:owner-oilheads@xxxxxxxxx]On
Behalf Of rob
Sent: Friday, October 08, 2004 5:14 PM
To: oilheads@xxxxxxxxx
Subject: R1100 RS revisit and diagnosis


Hi all,


Well, I finally cooled off enough to take my RS out from
time out mode and diagnose what was wrong with it. It had started
to run on one cylinder about a hundred miles from home. Rode
home, ignored bike. Well...

Checked spark, fine in both cylinders, so decided dealer had
better diagnostics. Result? Not Good...in the suspected "dead'
cylinder, 100% leakage. Yikes. In GOOD cylinder, 80% leakage!!
double yikes. Right side(dead) had a slice o' pie shaped chunk missing
and unaccounted for. No sign that it'd hit the piston or cylinder wall.
Both exhaust valves burned.

All this on a bike that's been meticulously maintained, for both
service and fluid intervals. What's particularly scary is that the
leakage had gone from under 10% to failure in 14k miles, bike has 44k
now. The wrenches guess is a combo of California gas as well as poor
metallurgy. When I asked about this, I was told it's not uncommon;
the 1100 RT's had some history , but never an RS. The 1150's, quite a 
bit more common.
Triple yikes! So, think I'll fix it (don't ask what they'll charge), 
but not
sure if I'll keep it. This has been the most capable BMW I've ever had 
in terms
of being flexible to do the things I want a bike to do. But...after 5 
tranny replacements,
all at BMW's expense, a sight glass blowing out and stranding me, fuel 
pump failing and
stranding me, and now this, I'm a weeee bit nervous. Damn. Sigh.

Thanks to all who responded originally!!


Rob

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