[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: R1100s - wandering idle speed (2)


Good comments - thanks.

The throttle bodies (TB) were completely rebuilt units - new shafts,
bearings etc.  The sheathes the Bowden cables roll over are all squeaky
clean - but either way, this issue of wandering idle speed occurs only
when at "idle".  Both the LH & RH TB shafts that the Bowden cables
attach to are sitting firmly against their respective stops, so there's
no issue here.

Will try graphite when the occasion arises ....

If I keep engine revs consistently below 4000 to 4500 rpm, oil use is
negligible.  OTOH, if I let the engine know who's the boss around 7000
rpm, oil usage is "noticeably" below the sight mark after a week but
requires minimal topup oil.

Unfortunately, I have to defer to the "expert barbarians" as this is my
only method of getting to work etc.  It's a $150 cab fare to/from work -
or the nearest BMW dealership for parts needed to get the bike working
again if weekend repairs are undertaken.  I guess I should consider
buying a $500 "hack" for these occasions !

I'm moving to Canberra (3.5 hrs drive south-west of Sydney) in a couple
of weeks time so will have to find another expert "barbarian" ... will
consider an alternative as suggested !

So - what could be the cause of this pesky wandering idle ??

Sydney - soon to be Canberra
-----Original Message-----
From: Robert Silas [mailto:robert.silas@xxxxxxxxxxxx] 
Sent: Sunday, 6 May 2012 10:04 PM
To: Kit Scally; oilheads@xxxxxxxxx
Subject: Re: R1100s - wandering idle speed

The basic problem is to let the "expert barbarians" touch the bike.
Check if bottom of sheaves, under the cable, might accumulated dirt,
real solidified dirt, so the cable does not roll on a constant diameter.
"Had my favourite BWM dealer install 2 refurbished throttle bodies" ,
what does it mean refurbished?? cleaned??? or new shafts.. 

I have only 175,000 km on the clock,(does not use oil btwn changes),
never a problem except once dirt had to be cleaned under the throttle
cable. Do not oil the shaft much, rather use graphite lube, because oil
picks up dust. (In Australia there could be more dust than in Canada???)
I was over there 3 times but in winter times.

In any case it is a good idea to take the filter outside of the tank, I
had problem with that within the first 15,000 km. Mine is a 1994
R1100RS. If your bike is pulling to the right see
www.robertsilas.com for my remedy.

Find a better mechanic, these are really terrific life-time bikes. 
Bob in Montreal.

----- Original Message ----- 
From: Kit Scally 
To: oilheads@xxxxxxxxx 
Sent: Saturday, May 05, 2012 8:44 PM
Subject: R1100s - wandering idle speed

Hi to the Group,

First, apologies for this war story being told in kms rather than miles.
50 miles = 80 kms. My 1999 1100s now has 207,000 kms on the clock and
still going strong.  My daily commute is 100kms, averaging 550kms per
week and ridden "firmly-plus" rather than pussy-ing along.

Had my favourite BWM dealer install 2 refurbished throttle bodies a
month or so ago because of general wear (rattle) and idle speed
increasing with engine temperature from 1100 (cold) to 1450 or so (hot).

The LH replacement body (the one with the throttle sensor pot) shaft
seized at 75% throttle during a 300kms drive a week or so later.
Managed to drive 40 kms in 3rd gear to the next petrol station to look
into the problem.  Shaft was stuck as "tight-as" !  Squirted heaps of
WD-40 in the general direction of the inside LHS shaft before it
eventually freed up enough to drive the remaining 150kms home.

Took bike back to shop and NFF for the shaft sticking. Bugger!  (Side
issue - petrol tank managed to get a gob-full of water in it after shop
washed-hosed bike down to clean it.  Power response vvs throttle opening
was now interesting ...)

After this, idle speed wandered all over the place - hot or cold.  Took
bike back to shop - this time, LH "rubber gland" joining throttle body
to engine body diagnosed as leaky (could be seen visually).  Both LH &
RH gland replaced. Idle speed now fairly constant long-term whether cold
(1100) or hot (1200). However, the idle speed wanders all over the place
over "seconds" hot or cold -  idles averages 1150 then rises to
1250/1300 in 2-3 seconds - holds - then down to 1100-1050 for 3-5
seconds - holds - then up again etc etc.  (The variations are a "tacho
pointer width" or more.)

1)  Idle issue - What's the likely culprit ?  I don't have access to my
TwinMax right now.  What should I be looking for or replace ? 
2)  Water issue - Put a cupful of Methylated spirits into the fuel tank
to try and soak up the water but not entirely successful, particularly
when the low fuel LED comes on.  What now ? Drain the tank & replace the
fuel filter ?  (Aarrrggghhh !  both nasty jobs.)

As a complete side issue, since all this has been going on the bikes
roll-on torque has increased noticeably ....

Many thanks - all ideas gratefully accepted.

R1100s Mandarin