Starting problem

[Mark Easterbrook <mark@xxxxxxxxxxxxxxxxxx>]

I had strange problem this weekend with my 2000 R1100RT.
It had not been run for a couple of months (I have been
using my airhead for commuting because it is easier to
get through heavy traffic). I gave it a clean and wash
down, but only with a low power hose. The battery was
a little low.
Initially it started but stopped after a few rotations,
and then would not restart - the engine turned but
would not fire. As the battery was low I charged it
for an hour (~2 amps) and tried again. The engine
turned over but would not fire - there was plenty
of power in the battery to spin the engine but it
was not firing.
I suspected the battery might still be low so I left
it on charge for about 5 hours, the charger started
at ~2 amps and dropped to less than 1 amp.
I tried again but it still just spins the engine
without starting - however, it did seem to fire just
once so I started experimenting.
With the fast idle closed - nothing, half (latch
position - nothing, fully open - nothing).
Then I opened the throttle while it was turning
and it fired once, so I kept turning with the thottle
open and it eventually started and was quite happy
to tickover.
I took it for a few km ride to warm it up and it ran
perfectly.
A day later it started up without any problem.
(Daytime temperature here is in the 15-20 range at
the moment and mostly dry).

Has anybody had anything similar. I doubt it was
water because it has been driven through some very
wet conditions on a number of occasions and not missed
a beat. My guess is the fuel injection system
got confused by the low voltage and a fully open
throttle somehow reset it.

I know the ABS does not like low voltage, but I can
do without it, but the other electronics are a bit
more important - is it time to for a new battery.
I know from experience that the airhead batteries
start to fade after about 5 years, so I guess the
oilheads might suffer the same.
Is it worth replacing with one of the new gel batteries?

- -- 
Mark Easterbrook CEng MBCS CITP
ACCU for professional software developers.
Open Source as an alternative to you-know-who.
BMW motorcycles for transport.

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