2004 R1100S BCR power loss and lumpy at higher revs

[masha]

I've had my 2004 BCR since 2007 and its been faultless (except battery letting me down once - and it appears to be a bike that won't run with a dead battery for long regardless how you start it), serviced annually regardless of miles - which isn't usually much as I am fortunate enough to have other bikes. Standard spec except a y-pipe, tail tidy, and few extra carbon panels.

I'm having the codes read next week and will book in for service and MOT wit Jim Cray as usual there after, but bike was lumpy last weekend on about its 3rd trip out this spring. Any pointers appreciated (I will get the fuel filter, plugs, valve clearances, oils and filters done this time around along with anything thrown up by code reader of course) Fingers crossed its okay for another year, as its very low mileage bike (probably too low, I should get out more) and always stored on a paddock stand before the engine is switched off after a ride (as no centre stand on BCR due to fairing).

[The Teutonic Tangerine]

Mouse next in the Air Box restricting airflow.

[masha]

anything's possible - its been in storage and something is throttling combustion - I will check for vermin, frogs, leaves etc. It will be interesting to see if something along the lines of a throttle position sensor is playing up for example - I've had that on my 4-stroke scooter recently with similar effect. Thanks, any all suggestions appreciated

[Boxadog 2000]

Could be

Old fuel
Coil pack when hot
Throttle body ballance

[nab 301]

As above , assuming it's a twin spark , a stick coil on the way out.

[masha]

thanks yes, could be any of those I guess. Yes its a twin spark.

[Tapio]

I have an intermittent starting problem with my BCR ’04. From searching the net on what the problem might be, I’ve found out that it’s fairly common that the stick coils fail.
Since they’re not a passive component, but an active, they cannot be checked with a multimeter. Only thing you can do is replace them with ones that you know are ok, and see if the problem disappears.

Indications on a stick coil about to go south:
Problem occurs mostly when engine is really hot
Problem occurs on high revs

[masha]

Yes it could well be the stick coils, any idea roughly how much they are as a replacement part for the twin spark 1100S boxer?

I have a friend with his boxer911 diagnostic tool visiting in the next couple of days to see if there is anything detected on the diagnostic, recorded on the ECU and after that I will get the coils checked/replace when it goes in for oil/filter change and MOT next week.

[dave the german]

£81 + VAT from my local dealer - just had to replace one on mine - probably going to replace t'other on recommendation of local mechanic (he has no ties to the dealer so nowt in it for him) What do the collective think?

[ned1]

Replaced one coil stick on my old 2003 twin spark which was playing up by a (very good) independent,
he never said that you should replace both.

Ned

[masha]

no, that's fair enough - one either fails or it doesn't - 2nd one could go on for tens of thousands of miles more, so why replace both, just the failed one (at that price too)

[masha]

Tapio - that sounds like my symptoms - so still basing it on stick coil most likely - certainly worse when the bike warms up and at higher revs.

I plugged into a friend's GS911 diagnostics tool today - and the only error we couldn't clear was "throttle idle switch = on" - so I'm wondering now if there is a micro-switch somewhere in the fast-idle enclosure that has failed?

Other than that I'll give it a full service fluids and filters, and get it checked over (even though its only done about 100miles since the last one).

Does anyone know of where I can get a spare used Throttle Position Sensor to try - MotoBins?

[tanneman]

or http://www.motorworks.co.uk/vlive/Home/index.php

[Tapio]

I plugged into a friend's GS911 diagnostics tool today - and the only error we couldn't clear was "throttle idle switch = on" - so I'm wondering now if there is a micro-switch somewhere in the fast-idle enclosure that has failed?

This is getting more and more strange. First the smudgers recommendations, and now this…

There’s a black box thingy that sits underneath the fuel tank, in the front. Four cables go to it.
1 left cyl throttle
2 right cyl throttle
3 your right grip
4 fast idle switch
There’s no micro switch in that thing. And there’s no micro switch in the fast idle switch either.
There are no micro switches anywhere in the system!

I’m telling you: the Boscht motronic system has no way of telling if you have engaged the fast idle or not. It must mean something else.

[Tapio]

Took a picture of it today. No electrical stuff in here. Cable at red arrow is the choke. When you pull the choke lever, the cable turns the grey disc, to open the butterflies a little bit. That’s all that happens. No signal for the Motronic for a cold start enrichment.