04 Running very lumpy

[jtw000]

I've had my 04 now for a few months and lately have noticed a drop off in economy and it seems to run poorly at tickover running from just under 1000rpm to suddenly dropping to 500 and then spiking higher. It's difficult to tell if the problem persists through higher revs. Also I filled her up last night and then pressed the starter button and the engine turned but failed to fire. I turned off the ignition and back on and then it fired straight away. I'm thinking this sounds like the injectors need cleaning but is this normal behaviour for these or is it a common fault showing its head?

 

[GSmonkey]

When was it last serviced? Rough running could be something as simple as throttle bodies need syncing.

 

[Engineer]

I've had my 04 now for a few months and lately have noticed a drop off in economy and it seems to run poorly at tickover running from just under 1000rpm to suddenly dropping to 500 and then spiking higher. It's difficult to tell if the problem persists through higher revs. Also I filled her up last night and then pressed the starter button and the engine turned but failed to fire. I turned off the ignition and back on and then it fired straight away. I'm thinking this sounds like the injectors need cleaning but is this normal behaviour for these or is it a common fault showing its head?

My plugs were shot - hadn't been in that long; according to my dealer I had the old type fitted? (2005 1200GS)

Either way, 4 new plugs changed everything and it has been running really smooth for the last 5,000 miles, in fact smoother than it has ever been.

 

[jtw000]

She was only serviced just under 6 months ago. I did change the plugs and oil myself when i got it for 20/50 mineral and 4 new plugs which I ordered from ebay. They were different from the ones in it and made her run like a sack of crap for the three days i ran her with them in before putting back the originals. The lumpiness has come on fairly recently but to be honest, i'm still a bit over-cautious of the bike after reading all the horror stories on here and if i had any other bike running like this I wouldn't worry. I have to admit I bought this expecting bullet-proof reliability but the stories on here make them sound worse than Ducatis.

 

[gavin@iow]

She was only serviced just under 6 months ago. I did change the plugs and oil myself when i got it for 20/50 mineral and 4 new plugs which I ordered from ebay. They were different from the ones in it and made her run like a sack of crap for the three days i ran her with them in before putting back the originals. The lumpiness has come on fairly recently but to be honest, i'm still a bit over-cautious of the bike after reading all the horror stories on here and if i had any other bike running like this I wouldn't worry. I have to admit I bought this expecting bullet-proof reliability but the stories on here make them sound worse than Ducatis.

Have you tried a TPS reset?, worth a try.

 

[2 wheel humvee]

and 4 new plugs which I ordered from ebay. They were different from the ones in it and made her run like a sack of crap for the three days i ran her with them in before putting back the originals.

Are you saying you put the used plugs back in ? The same plugs that you had saw fit to change at the last service you carried out?
Try fresh plugs and get the throttle bodies balanced

 

[ianm00]

I had a faulty o2 (lamba) sensor (on the exhaust) that gave the same symptons as your bike. Mine was under warrentee so BMW computer at the dealer identified the fault and they replaced the part.

Ian