Help diagnose R12GSA oddness

[drsylvester]

Hi all, was hoping some of you guys could advise me with regard to (what is to me) odd engine behaviour on my 1200GSA, bought from Balderstones in Peterborough last year (07 model). This is my first BMW and boxer configuration engine so wanted to sanity check my (potentially dumb) question before calling the dealer.

I've now done around 3500 miles but about 500 miles ago after a ride home from work, I stopped on the drive with the engine running and immediately noticed that it was idling very 'lumpy' - almost as if it wanted to stall but would run again just before doing so, making the bike shake left to right much more noticably than normal. Don't get me wrong, it never actually stalls and always starts just fine. I also noticed on the morning afters ride to work that engine braking seems to be quite 'severe' now too and my usual average 49.4 mpg to and from work has dropped to around 44 mpg. Riding in slow traffic is also much more difficult as trying to hold around 1500 rpm in 1st gear seems impossible.

I have checked the colour of all 4 spark plugs and they are a nice tan colour (all 4 are the same colour too) so it doesn't seem to be misfiring but I am far from competent in this regard. And it only seems to exhibit this behaviour once it has warmed up.

What do you guys think? Is it normal boxer character that happens as they become more run in, or is it symptematic of a fault somewhere? I know I should probably just phone Balderstones but I don't want to appear like a complete tw*t who is just paranoid over his beloved, so I thought I'd run it past you guys first.

Thanks in advance.
Derek.

 

[Engineer]

Hi all, was hoping some of you guys could advise me with regard to (what is to me) odd engine behaviour on my 1200GSA, bought from Balderstones in Peterborough last year (07 model). This is my first BMW and boxer configuration engine so wanted to sanity check my (potentially dumb) question before calling the dealer.

I've now done around 3500 miles but about 500 miles ago after a ride home from work, I stopped on the drive with the engine running and immediately noticed that it was idling very 'lumpy' - almost as if it wanted to stall but would run again just before doing so, making the bike shake left to right much more noticably than normal. Don't get me wrong, it never actually stalls and always starts just fine. I also noticed on the morning afters ride to work that engine braking seems to be quite 'severe' now too and my usual average 49.4 mpg to and from work has dropped to around 44 mpg. Riding in slow traffic is also much more difficult as trying to hold around 1500 rpm in 1st gear seems impossible.

I have checked the colour of all 4 spark plugs and they are a nice tan colour (all 4 are the same colour too) so it doesn't seem to be misfiring but I am far from competent in this regard. And it only seems to exhibit this behaviour once it has warmed up.

What do you guys think? Is it normal boxer character that happens as they become more run in, or is it symptematic of a fault somewhere? I know I should probably just phone Balderstones but I don't want to appear like a complete tw*t who is just paranoid over his beloved, so I thought I'd run it past you guys first.

Thanks in advance.
Derek.

Sounds as though the idle is a bit lumpier that it should be.
There is normally loads of engine braking on these bikes so hard to say if yours is different.
Get Balderston to take a look at it - I'm sure they won't mind, they are normally very helpful

 

[Keith Chapman]

Check the valve clearances then get the throttle bodies balanced and the tick over correctly set.
then with your spare change spend £12 and subscribe to the forum

 

[ianran]

Sounds lioke throttle thingys out of wotsits, 10 mins for a decent BMW dealer to sort, if you bought it from em a gooden will do it for nowt.

Remember this, look at the size of the lumps sticking out either side of your bike, inside there is lumps only a little bit smaller than them moving left to right at a rate of knots. This is not a recipe for absolute smooth running!

 

[Deleted account 210609001]

Definitely a fault rather than a trait. Could be lots of things - coils, failed spark plug (which wouldn't necessarily show up by colour) fuelling fault, knackered lambda sensor, or just throttle bodies unbalanced.

Take it back to the dealer and ask them to sort it.

 

[drsylvester]

OK guys - thanks very much for your input. I'll email Balderstons today and see what they have to say and update this thread further when I know more.

Again, thanks to those who replied.
Derek.

 

[rdover]

Silly question ....... is the oil level OK, mine gets noticably lumpier as the level drops. Keep it about 2/3 full on the glass .

 

[drsylvester]

Here you go - here is the response I got from Balderstons:

"Hi Derek,
There is no problem checking anything out with us that's what we are here for.

What it sounds like is the bike settling down, I`m assuming that the injector bodies & valve clearances need adjusting which is done at the 6000 mile service, these can go out in time and will cause the running problems you describe. We can do this before if you are worried about it or can leave it until the service,let me know what you would like, I am booking from next week now."

Looks like you were spot on Keith...

Thanks again.
Derek.

 

[NeilG]

Had a coil fail on my old GS which created similar symptoms. This was missed by one dealer when it went in for a 12k service, but sorted by another a couple of weeks later.