popping and no longer smooth

[dpft]

My R1200GS is a 2005 bike with 58,000 miles on the clock. Up until a short while ago it was running really well but of late on the overrun it is popping and banging and at low revs it is rough to ride. It has jut had new plugs and filters and a good service but there is no difference. Any suggestions please. I have been given the following suggestions: Weak mixture. Valves pitted. Air on the exhaust side. (I was told it is airtight on the inlet side.

 

[comberjohn]

From what I've read on the forum, I'm guessing it might be your coils. I believe the earlier models have coils that eventually overheat and fail.
Have a seat and someone who's been there will be along soon.

 

[AlexG]

This post in a earlier thread describes checking the coils: clicky link.

 

[NZRalphy]

Air leak at the throttle body

 

[fatbaldbob]

I had a similar problem and it turned out to be the lambda sensor.

 

[harry the cat]

No longer smooth?

Sad to say the 1200GS ceased to be smooth some years ago. What you need is a Ducati Scrambler, an open face helmet, and a full beard

 

[Steptoe]

Before stabbing away in the dark and guessing get someone to plug in a GS911 and see if any faults show up.

 

[tuftywhite]

I had a similar problem. Rough at low revs, didn't pick up nicely from tickover.

Replaced the secondary coils (the ones underneath) with the aid of Eddy (I think) now it's smoother than a smooth thing.

 

[solidstate100]

Before stabbing away in the dark and guessing get someone to plug in a GS911 and see if any faults show up.

Start here ^ instead of guessing and/or taking (well meant) advice that may or may not have anyting to do with it.............

 

[tuftywhite]

I may be wrong but I didn't think failing coils showed up on the GS911.

I'm happy to be corrected.

 

[Bendy toy]

Dead coils show a low power signal to the failed coil. Intermittent failing coils probably won't show up directly so are diagnosed by the symptoms they generate.

If you don't have a 911 - the simple test is unplug each coil and see if the engine behaviour gets worse (coil working) or stays the same (coil not working). My 2008 had the old black painted coils. The primaries smelled burnt though were still working ok when not fully up to running temperature. The clue was excessive fuel consumption and sooted up lambda sensors. Intermittent sparks cause the engine to run rich. Both of my primaries were on the way out so testing without the 911 was hit and miss.

When my coils eventually failed completely the cause was obvious but a 911 might have helped when they were misfiring.

The popping could be a coincidental air leak. Mine pops like a goodun with the baffles out but recently began to tick from on exhaust port (exhaust pipe to head gasket leak). The popping has got worse.