Poorly twin spark 1150 Rockster

[(RIP) trickytree]

Been away for the weekend and on the way home noticed the bike wasn't running quite right. Quite bad surging through town, much worse than normal. Tick over slightly lumpy and engine not as crisp as normal, most noticeable when blipping the throttle on down changes.
Power seems ok further up the rev range but there's a bit more vibration than normal.
I'm just waiting for the bike to cool down so as I can wash it before I start investigations, wondering if these symptoms are familiar to anyone?

 

[Steptoe]

Could be one or both of the main coil caps are failing - very simple to test. Pull off both lower secondary spark plug caps and try starting and running engine on just the main spark plugs. If one or both have failed or are failing your bike won't start or will run very rough or run on one cylinder.

 

[Roger 04 RT]

Does the secondary coil get damaged by running with both plug wires pulled? Some say so but I've wondered.

 

[Steptoe]

Does the secondary coil get damaged by running with both plug wires pulled? Some say so but I've wondered.

I very much doubt it despite what you may read.

I've never had any problems since the twin spark engine first appeared 13 years ago.

If you set off to ride around the world with the plug leads pulled you may get trouble, but for doing a simple quick test no problem.

 

[Kenny]

Symptoms you describe just happened to me on my Rockster...new stick coils just inserted.

 

[(RIP) trickytree]

Thanks very much peeps, just got in from the garage and guess what? ....... Stick coils!

Motobins open day this Saturday with 20% off so that's handy.

 

[(RIP) trickytree]

Went to the Motobins open day this morning and got a couple of stickies......picture on the website clearly shows the aftermarket Beru items but when I got home and opened the packaging I was pleasantly surprised to find genuine BMW parts....all for 70 quid a pop with the 20% discount.
Bike back to running like a champ again