Yes, people always forget how iffy the ignition coil sticks can be.
The stick is a 9cm-long black cigar which fits tightly in the tunnel in the cylinder-head that leads to the spark plug - the upper spark plug if your bike has 4 plugs. It suffers from metal corrosion due to condensation and also winding-breakdown due to heat.
Several experienced 1150cc boxer bike owners have abandoned the coil-in-tube design and changed to remotely-located Ford coils which are much, much cheaper. But that requires some electronics knowledge and the ability to fettle, which some owners aren't interested in - for obvious reasons.
However, the new generation of stick coils sleeved in stainless steel seem more resistant to corrosion and also maybe heat.
But it's easy to forget that many, many fuelling and bad-running problems in a 1150cc motor are simply due to coil sticks that are on their way out. IMHO, the first thing to check when there's trouble with the motor is the coil sticks. They're so easy to swap out if you have that little 3rd-party aluminium coffee-cup sized puller, instead of the brittle plastic version that's in the toolroll, and a pal with a similar bike, because the same stick fits most boxer engines that were OEM fitted with sticks.
Here's the
Motorworks modern replacement.
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For days i scratched my poor old bonce as to why the bike had suddenly started running like a bag of shite and even began cutting-out mid-ride. Forum members suggested many different possible causes, but the problems were instantly solved by my local bike serviceman finding that the stick in my left-hand cylinder-head had noticeable corrosion, and when he replaced it with one temporarily lifted from a nearby R1200 bike in his garage that was awaiting a general service, all my bad-running and cutting-out problems instantly vanished.
I've now bought two new ones and the 1200 owner is now oblivious to our borrowing, 'cos he's got his own stick back. My bike has only 25K miles on the clock.
