tomtietjen
slowrider
The last couple tanks of gas on my 04 1150 GS have only yielded 35 mpg ( I usually get 45 ) so I pulled my plugs to see how they looked today. Plugs looked OK with the right secondary a little black, but when I tried running the bike on the primary plugs it would run on one cylinder only. Disconnecting each primary plug did not have the same effect, bike started and ran ok. I used a dummy plug each time I pulled a Plug wire and the primary coils seem to be working ( getting spark ) Is it possible for the primary coils to be bad but still sparking since the bike will not run on the primary plugs alone but will run on the secondary plugs alone ?
