I'm sure my experience isn't endimic of ALL coil issues, but I think it was pretty standard. The bike would idle "fine" and would putt around at parking lot speeds without any negative indication. In fact, even two BMW mechanics rode the bike and found no problem. I guess they rode like Grandma because as soon as I got back on the bike it nearly threw me off with all the bucking. Another rider at that BMW shop, an amateur racer, took it out and immediately came back with "yeah, it's shit."
In other words, at least in my experience, I could take both primaries out and the bike would idle. I could take any 3 coils out and it would idle a little. I could ride around on any 2 coils. But under load, even up to all 4 coils, it would buck strongly, as if someone was hitting my kill switch over and over while I was accelerating.
A coil later (though I replaced basically all in my troubleshooting) and it was as good as new. (I guess I have plenty of spares, right)?
You are kind of going down the rabbit hold of "why coils suck" which happened a little in my thread too. Perhaps in your case, you should ride someone else's 1150 and see if it performs the same way?
BMW GS and Yamaha WR250X/R (split personality)
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