M8 on 2 plugs?

[Xyzzy]

If I pull the left plug boots off of my bike while it is running, the engine doesn't run very smooth. I kinda expected it to run normal since there are 2 other spark plugs to do the job.

Is this what you'd expect, or is my bike not right?

FWIW, I just put new plugs and fat plug wires on. I didn't think to test the "2 plug theory" with the stock stuff before I put the new stuff on.

[1FSTRK]

Probably not a good idea with an ecm.

With one plug per coil on the after market dual plug systems when you pulled one wire off or fouled a plug you were running the timing retarded. A one plug per cylinder system has more spark advance timing.

[Hossamania]

Right. Don't do that.

[Moparnut72]

I had a BMW R90/6. I bought it used with dual plug heads, but the ignition system was never upgraded to use them. I eventually added Harley coils and ran both plugs. It was amazing how much of a difference they made. The idle alone was a couple of hundred rpm higher when I first started it. I agree don't run it without plug wires grounded in some way, very hard on coils. I collect and use old outboards with magnetos. Doing that will burn out a coil in no time in one of those and a lot of those are now unobtainium.
kk

[K4FXD]

The Ign timing is set for 2 sparks in the cylinder, so by removing one the engine is instantly out of tune.

[HV]

Even a loose plug Cap on a plug of an M8 will retard the timing and make the Engine run Rough

[Xyzzy]

Thanks for all of the replies, I learn something new every day!

[hd06myway]

xyzzy can we call you Dyzzy?

[Xyzzy]

You can call me anything you want as long as you don't call me late to supper!