(snip) I know the system you speak of on the Cub. Cub's parent company, MTD, introduced it a few years ago. I can speak of bitter experience of the need to use resistor spark plugs in whatever engine is used on these units. They wont mow in reverse with non-resistor plugs, or at least they didn't when I worked for an entire week just to discover the fact. Got a nice, MTD jacket once I figured it out. Didn't help my ego much, though.
With the Cub, I engage the rio switch when I start mowing, and leave it on until I stop the PTO. What does resistor plugs have to do with it? (it's a twin) Is the rio switch operated by RF signal?
That's what Cub, and the engine manufacturer wanted to know. Both alternated between blaming each other, and claiming that what I was describing was impossible, and I must have overlooked something else. I finally pulled an identical tractor off the showroom, and fabricated a wire harness to allow me to operate the engine of one tractor with the electronics of the other's chassis. The problem followed the engine, so that narrowed it down.
Turns out the non suppression plugs interfered with the ecm that controlled the reverse switching. They asked me to call when I figured it out, and when I told the tech what it was, there was dead silence followed by him exclaiming that "this one's going up on the wall!"
A few weeks later MTD issued a service bulletin advising the need to use resistor spark plugs. The jacket was nice, but not worth an entire week's worth of head scratching.
"Forget pounds and ounces, I'm figuring displacement!"
If we accept that: MBG(+)FGSF(=)HBG(F1) And we surmise that: BG(>)HBG(F1) while GSF(<)HBG(F1) Would it hold true that: HBG(F1)(+)AM500(x)q.d.(=)1.5lbGRWT? PB answer: It depends.
