I'm just trying to figure out exactly how this engine works. I'm familiar with Internal Combustion engines, but not motors with 2 spark plugs per cylinder. I would think that the second plug is just an extra spark to make sure the fuel vapor is all burned up but, it doesn't seem like that's the case. If the 2nd plug is bad or not firing you can definitely feel it. Why is that? What is the "job" of the secondary plug, does it fire during a different part of the stroke or something? I just can't figure out why that second plug not firing would make such a difference??
(2000 RSV Mille)