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Are the two spark plugs per cylinder a redundant spark or does it serve another purpose. I was holding my finger over the spark plug hole which should suck my finger in but it kept blowing it off with force. It almost felt if it was the exhaust stroke that was blowing my finger.

Help me understand please?

Grace!
Richard
 

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The extra plugs are for the extra spark required to run the OHV configuration....in theory, with one good plug in each, you could run the bike with one connected to each (both holes filled)...if needed...yet another crappy kawi design to compensate for other engineering flaws...they could have done it like on the 800 Kawi, single plug in the center, and a manifold that sucks off of one carb.....they were in a hurry to put Harley outta biz I think....very poorly thought out....and we gotta deal with it...
 

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It was the compression stroke that blew your finger off the hole, it should do that. You won't feel the exhaust stroke because the exhaust valve should be open and the air going out the pipe.

I disagree that it's a crappy and poorly thought out design. I think it's a good design. For a long time, multi-valve head designs have made induction better. What we have are two intake and two exhaust valves per cylinder, with a spark plug between each set. It's much better for delivery to have the intake charge divided and each coming to it's own local spark, It's getting more air into a smaller space in the amount of time given (intake stroke). With two charges and two sparks, the flame front is going to start simultaneously on each side and meet in the center of the chamber.

It's got two sets of induction and spark in each cylinder. It's almost a hemi-head, but possibly a poly-head.

This engine may be screaming for a blower, but a couple more wheels might be useful.
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It's almost a hemi-head, but possibly a poly-head.
Ever see a Dodge with 16 spark plugs ?....all Im sayin...the dome design was poor, IMO...would have been just as effectice with a single spark between the 2 domes had they been shaped differently...

BTW...I hate camchains too...gimme pushrods, rockers and lifters...less to go bad, and easier to work on...the most reliable OHC setup on a bike, IMO was on the older Hondas....it was when they started goin from SOHC to DOHC is when the sheit went downhill....not performance wise, but reliability...
 
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