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We've tried them on my brother's '04 CBR1k once......they won't work for everyday commuter bike cause they need to keep your rpms above middle range but the most important is that they don't work sufficiently with less than 110 RON fuel.
 

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Discussion Starter #3
I understand that they are not for commuting, luckily neither is the sp1 ;-)

why do you think it needed 110 fuel?
 

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My old '72 Kawasaki F9 Bighorn dirt bike used surface gap plugs.
It also had a CDI ignition system that put out 50KV as well.
Typical 18KV ignition system just isn't hot enough to keep the plugs from fouling.
A surface gap plug is about the coldest plug you can get.

The CDI system on my F9 put out such a hot spark that I never fouled a plug, even when the nut on my primary gear backed out and milled a hole in the case, allowing gear oil to get sucked into the carb (2-stroke, rotary valve engine).
It would just wear out the plugs internally over time.

When checking the ignition system, it was never a problem viewing the spark.
On an 18KV system, you had to block sunlight to see the spark.
On that 50KV system, it was like looking at a welding arc. It snapped and crackled it was so hot. And if you got your hand too close, it would bite big time and hurt like a bitch.
 

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Discussion Starter #5
A two stroke with an oily mixture and high compression can pretty much blow out a spark its true

surface discharge plugs are available in the correct heat range, lots of ducatis run surface discharge plugs as original equipment
 
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