There seems to be no noticeable changes whatsoever.
That seems to be true with my two interstates; one OE and one 4* Air Lake. (except the 4* bike required high octane to avoid knocking for a long time)
When I first installed the 6° trigger wheel I noticed I did get a little bit better gas mileage. Now, that doesn't matter much anymore, and running regular grade gasoline was the incentive. I never experienced any knocking whatsoever, even though it was the 6° wheel.
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