Spark plug gap?
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From: Lafayette, Louisiana
Not quite the whole story. It depends on how the engine is set up as well as load and environmental factors.
For example in cooler weather you can run a slightly larger gap for bit more crisp response and a fraction more power. In the summer, you can't do that and your gap needs to be slightly narrower to combat detonation.
That is just one over simplified example. Things like compression, ignition timing, air fuel ratio, weight of the bike with the rider, barometric pressure, and other factors come into play that are beyond the scope of this thread.
The factory spec is the best and safest bet for most conditions. Some gains may be attainable with a larger or smaller gap, but only when you are building bleeding edge performance and account for risk / longevity.
Long ago I was into all that stuff. Needless to say my Sportster I had at the time was a fairly brisk riding little bike.
For example in cooler weather you can run a slightly larger gap for bit more crisp response and a fraction more power. In the summer, you can't do that and your gap needs to be slightly narrower to combat detonation.
That is just one over simplified example. Things like compression, ignition timing, air fuel ratio, weight of the bike with the rider, barometric pressure, and other factors come into play that are beyond the scope of this thread.
The factory spec is the best and safest bet for most conditions. Some gains may be attainable with a larger or smaller gap, but only when you are building bleeding edge performance and account for risk / longevity.
Long ago I was into all that stuff. Needless to say my Sportster I had at the time was a fairly brisk riding little bike.
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