back firing

Does your Spree/Elite already run great, and you're trying to make it quicker/faster? Need a monster motor swap? Discuss your ideas here.

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808allday
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back firing

Post by 808allday »

When I hit around 50 - 60 MPH bike starts to back fire. Could that be my main jet?
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808allday
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Re: back firing

Post by 808allday »

When my bike hit 50-60mph it back fires

Could it be my main jet or could it be my float in my carb.

What causes backfire anyway
Meloshameless
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Re: back firing

Post by Meloshameless »

I had popping sounds when my reeds were goin out, but google search carb tuning, i wanna say backfire falls under rich condition but cant remember.
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Re: back firing

Post by MrJumps »

The after fire, popping can be a LEAN condition or if it is truly backfiring through the carb it is RICH.
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808allday
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Re: back firing

Post by 808allday »

Its backfiring from the exhaust
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Wheelman-111
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Re: back firing

Post by Wheelman-111 »

Greetings:

This was explained to me by grizzled Sportster Cognscenti years ago. Under compression, the inhaled mixture is non-combustibly LEAN for several piston strokes. The fuel and air is wasted out the pipe until enough gathers in a of the header segment. After a certain number of cycles, the mass ignites at once producing the BANG!!
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