Author Topic: Jetting ???  (Read 1300 times)

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Offline evo550

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Jetting ???
« on: August 20, 2009, 08:48:16 pm »
Am I right in assuming that a bike jetted perfect for 500m above sea level, would run lean at sea level ?

Offline oldyzman

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Re: Jetting ???
« Reply #1 on: August 20, 2009, 11:22:47 pm »
Gday evo,
You could asume that, please consider the other factors, I think it goes something like this. High humidity / High Ambient temp / High altitude all result in less oxygen therefore more fuel, therefore runs richer.
"Others" please correct me if i am wrong as i would not like to mislead on this potentially expensive topic
OLDYZMAN
I have a soft spot japanese mxers with aluminium tanks. Two stroke classic Dirt Track...

Ji Gantor

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Re: Jetting ???
« Reply #2 on: August 21, 2009, 08:28:58 am »
The higher you are the less oxygen in the air or as it is called "Thin Air"
Less oxygen does promote a richer mix.

Yes a bike tuned at 500m above sea level would run lean at sea level if all other wheather conditions were the same.

Ji
« Last Edit: August 21, 2009, 08:31:23 am by Ji Gantor »

Offline lukeb1961

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Re: Jetting ???
« Reply #3 on: August 21, 2009, 09:58:05 am »
http://www.iwt.com.au/mikunicarb.htm

or  think.. think...   reaches for ancient edition of University Physics - ah yes, the Ideal Gas Law.  Recalculate from first principles.  25 marks  :P

Offline micks

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Re: Jetting ???
« Reply #4 on: August 21, 2009, 11:11:09 am »
rad