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03 yz125, rejet for big bore

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I have a Athena 144 kit for my 03 yz125 , does anyone know if I have to rejet or do anything to the bike so it will run properly with the big bore kit

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I know that some people have been told to keep the stock jets when they got their 300 kits for the yz250.

I think it all depends on your elevation and temperature, most bikes run rich so when you get a ported motor and bigger displacement, the stock jets tend to be best as they at that point lean it out a bit.

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When we went to 134cc we had to lean the main two steps and the pilot 1. It's better, but still kind of 'fat'.

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