2005 crf 250 jetting - 6500 ft

trying to help my friend dial in his bike. Everythings stock except it has a slip on exhaust, running at 6500 ft elevation.

2005 crf 250

what should the jets be?



is the stock needle ok?

what position should the clip be in?



You need to first confirm existing jetting. Stock only means you have not checked.

Next clearly identify any problem. Exact actual throttle position. Bike temp, load, no load.

hu, well shouldnt there be a rule of thumb of what jets should be in there at this altitude? Why would it matter whats in there now to figure that part out? It runs fine, just trying to clean it up.. I can get all those specs, its just not in my garage to have a peek atm... Thanks for your help though

temp is between 65-85 degrees, and I dont know what you mean by load/no load

FCR-Tuning Guide

Basic Carb Theory

Jetting for Altitude and Weather

How can you adjust when you do not know what you have? How do expect us to know what needs fixing if you do not tell us? If the bike runs good, there is nothing to do.

Load/no load means when riding at a steady speed on the flat ground (no load) or at a steady speed up a hill (load).

thanks for those links, I will look at whats in there this weekend and come back.

so how does the load / no load work into the equation, I have never heard that before.

A bike that runs great under no load, and poorly under load is lean. A bike that runs great under load and poorly under no load is rich. A bike that runs fine under load or no load is probably jetted right or close to right. To get more accurate, a timed ctest is needed or special tools like a A/F meter and a dyno.

that makes sense great explanation...

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