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Replacing the Jets

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Replacing the Jets

By Jim Sloot and forum posts by Bikenut

This procedure requires removal of the carburetor assembly from the motorcycle and partial disassembly of the carburetors. Do not attempt this procedure unless you are confident you can complete it successfully. Carburetors have delicate adjustments and are easily damaged. A step by step procedure is not described here as it is assumed you already know how to remove the carbs and replace the jets. This section is mainly to show the jet sizes required for doing the modification.

Rejetting is sometimes required if you have installed aftermarket exhaust or modified the air intake system. The following table shows the stock main jets as well as the required jets for increasing them by one size and by two sizes. These are designated as MOD+1 and MOD+2, respectively.

Carb Stock MOD+1 MOD+2

1 122.5 125 127.5

2 122.5 125 127.5

3 117.5 120 122.5

4 120 122.5 125

To rejet up one size, some rearranging of jets is required.
Move jet from carb 1 to carb 4.
Move jet from carb 4 to carb 3.
Replace jets from carbs 1 and 2 with the 125 size - 2 required.
To rejet up two sizes, you will need to purchase 2 of 127.5 and 1 of 125. Good luck.

Last update: 04:54 PM Sunday, September 26, 2004

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