Jetting

[rames90]

I know this has probably been asked a thousand times, but I get more confused with each differing source of information I find. The FMF Website suggests a 50/48 pilot, 155 main and 2nd clip position setting for a 2000 KDX 220 bike with an FMF pipe, this is very different from the 42 pilot, 145/148 main, 2nd clip position suggested on just KDX (at least I think it is, I'm new to this). As I understand it the higher the numbers the richer the mixture.

The only engine related mods I have to my bike are the air box lid modified and a KG-35 FMF pipe. What are the stock 2000 KDX 220 jetting settings anyway? The owners' manual is not helpful. My concern is the stock jetting being too gasoline rich for my bike with these mods. Is it necessary for me to adjust the jetting?

Thanks in advance for any advice. :(

 

[cycleboy]

You can get the jetting specs for your 220 in the owners manual. On page 74 it lists optional parts. Under carburetor Jetting Parts it shows all the optional stock parts. Note which ones are missing for the 220. These are the stock jets and needle. For the 220 it came stock with a 145 main, 42 pilot, R1173L needle. Same goes for the rest of the specs. on this page. Hope this helps.

 

[Canadian Dave]

If that's the jetting recommendations FMF offers for the 220 then they are mistaken. I don't expect your 220 would run for more than a couple seconds with a 155 main and 48/50 pilot jet before it fouled the plug.

Your stock jetting should be really close given the altitude and average temps in the Calgary area. Move your jet needles clip to the second from the tops position, do a plug reading at WOTand fine tune your main jet based on the results.

David