Kdx 1997 200 Fmf Fatty Jetting pls help

[treborlennon]

Trying to get jetting and gearing right for Cross Country in Northern Ireland. We just added fmf fatty and went up to a 180 main jet. The bike seems still to have a flat spot down low but has good top end when she gets going. I am used to riding a wr450 which just pulls pulls pulls but kdx doesnt seem just right. The grearing on kdx is 13/49. I am wanting to use kdx for Cross country events which are over unsed farmland hillside, covered in heather and bog . I am finding the WR to heavy and big for this sort of going as ther is no speed involved.Its all climbing and desending and navagiting bogland kdx is ideal size just need to get it running right down low.

 

[duzmor]

Hi did you read this

http://justkdx.dirtrider.net/ Tech Tips

Or go to FMF Tech support they will tell you the jets to run

http://www.fmfracing.com/home.asp

Duz :) :)

 

[Rhodester]

Instead of going up to a 180 (160 is stock in the states) I'd go to a 155. You should see a noticeable power increase with that main jet. Your flat spot is probably due to a needle issue. I'd go to a 45 pilot (or even a 42), set your air screw at 1 1/2 out for starters, put in a CEM needle (if using the stock slide) in the #3 clip position, and start my testing to fine tune from there. You'll immediately like the difference. Also, keep the air box lid on...just remove the snorkel (...another flat spot issue).

 

[Rhodester]

Oops, I meant to say a DEM needle, however, some like that CEM a bunch too. The stock slide (throttle valve) is a #5. Use a DEL with the #6 slide, or a DEK with the #7 slide (my preference).

BTW, what reeds are you running??