Ktm 250sxf Jetting From 2005 To 2009

Nothing required short of some fiddling

Sx250f 2008

Most of the MXA wrecking crew's jetting experience on the KTM 250SXF has involved making small fine-tun-ing adjustments. To make the most of the KTM 250SXF, you have to learn to feel where the problem is before you can iron it out. We have fiddled with the fuel screw, adjusted the accelerator pump (both the rod length and the cam setting) and added after-market float bowls with leak jets. As far as the actual hard parts in the carb go, we have rarely had to make a lot of changes to the main, pilot or needle. Although occasionally, we have gone one size richer on the main or pilot, but we have never changed a needle or a leak jet (largely because it wasn't until 2009 that the 250SXF's Keihin carb got a leak jet).

As a rule of thumb, if the engine sounds raspy, we look to external adjustments as opposed to brass.

As with every jetting guide, there are caveats about temperature, altitude, riding style, hop-ups and personal taste. Our numbers are suggested starting points for motocross racers (the stock jetting, when changed, is included in parentheses). The fine tuning is still up to you.

2009 KTM 250SXF JETTING Main: 175 Pilot: 40 Needle: OBEKP Leak jet: 50

Clip position: 5th from top Fuel screw: 1-1/4 turns out (1 stock)

Notes: KTM switched from an OBETP needle in 2008 to a richer OBEKP for this year and added a leak jet. Initially, there was a hesitation off the bottom, most noticeably after the engine warmed up. On the accelerator pump, we turned the screw in until it made contact with the pump and then backed it out 1/4 of a turn. In our experience, fiddling with the adjustment screw pays big dividends on the KTM carb. From the contact point, back the adjustment screw out (counting turns as you go). This is a must-do adjustment.

2008 KTM 250SXF JETTING Main: 172 (175 stock) Pilot: 42 (40 stock) Needle: OBETP Leak jet: No leak jet Clip position: 4th from top (5th stock)

Fuel screw: 1-1/2 turns out (1 stock)

Notes: We went leaner on the main and richer on the pilot. Adjust the accelerator pump arm, located inside the diaphragm housing, so that it is 1mm away from base. The 2008 KTMs do not have leak jets. You can add a leak jet with a Boyesen or R&D float bowl.

2007 KTM 250SXF JETTING Main: 172 Pilot: 42 (40 stock) Needle: OBETP Leak jet: No leak jet

Clip position: 5th from top

Notes: Across the board, the 250SXF's 39mm Keihin FCR is decent for most hot-weather riding. Cooler temps will require a richer pilot and a couple of clips on the needle. 2007 KTMs did not have leak jets. You can add a leak jet with a Boyesen or R&D float bowl.

2006 KTM 250SXF JETTING Main: 168 Pilot: 40 Needle: OBETP Leak jet: No leak jet Clip position: 5th from top Fuel screw: 1-1/4 turns out Notes: 2006 KTMs did not have leak jets. You can add a leak jet with a Boyesen or R&D float bowl.

2005 KTM 250SXF JETTING Main: 168 Pilot: 40 Needle: OBETP Leak jet: No leak jet Clip position: 5th from top Fuel screw: 1-1/4 turns out Notes: 2005 KTMs did not have leak jets. You can add a leak jet with a Boyesen or R&D float bowl. □

Kx450f Pilot Jet2005 250sxf

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Responses

  • asmara
    What is the best jetting for ktm 250f 07?
    8 years ago
  • zahra
    What size pilot jet ktm 250sxf?
    8 years ago
  • taneli
    How to jet a carb ktm 250 sxf?
    8 years ago
  • amanda
    What is stock jetting for 08 ktm 250sxf?
    7 years ago
  • karita
    Where are the carb adjusting screws on 250sxf ktm?
    6 years ago
  • osman
    How to adjust the accelerator pump ktn 250?
    6 years ago
  • ute
    How to adjust float on 2007 ktm 250 f?
    6 years ago
  • andwise
    How to take off 06 ktm 250 sxf carburetor?
    6 years ago
  • KAIJA
    How to adjust 2008 ktm sx250f carb?
    6 years ago
  • craig
    ktm 400 2001 carp leaking fuel from the rod accelerator pump some say give the carb a tap and some say it could be the diaphragm needs replacing ?
    6 years ago
  • Pansy
    How to adjust ktm 250 carburator?
    6 years ago
  • FARRAH
    What fuel for ktm 250 sxf 2007?
    6 years ago
  • michael
    What kind of carb comes on 07 ktm 250sxf?
    6 years ago
  • aaran gibson
    Which cam is which 08 sxf250?
    6 years ago
  • REETA
    What size jets come in a ktm 250?
    6 years ago
  • Askalu
    What is the stock main jet in a ktm sxf 250?
    6 years ago
  • nelma
    How to adjust a leak jet on a 06 ktm 250 sxf?
    6 years ago
  • josefiina
    How to adjust fuel on 2007 ktm sxf 250?
    6 years ago
  • Fiorenzo
    How to set a 2006 ktm 250sxf carburetor?
    4 years ago
  • jamila
    How to install carb on ktm 250 sxf?
    4 years ago
  • tito
    How to adjust randd powerbowl ktm sxf?
    4 years ago
  • eveliina
    How to adjust 08 250sxf accelerator pump?
    4 years ago
  • annett
    How does accelerator pumpwork onktm 250 xcf?
    10 months ago
  • Leslie
    What size stock needle 2007 ktm 250 sxf?
    7 months ago
  • Heikki
    What does a split stream carb insert do on a ktm sxf?
    5 months ago

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