We have developed a list of jetting specifications that we believe will help your bike run its very best. Please remember that sometimes the stock OEM jetting will work just fine, other times you may have to make an adjustment, so use our suggestions below as a guide to help with your jetting problem.

For two-stroke bikes, our jetting specs are for VP Racing C12 Racing Fuel at 0-1500 ft altitude, 70-85°F temperature, 32:1 pre-mix oil ratio. We recommend Maxima Castor 927 High Performance 2-Cycle Oil.

For four-stroke bikes, our jetting specs are for premium pump gas at 0-1500 ft altitude at 70-85°F temperature.

Please Note: The stock OEM jetting for your specific model is listed first, followed by our recommended jetting underneath that model.

2007

ModelMainPilotNeedlePosScrewPowerSlideNozzleLeakOther
Honda

CR85R14245NFSF31.5









Pro Circuit14242NFSF4











CRF150R13540NHNT32

1.5

60

Pro Circuit14042NHNR32

1.5

50Needle #16201-KSE-672
CR125R43055

32









Pro Circuit41050STK21.5









CR250R420406DGY26-6532

4.0S-7



Pro Circuit41037.56DGY26-6521.5

4.0S-7



CRF250R17542NKBT32.25





70

Pro Circuit17045NKBT31.5





45

CRF250X13040NCYU22





65

 



















CRF450R17842NJYR31.75





50

Pro Circuit17842NJYR31.75





50

Mammoth17542NJYR2







50

CRF450X14545NCVU22.5





70

Pro Circuit15545NCYS32.25





70Needle #16204-MEN-671
Yamaha

YZ8513845NBKF22.375









Pro Circuit13542NBKF22









YZ125410406CHY5-8042.25

4.0





Pro Circuit410356CHY5-8031.75

4.0





YZ25017850N3EW21507.0





Pro Circuit17548N3EW21507.0





YZ250F17842OBELQS







80

Pro Circuit18042OBELQ32





60

YZ450F16045NFLR41.25





55

Pro Circuit16542NFLR52





50

WR250F



















Pro Circuit



















WR450F16045NFNTfix1.5





60

Pro Circuit



















Suzuki

RM8512550NAAH22









Pro Circuit12548NAAH22









RM12537042.56CHY17-632









Pro Circuit370406CHY17-621.75









RM25016848NECJ31457.0





Pro Circuit16848NECJ31.5487.0





RM-Z25016245NLCT32.25

1.5

40

Pro Circuit16245NLCT42.25





40

RM-Z45017042NCYR32





35

Pro Circuit17042NCYR32





35

Kawasaki

KX65190255GSP6831.5

1.5O-0



Pro Circuit20027.55GSP6821.5

1.5O-0



KX8514045NAPE31.375

3.5





Pro Circuit13842NAPE21.375

3.5





KX10013845NAPF41.375

3.5





Pro Circuit13842NAPF21.375

3.5





KX25016250NFTG31.75508.0





Pro Circuit16248NFTG41.550







KX250F18240NHJT41.75





55

Pro Circuit17042NCYS32.5





50

KX450F17542NCVR41.75





70

Pro Circuit17542NCVR42





55

Mammoth17242NCVR31.5





55

KTM

KTM 65 SX20025

41.5









Pro Circuit22032.5

41.5









KTM 250 SX-F17540OBETP51.25

1.5

No Leak

Pro Circuit17840OBETP42

1.5

No LeakWire Accel. Pump
KTM 450 XC17842











No Leak

Pro Circuit



















2006

ModelMainPilotNeedlePosScrewPowerSlideNozzleLeakOther
Honda

CR85R14245NFSF31.5









Pro Circuit14242NFSF4











CR125R43055

32









Pro Circuit41050STK21.5









CR250R420406DGY26-6532

4.0S-7



Pro Circuit41037.56DGY26-6521.5

4.0S-7



CRF250R17240NHFS31.75





70Raise Float 2mm
Pro Circuit17042NHFT32





45Remove Float Bowl Baffle
CRF250X13040NCYU22





65

Pro Circuit15842NCYS42.25





55Needle #16204-MEN-671
CRF450R16842NCYQ41.875





55

Pro Circuit16842NCYQ42.25





55

CRF450X14545NCVU22.5





70

Pro Circuit15545NCYS32.25





70Needle #16204-MEN-671
Yamaha

YZ8513845NBKF22.375









Pro Circuit13542NBKF22









YZ125410406CHY5-8042.25

4.0





Pro Circuit410356CHY5-8031.75

4.0





YZ25017850N3EJ21507.0





Pro Circuit17548N3EJ21507.0





YZ250F17842OBELQ3







80

Pro Circuit18042OBELQ32





60

YZ450F16542NFPR42





55

Pro Circuit17050NFPR52.5





50

WR250F



















Pro Circuit



















WR450F



















Pro Circuit



















Suzuki

RM8512550NAAH22









Pro Circuit12548NAAH22









RM12537042.56CHY17-632









Pro Circuit370406CHY17-621.75









RM25016848NECJ31457.0





Pro Circuit16848NECJ31.5487.0





RM-Z25017840OBEKS4







60

Pro Circuit16542OBEKR42





60Needle # K1618-70069
RM-Z45017042NCYR32





35

Pro Circuit16845NCVR32





65

Kawasaki

KX65190255GSP6831.5

1.5O-0



Pro Circuit20027.55GSP6821.5

1.5O-0



KX8514045NAPE31.375

3.5





Pro Circuit13842NAPE21.375

3.5





KX10013845NAPF41.375

3.5





Pro Circuit13842NAPF21.375

3.5





KX25016250NFTG31.75508.0





Pro Circuit16248NFTG41.550







KX250F18040NCYU31.75





60

Pro Circuit17042NCYS33





50

KX450F17542NCVR31.75





70

Pro Circuit17542NCVR32





55

2005

ModelMainPilotNeedlePosScrewPowerSlideNozzleLeakOther
Honda

CR85R14245NFSF31.5









Pro Circuit14242NFSF4











CR125R43055

32









Pro Circuit41050STK21.5









CR250R420406DGY26-6532

4.0S-7



Pro Circuit41037.56DGY26-6521.5

4.0S-7



CRF250R17042NCYQ31.75





70

Pro Circuit17042NCYQ31.5





70

CRF250X





4











Pro Circuit15842NCYS42.25





55Needle #16204-MEN-671
CRF450R16842NGGQ41.875









Pro Circuit16842NGGQ42.25









CRF450X14545NCVU22.5





70

Pro Circuit15545NCYS32.25





70Needle #16204-MEN-671
Yamaha

YZ8513845NBKF22.375









Pro Circuit13542NBKF22









YZ125410406CHY5-8042.25

4.0





Pro Circuit410356CHY5-8031.75

4.0





YZ25017850N3EJ21507.0





Pro Circuit17548N3EJ21507.0





YZ250F18242OBELR41.875





90

Pro Circuit18045OBELR41.875





90

YZ450F16545NFLR4







72

Pro Circuit16545NFLR41.5





72

WR250F16840OBERP4







95

Pro Circuit18042OBELR41.25





95

WR450F16545NFNT4







50

Pro Circuit16540NCVQ31.75





50

Suzuki

RM8512550NAAH22









Pro Circuit12248NAAH22









RM12537042.56CHY17-632









Pro Circuit370406CHY17-621.75









RM25016848NECJ31457.0





Pro Circuit16848NECJ31.5487.0





RM-Z25017840OBEKS4







60

Pro Circuit16542OBEKR42





60Needle # K1618-70069
RM-Z45016542NCYR41.25





35

Pro Circuit



















Kawasaki

KX/RM65190255GSP6831.5

1.5O-0



Pro Circuit20027.55GSP6821.5

1.5O-0



KX8514045NAPE31.375

3.5





Pro Circuit13842NAPE21.375

3.5





KX/RM10013845NAPF41.375

3.5





Pro Circuit13842NAPF21.375

3.5





KX125420406CHJ10-8232.5

5.75





Pro Circuit400356CHJ10-8221.5









KX25016250NFTG31.75508.0





Pro Circuit16248NFTG41.550







KX250F17840OBEKS4







60

Pro Circuit16542OBEKR42





60Needle #16187-0069