Genuine Keihin jets provide the best replacement or calibration solution for your Keihin carburetors.  Do not use an imitation, nothing substitutes for OEM quality and Keihin jetting is guaranteed to be the exact size indicated because of high manufacturing tolerances.  The FCR and FCR-MX slow air jet conversion kits fit all Keihin FCR and FCR-MX aftermarket carburetors.  They replace the 99101-ZF5 (old 99101-124) slow air jet and allow you to fine tune to an infinite numbers of positions without replacing any jets!  Just follow the chart in the details page and you can tune it to any jet size you wish. 


The kit contains a screw and a spring, the jets have a 7mm thread diameter.  You remove your fixed size ZF5 slow air jet and install the screw with the spring installed over the end.  See the chart below for the jet size to adjustment correlations.

Please Note:  These adjustable air jets do NOT fit all OEM Keihin FCR carburetors, exceptions are listed below.  Please verify fitment before purchasing.  We have not tested all OEM models, however some OEM applications include but are not limited to:

• Keihin FCR horizontal draft carburetors
• Keihin FCR down draft carburetors
• Keihin FCR-MX carburetors
• Kawasaki KLX400R (03)
• Kawasaki ZX750 with Keihin FVKD (96-97)
• Kawasaki ZX-7RR with Keihin FVKD (96-97)
• Suzuki DR-Z400E with Keihin FCR carburetors
• Yamaha WR400 with Keihin FCR carburetors
• Yamaha YZ400 with Keihin FCR carburetors
  
• Yamaha YZ426 with Keihin FCR carburetors