What series pilot??

2 replies to this topic
  • Uponone420

Posted April 23, 2009 - 05:07 AM


Hey guys, I know when you start a new thread, you suppose to search first. I did this and I found my answer, unfortunately I forgot it and can't find it again. The question is what series pilot is in the FCR Keihin 39. I believe it is a 21 series. Also since I'm being lazy/efficient can anyone tell me the stock needle position. Just bought a 450 and who ever jetted it has it runnin 178 main at slightly above sea level! Therefore I have reason to believe the rest of the carb is screwy. Thanks for yalls time

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  • wondermuscle

Posted April 23, 2009 - 08:20 AM


What year is the bike?

Yes it is a series 21 pilot jet.

178 sounds a bit oversized.....

Check the Jetting Data base for some help with specific jets to use. There is tons of great info in the link below.


  • Uponone420

Posted April 24, 2009 - 05:56 AM


Its an 06. I agree it is really rich. I am going to go with a 48 pilot and 168 main. Dont know about needle clip yet. Picked the bike up bout a month ago.

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