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FCR39 Rebuild Cheking My Math

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I am in the processing of pulling my FCR39 and giving it a full clean after sitting all winter.

Can you please validate my jetting is correct.

Minnesota 700 above sea level.

2013 DRZ 400SM 3X3, MRD full system, K&N filter.

160 main jet
200 main air jet
EMN needle
clip 3
45 pilot jet
Stock FCR pilot air jet
R&D Racing Flex Jet Fuel Mixture Screw 2 1/2 turns from closed
o-ring mod

Thanks for the help.

 

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Looks right, but each carb and bike varies.  Tweaking on the fuel screw may be needed, and verify your AP is working correctly.

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How does it run through the range ? 

You could go slightly leaner on the main , i got better throttle response with a slightly leaner needle ( the next needle down from EMN )  .

i am talking only slightly 

I bought a used air box cover and added some small vents too , again .. crispy throttle response 

my elevation is around the same as yours , but variable due the the hills .. Here ( Down Under ) 

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Thanks guys.

The bike is strong through the rev range but not very steady at idle.

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try screw at 0.5 from closed.  better or worse?

fcr-mx with 100 pilot air jet usually needs a needle with leaner root diameter or at least a smaller pilot jet. emN needle was perfect for fcr slant body, not for fcr-mx

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On 3/29/2017 at 8:48 AM, rraiderr said:

Thanks guys.

The bike is strong through the rev range but not very steady at idle.

 Fine tuning your fuel screw should sort out the idle

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why is the stock 80 air jet not used , i see 100-200 air jets are very popular !
im interested in this !

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33 minutes ago, F.R.E.D said:

why is the stock 80 air jet not used , i see 100-200 air jets are very popular !
im interested in this !

Stock is 100 pilot air jet and 200 main air jet

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1 hour ago, Craigo said:

 Fine tuning your fuel screw should sort out the idle

Great to hear from you Craigo, hope everything on you end is awesome.

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8 hours ago, 30x26 said:

try screw at 0.5 from closed.  better or worse?

fcr-mx with 100 pilot air jet usually needs a needle with leaner root diameter or at least a smaller pilot jet. emN needle was perfect for fcr slant body, not for fcr-mx

I may the other needle.

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My fcr slant came off of a stock E Drz and has a 80 air jet , I guess I should put a 100 in its place ? Why would someone Change it ? I'm Curious
Thanks for the reply craigo

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4 minutes ago, F.R.E.D said:

My fcr slant came off of a stock E Drz and has a 80 air jet , I guess I should put a 100 in its place ? Why would someone Change it ? I'm Curious
Thanks for the reply craigo

US specs maybe a little different to the rest of the word...What pilot jet has it got ?...I am guessing a 42 if it runs a 80 paj as stock

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Yes I believe it has a 42 pilot
I have a 45 sitting here
California 0-4000 ft elevation

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Jd jet told me to leave the 80 air in it and follow there directions in the kit ,
I see everyone has emn needle 160 main 45 pilot 100 air
With great results

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