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FCR39MX jetting 7000FT

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I will try to keep this clear because there are a million jetting threads already. Have a FCR39mx in the mail heading my way. Bike is 400S, stock with 3x3, E header and fmf Q4 slip on. I am at 7000ft and mostly ride 5000-9000 feet. What would be a good starting jetting for me?

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1st thing is verify the float level is at 9 mm. Mine was less than 8. Don't know if it had a rough ride in the postal service or it was set at saki thirty at the factory. Float level influences all the jet circuits.
I would try the EMR 4 clip and a 155 main to start .
Hopefully you bought the R&D Flex jet as well? Start are 2 turns out and set from there.

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2 hours ago, ohiodrz400sm said:

1st thing is verify the float level is at 9 mm. Mine was less than 8. Don't know if it had a rough ride in the postal service or it was set at saki thirty at the factory. Float level influences all the jet circuits.
I would try the EMR 4 clip and a 155 main to start .
Hopefully you bought the R&D Flex jet as well? Start are 2 turns out and set from there.

That  is close to what I was thinking. Maybe I will get a 150 and a 155. 

Do you think the flex jet is better than extended fuel screw? I have read that some of the fuel screws meter a little differently and need different piolet jets. How does the flex jet do?

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FCR jetting database for reference;

https://docs.google.com/spreadsheets/d/1HNSB3DrqJqHTInjVDKKS4HNSHZPbdK0ElbfNI5HxuZg/edit#gid=570401124

I didn't like the feel of the flexjet extended screw as much as the James Dean extended fuel screw.Both work well though.It's a matter of personal preference.

The drz seems to prefer the R root diameter needles(emr,ncyr,jd red).The emn is too junky at small throttle openings and is overly rich even at sea level with the 45 pilot jet.I'd start with a 42 pilot jet and leave in the #100 pilot air jet.

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That  is close to what I was thinking. Maybe I will get a 150 and a 155. 
Do you think the flex jet is better than extended fuel screw? I have read that some of the fuel screws meter a little differently and need different piolet jets. How does the flex jet do?


Do I think it is better? Yes. You can literally reach down at a traffic light and adjusts it.

I have read the Kientech extended fuel screws for the stock carburetor don't work that well with JD Jetting's 25 pilot setting. I have not heard this reported with the R&D and it's not my experience with any bike I have used it on.

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