Fcr 39mm Jetting

Just picked up a FCR off thumpertalk, not exactly sure what to jet it to. Currently my bike has a Bigbore, E model cams, MRD ssw, 3x3, uni filter. Elevation is at 1,000 ft above sea level. temps from 45-100 degrees, some days high humidity. (Shit Wisconsin weather). I really appreciate any help.

 

Im running pretty close to you i got 160 main, 42 pilot(used to have 45) and emr needle 3rd clip...

Just picked up a FCR off thumpertalk, not exactly sure what to jet it to. Currently my bike has a Bigbore, E model cams, MRD ssw, 3x3, uni filter. Elevation is at 1,000 ft above sea level. temps from 45-100 degrees, some days high humidity. (Shit Wisconsin weather). I really appreciate any help.

 

open or corked pipe.?

Fully open.

Consider a 155 main jet

I got a buddy that has pretty much same exact setup except for bb. He runs a 158 main 3rd clip down. I was going to start off with the 155 main 3rd clip down.

Use a 155 main jet,

EMN needle clip 3 

45 pilot jet

2 turns fuel screw

Remove pilot air jet

do the o ring mod with wire

Thanks for all the info!

Use a 155 main jet,

EMN needle clip 3

45 pilot jet

2 turns fuel screw

Remove pilot air jet

do the o ring mod with wire

running exact recommendations and the bike is idle pretty well, was sputtering for a bit but adjusted idle control and worked that out. Climbs rpms fine but from closed to wot it bogs like no power. I did noticed by vacuum line does look a little kinked on top from the angle. Thanks again.

running exact recommendations and the bike is idle pretty well, was sputtering for a bit but adjusted idle control and worked that out. Climbs rpms fine but from closed to wot it bogs like no power. I did noticed by vacuum line does look a little kinked on top from the angle. Thanks again.

 

is it bogging when free revving or when your riding it..?

I didn't have time to test run it when I first put it on. Today I ran it and got these results. Goes first to 5th no hesitations. When clutching up in 3rd it bogs out a but. I removed the air box door and runs completely better. 3rd gear clutch ups have no more bog and 4th and 5th seem a bit beefier. I am going to test a 150 and see how it goes from there. Then possibly meet in the middle at a 152. Also have a idle that stays high at stops till I quick rev up. Thank you.

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