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brand new TT FCR 39mx jetting?

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Hi Gurus

the instructions say the settings for open pie which i have, but nothing as far as other mods?

do i need to adjust for the big bore and cams that i also installed? or just go with the settings on the directions.

im at sea level also. 2007 S model

thx in advance

kevin

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Use a 155 main jet......the other settings are the same

 

155 main jet
200 main air jet
EMN needle
clip 3
45 pilot jet
remove pilot air jet
2 turns fuel screw
o-ring mod

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Use a 155 main jet......the other settings are the same

 

155 main jet

200 main air jet

EMN needle

clip 3

45 pilot jet

remove pilot air jet

2 turns fuel screw

o-ring mod

 thx very much craigo :thumbsup:

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Use a 155 main jet......the other settings are the same

 

155 main jet

200 main air jet

EMN needle

clip 3

45 pilot jet

remove pilot air jet

2 turns fuel screw

o-ring mod

hello again

 

everything was done to your specs exactly. never had the bike running with the big bore or cams before the install. got it running pretty well, or thought i did. took it for a 30 min ride for break in, various throttle the whole time, with a couple full throttle pulls at the end.

 

problem im having is there is a substantial bog from 1/4 throttle with roll on or a quick snap. took the side cover off to see if that helped and it did just a little bit. soooo, i must be rich right?

 

thats where my knowledge ends. would i need to change the  155 MJ to something else? the carb came with the EMR needle installed and i swapped to the EMN as instructed, could this be the issue? pilot curcuit seems fine, idles and starts pretty good, other than the choke is a pain with the big gas tank but managable.

 

i do live right on the ocean but ride up to 2000 ft, but all testing was done right around sea level.

 

thx in advance

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1979ford , the FCR/MX is a pumper carb , meaning it will squirt neat fuel down its throat when you twist the throttle . Now if the timing of this squirt is out , it will bog , so it is crucial that it is adjusted correctly for proper performance . Find the adjuster on the pump arm and turn it a half turn , either in or out and go for a ride . The only way to tell if the timing is too fast or slow is to look at it when it pumps , this requires the carb to be pulled out of the bike . So just persevere with it and adjust the AP squirt untill it comes good , and it will , it will just take some fine tuning , greg

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Turn the AP timing screw in 1/2 a turn to delay the squirt...

Make sure you have a tight fit with the o ring on the ap arms so they are not separating...I prefer to use wire..

Edited by Craigo 485sm

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1979ford , the FCR/MX is a pumper carb , meaning it will squirt neat fuel down its throat when you twist the throttle . Now if the timing of this squirt is out , it will bog , so it is crucial that it is adjusted correctly for proper performance . Find the adjuster on the pump arm and turn it a half turn , either in or out and go for a ride . The only way to tell if the timing is too fast or slow is to look at it when it pumps , this requires the carb to be pulled out of the bike . So just persevere with it and adjust the AP squirt untill it comes good , and it will , it will just take some fine tuning , greg

 

Turn the AP timing screw in 1/2 a turn to delay the squirt...

Make sure you have a tight fit with the o ring on the ap arms so they are not separating...I prefer to use wire..

ok i will try the AP adjustment. i am now back in camp "working" for 2 weeks so it will have to wait till i get home.  thx again

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