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Question concerning the air jets on the Flat Slide FCR Carb

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I was doing some maintenence on my carb adjusting it for the cold weather we were having here in phoenix, I have a friend that changed the air jets on his 250f and it seemed to have helped his throttle bog quite tremendously, I have a 98 YZF 400 and i was wondering if i did the same would that quick off the bottom snap come back if i possibly changed these jets around. The two jets are stock, a 100 and a 200. Any suggestions or concerns would be greatly appreciated, also for further information i had done the bk mod for the older fcr carb like mine so just thought i add that i have moded the accelerator pump to help with the problem.

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Going to a smaller maj will richen the mj, larger maj will lean the mj, with a 100paj you should have a 48pj and the acv removed. Pilot air jets have a simular effect, but need to be balanced with the correct ratio of air to fuel..with this rich of a pilot (assuming you have a 48pj) you should have a bog!! I would suggest using jd's kit, or find the jetting Q's thread and read it..:cry: Oh....on my YZ'ed 99WR400 was spot on perfect with no bog with a E_N needle..160MJ..160MAJ...40PJ...75PAJ..70SJ at sealevel. At 6000 feet+ and above 70F..E_P needle..160MJ..160MAJ...40PJ..75PAJ..65SJ..Nothing else changed but the fuel screw, adjusted to meet conditions. With the JD blue needle year round on clip three, 65SJ, FS adjustment only all year..No more removing the carburetor to change the needle and starter jet..plug and play :cry: Thats why JD's needle is in the new 450, more time to ride!!:cry: IMHO of course..Good luck and you don't have to live with a bog..:cry:

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