mikuni carb set up

My new mikuni pumper will be here any day and i heard they are hard to jet if anyone has one and may be able to steer me in the right direction as far as jets that would be great! i have an 03 xr650r with a white bros heater and E series S bend can. the intake boot is opened up but am still running stock air cleaner and screen i live at sea level and do most of my riding between there and 2000 feet. i;m just hoping to be able to order jets that are close so i can ride the bike right away. I have no idea what jets will come with the carb but i am sure they will be way off

Thanx

The bottom and top jetting is easy. It will be about 20.0, 22.5 or 25 for the pilot. The main will be 137.5 maybe a 140 the hard part is they leave the Harley air jet in some of them .09 or 1.0 and the XR650R runs better with a 1.2 air jet. I found that a Y-4 needle jet and a 9dhj-1 (this might be the wrong number I'll have to look) needle worked best middle clip

http://xr650r.borynack.com/

Some mikuni stuff at the bottom of this page

http://www.borynack.com/Bruce/XR650R/HorsePowerMods.htm

Is this info for the 680? i am planing on keeping the pig a 650 until i blow her up. i will order these parts tomorrow if they don't have them in stock. thanx alot this will save me a lot of guessing and i can get rite to the fine tuning.

hey, I have a 2002 XR650R with a TM 40 carb and I am trying to figure out jetting. I live at 7700 feet in Colorado. I have the stock exhaust with power up tip. I have a K&N filter and opened up air box. Any help would be much appreciated. I am going to get the air jet in it soon.

Thanks, Morgan

No the jetting is for a stock XR650R but, leaner for your application. A place to get close so, you can zero in on tuning it right.

hey, I have a 2002 XR650R with a TM 40 carb and I am trying to figure out jetting. I live at 7700 feet in Colorado. I have the stock exhaust with power up tip. I have a K&N filter and opened up air box. Any help would be much appreciated. I am going to get the air jet in it soon.

Thanks, Morgan

20 Pilot should be close but, 22.5 might be better with a 1.2 air jet. Y-4 needle jet. What needle do you have? 135 main.

I have the 9DJY4-98 needle. I haven't checked the needle jet but it is the one that comes with it. I have a 1.3 air jet and a 20 main. I actually got it running pretty well last night but I had to retard the timing of the accelerator pump to get it right. Any help with the pump would me much appreciated. Thanks, Morgan

I ran the pilot a little ritch and the pump late.

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