Needing jetting done to jet

[big_champ]

Rebuilt my carbs (squeeky clean and new parts), modified my airbox, por'd the tank.  Didnt sync the carbs yet but did sort of worked the synch rod by ear.  I need two weeks before i have time to tune it.  Bike turns on and works good except, idling at bout 4000rpm even after playing around with idling screw and pilot screws.  Other mayor problem is terrible stumble when kicking gears up and plenty backfiring after easing off throddle.  Now before I go out and start planning stuff, i wanted to check with you guys, its probably my jetting right.  I put on 122.5 and 127.5 and 130 like the manual says to do, i dont remember in what order they were.  So I need to know what jetting you guys out there with a modified airbox have and what you have your fuel/air mixture  screws set at.  My elevation from sea level is 381 ft  / 116 m if that matters any. 
Thanks again guys

[Lucky]

go stock jetting on the mains & pilots, 135 on the pilot airs. (top of carbs)

Synq & pilot screw settings are critical to getting rid of the stumble.? set synq for best match at idle, not highest vacuume reading.? cap off the YICS while synqing.

the pilots should be turned in, one at a time, untill the bikes idle roughens up, then out till it roughens up, count the turns as you go.? set the pilot screw in the middle of theis range PLUS out 1/4 turn.

repeat with the other pilot.

if the bike still stumbles turn the pilots out 1/8 more & retest drive. these bikes will stumble normaly when stone cold.

if your still having problems, then check for a leaking YICS (you should anyway) or other vacuume leaks.

this is all assuming you have the modded airbox.
--Lucky

[h2olawyer]

As for the high idle speed, check for a tight or binding throttle cable or the choke (enricher) may not be closing properly.

H₂O

[Lucky]

i missed the comment about the high idle.. defenatly check for a leaking YICS & cracked hoses

[Lucky]

come to think of it, your synq is probably way off, that'll raise the idle significantly.  don't try to synq with the $4 manometer, & be careful with a mercury one, you might suck out the mercury...

you might want to try readjusting the synq with the bike warmed up & running with the initial goal of lowering the idle. you'll have to turn the sync rod just a bit to where the idle starts to come up, then lower the idle with the thumb (stop) screw in the rear carb.  you should repeat this procedure untill you have a warm idle of 1325 +/-25 rpm, & THEN attach your manometer.

--Lucky

[Extent]

Don't worry about using the 4$ monometer to get the sync right when mine were crazy out of sync, just takes a little extra prep.

Before you start the bike take the two tubes and place them on top of each other, then clamp them completely flat with a pair of pliers.  Hold the pliers really tight and start it up.   Then you slowly let off the pliers and watch which way it goes.  Adjust the sync to keep it under control and then let off the pliers a little more.  Just repeat until you've released the pliers all the way, do your fine tune and seal it up!  If you let them loose too fast just quickly kill the engine and waith for the fluid to settle all the way back down to the bottom and start again, and if a little gets in the engine it'll just smoke a bit and shouldn't hurt anythying. 

[Lucky]

The reason i didn't suggest it is that so many of you have sucked  the fluid out... ;D

It seems that you could also stick a couple of pilot jets in the hoses as well, that should smooth out the pulses too.

and new we can have a debate on stock vs high performance jetting for the $4 manometer  ;D ;D ;D ;D ;D

[zore]

I was forced to buy some jets at deals gap.  I put a 120 in the front and a 125 in the rear.  The only mods are the mac exhaust.  When I got the bike home, it ran far better than it did with teh 122 and 127.   It definetly has more power and has no stumbles.  It was still a tiny bit rich at the really high elevations as I had a bog when giving it a fist full of throttle.