You bike came with two different jet sizes, 155's in the middle carbs and 157.5's in the outers. You need to keep that stagger to get the bike to run right. Some jet kits (Dynojet and K&N and maybe others) use jet numbers that don't correspond to factory numbers so a 125 might be bigger or smaller than a factory jet number 125. Since you have the 155's buy two 152.5's and put them in the middle carbs and the 155's in the outers and try that. Many bikes come from the factory pretty rich on the top end.
Everyone's forgetting a solution to this problem that we discussed a month or so ago. The Flo-Commander offers many things, and one of them is much quicker mixture adjustment. You can make across-the-board adjustment without even having to remove the carbs. In fact, if you desire, you can mount the Flo-Comm valve outside the airbox and accessible without removing the gas tank. This would be great for drag racing, and changing temp conditions or as described here, altitude changes.
Yes, you're very right. But I can't afford to install it on my bikes. If you want to pay for it for me to use on both my bikes, I won't object. Not one Iota.
Until then, I'll just keep picking up a handful of jets at a time, and adjusting the mixture screws as needed. Don't think I'll ever spend the amount asked for a Flo-Commander if I go that route, even though I compromise the ut-most extreme in performance. I can live with a compromise like that.
I didn't do it, I swear.
And even if I did, what makes you think I would admit it to you?
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