hesitation 1990 xt 600

[njenduro]

the bike runs great but she hesitates when crusing in second thirdc gear but when the give her full throttle she takes off with no hesitation at all she pulls great. I did rebulid carbs intakes gaskets orings etc. Any help would be apprecited, also air mixture how do you do it with out burning fingers and space is there a tool you use from yamaha?

[Wide Phil]

Weird I was going to ask pretty much the same question. My 03 600 E , in 2nd an 3rd feels like , when being held at a steady constant throttle, like it is going into the point wherethe bike is going to start to run out of fuel. Bang the throttle open and it pulls strong.
I have also noticed the bike smells very fuelly on start up but that could be just the choke I guess.
It also still has good mpg I think at 58mpg

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[njenduro]

Now I don't get fuel smell. Hopefully somebody will chime in.

[jjrider]

Yep that's one of the things my '88 is doing. Misses or acts like it is running out of gas, but runs perfect under acceleration. I have a set of Raptor660 atv Mikuni carbs that I am installing on mine( actually able to get parts for them and can adjust them easily). They bolt right on to the factory boot, need the atv airbox to carb boots and a motion pro twist throttle with cable. Just have to figure out jetting, hope it fixes the miss.

[njenduro]

Any help what to do with these carbs or suggestions to look for in the carbs

[jjrider]

The factory dual carbs need to be synced perfectly to start with (at least the ones on my 88) they did change some through the years though. The fuel mixture screw is the one area that with the atv carbs, I will have actual knobs to adjust easlily plus all possible sizes of jet(pilots and main)and multiple needle sizes/tapers and height adjustment that the factory doesn't. The needles control mid range.
The studdering I believe is from to much or surges of gas coming from the second carb but not the air to go with it , until you give it gas and open the second slide.
If you have a service manual, go through the syncing(timing of when the second carbs adds gas), there is just limited jets available and less adjustment options to fine tune them better. The newer models may be better than my older ones though.