Starts great, runs ok, but tops out at 80 KM/h

xs400newbie

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Hey all,
The XS400 has been stopped for some time. We routinely start it up but yesterday was the first time in a long time I actually took it out for a stretch. The acceleration seemed a little sluggish at first, but after about 10KM of riding, it seemed to improve, however I don't think she's got much more than 80KM/h top end, and it could only maintain about 60KM/h going uphill. Is it starving for fuel? I'm going to take the carbs out again but I doubt they're clogged up as I cleaned them recently. This is an 81 Xs400 special so the timing is electronic. The floats are plastic and there seems to be some debate as to the correct float height. The plugs were changed recently.
She starts up fine and idles fine, but doesn't decelerate quick enough I find, so that when I'm changing gears, the revs are a bit higher than they should be. I sprayed carb cleaner around the carbs while it's running but no change in idle. We did a valve adjustment recently as well. The only thing I haven't done is properly balance the carbs, only a bench balance. Where do I begin?

Thanks!
 
Compression test results on cold engine:
Left: 145 PSI
Right: 155 PSI
The right side looks to be running rich. The left plug looks tanish, leaning towards white a bit.
 

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So I pulled the carbs. Right side main jet completely clogged and left side partially clogged. Float height seems to be 19mm. Remember these are the plastic floats. I read somewhere that it should be around 22mm? Can someone confirm?
 
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