Short history: bike had almost no compression, cylinders were out of spec, so bored out the jugs, new pistons & rings and did a valve adjustment because this too was out of spec. Tested compression, had around 140 in each cylinder, which I'm told is normal for a fresh engine til the rings seat. Carbs had been rebuilt about 2 years ago with Dynojet kit, 112 main jets. I started the bike, balanced the carbs, revved it a few times, made sure nothing bound up, and took it for a 10 mile ride, being careful not to exceed 4k rpm. I let the bike cool down, then went for another ride. Same routine, let the bike get warm for a few minutes, revved it s few times to make sure nothing was stuck and rode off. The idle seemed slightly higher than I had set it earlier. About s mile later, the bike wanted to rake off on its own, with no throttle input, I had to turn it off at red lights just to get home. The plugs were black, so I dropped the needles one clip. The next day, bike started, idlec fine again, and revved freely. But again, upon riding, revved up hard. I actually turned the throttle backward to try to "over close" the slides, and it worked. Inspected the plugs, they now looked normal color. The idle screw isn't even touching the throttle cam. I let it cool for a little while, then started it and it raced again.I immediately killed it to not damage my fresh cylinder walls/rings. and I'm going to start it again today, I expect the same result. Any thoughts?
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