crash! can't figure out why?

My roommate has a 70 bonneville t120 thats in original condition. its wore out here and there but it looks pretty good for the most part. we ride together often. My norton has been giving me fits getting going so i was on another bike behind him. his bike was running fine, idling fine, sounded ok. After making a stop at a stop sign, we began accelerating and his bike reved all the way up, spun the back tire out and dumped him right there in the street. Mirror got smashed, footage rubber ripped apart, and the choke lever is broken, but all and all, no real damage. his bike went back into the garage and he began to fix somethings on it while it was out of commission. The carbs are clean now and he kicked it over and it went straight to redline again. all cable routing was checked, valve clearances checked, carbs clean. thoughts?

doesn't matter if its in gear or not, its WOT as soon as it fires. again, ran fine until it happened, now I'm not sure what to do

You say the carbs are clean but when at start up are the throttle slides at the bottom? if they're not she will rev out :evil:

Sounds like a stuck carb slide

It certainly won't "go to red line" if the throttle slides are sitting at the bottom.

It's pretty basic.

ill look again whenever I'm back over there. they were at the bottom when i looked at it, seemed to return alright when i checked the throttle opening and closing. i was just seeing if anybody had anything else that i hadn't thought of already. strange that it would return normally and then stop randomly. ill update when i check again

If the insulating spacers (reddish-brown, look like thick gaskets) are missing between the carbs and the manifolds the carbs can get hot, the bodies distort and the slides will get stuck open.
I can confirm this from personal experience...