terkarat

Check your wiring on the bike. I had a very similar problem on a rev3 I had. Every time I popped a wheelie on the bike it would cut out on me. It was so strange and I couldn't work it out. It turned out that it was a frayed wire up near the headstock that was shorting on the frame, causing it to stall immediately. As you probably know Betas are renowned for poor electrics as well so its worth checking. Hope this helps.