I'm having the same troubles, didn't know a thing about the parking brake safety gizmo, go back out to the bike, still idling (that's about all it will do) and what do you know, the parking brake is on!. I release it and hit the throttle and it sounds like a new one. And to think I've had the carb off today, checked the valve clearance and put in a new plug to just to find out the parking brake was on, and causes it to stumble above idle.

amazing....Thanks

 

I have slightly different symptoms but perhaps the same problem? Sporadically, I'll be going along and all power will cut out as if the ignition were switched off. Pull the clutch in, and it instantly starts running again. Sometimes it'll happen a few times in a minute, other times it runs beautifully for the whole ride. I've never had issues getting revs above idle (on this Warrior anyway), although at times idling along, it hesitates a bit once I give it slight throttle.