I like my ruttman bike but have not been able to properly enjoy it for quite some time due to the engine (predator 212) always giving me issues. I've had a couple of ongoing issues come up that I have ironed out however for almost a year it has had the same issue that I've been to ignorant to know how to fix. Once it's warmed up for a couple of minutes, if I give it anything more than about 3/4 throttle it will shut down once I let off. It will continuously run fine at 3/4 and above as long as I leave it but once I let off it poops out. It doesn't do it when I'm putting around on it at a slower pace so I have no idea what the problem is and it could very well be something easy that I haven't tried yet. If it helps to point to anything it has had some "back firing" issues in the past - maybe timing related? I'd be willing to get a new engine if I have to but I'd rather work with what I've got until its craps the bed.