You definitely have to be up to the task prior to mail-ordering one of these. It's the price you pay for paying ~25% of what a name-brand ATV will cost you. I like to tinker and wrench as a hobby so it's not a problem for me. Yes the manual is absolutely worthless. Like so many things imported from China (form over function), the manual looks the part, but is useless. A 40+ pg paperback with my specific model # stamped on it, but the whole thing is just safety guidelines, precautions and warnings. There are a few pictures, but none of them fit my machine. It does recommend 15w40 engine oil, but not how to change/check/add or even the volume needed!! My machine came with a setup DVD. It's pretty funny. A couple of Chinese dudes in dollar store white gloves just outside the factory door demonstrating very basic unpacking and setup of the various quads. No text, no audio. In reality though, if you've got basic mechanical ability, much of it is self explanatory. It even comes with the tools needed for setup and basic maintenance. Yes, the throttle lock screw is the long Philips head screw with a hex lock nut. Basically screwing it in further prevents full range of the thumb throttle. It works well. The front drums and rear disk brakes are awesome. And the Chonda CT90 (107cc) is a really sweet little engine. Yes the 12V battery is the size of 2 juice boxes. You pretty much have to use the included trickle charger on it. Mine fires right up in temps below 20°F. Whitearrow, there are sites dedicated to Chinese ATVs that are awesome resources. I'll PM them to you.
Joel