Edit: oops.. had not read all of the above... below is about carbys: Make sure you adjust the float level... with the carbs on the bike: with bowls off, hold the float gently and turn on the gas. The idea is to have fuel shut off completely when the float tops are "level", or parallel to the carbs. As the float drops, the fuel should start to flow. TIP: I have done the above, OFF BIKE, by simply using some (unused!) fuel line which I stuck in my mouth to blow air, and holding the carbs up at eye level while I moved the floats up and down. You can easily feel/hear/see the proper "float level"... The adjustment is done by gently bending the little tab that actually pushes the float needle up. Once you get it adjusted, then try it "live" on the bike... if you still are getting fuel overflow, then chances are that the floats are sinking. Those foam floats can be nasty looking and orange and still work fine, but they should not have absorbed ANY fuel. If the leaking happens intermittently, it is likely that the tab/float-needle interface is not sliding, and it could be either a worn/cruddy tab, or a bad needle. Of course, replacing both needles and both floats should get rid of any hardware problems! ($$!) Good luck! Further edit: your car battery/jump should provide enough juice for ignition system, if not turnover by starter. Are you sure you have your switch "on".... those Slash 5 "switches" can be pretty funky! If you can, just make sure you are getting 12v to the coil when the switch is "on"... and then the next thing to check is that your points are opening/closing and not shorting.