[Steeveedee]

A charged battery is 12.6V. 11.3V is dead. Whether or not the alternator was good before you pulled the battery cable off while it was running, you probably fried it when you did that. It also sounds like your carb needs work. It's quite likely that the accelerator pump is worn out or the transfer circuitry to the jets is clogged. That can also cause a backfire due to a lean mixture. And you need a clutch, if the adjustments are maxed out. Good luck!