very jerky at low speeds and backfires at all speeds

[DRM57]

Hi new to this I have a yamaha gas cart (JG5-309307) what ever all that means. I have 2 problems 1) it backfires both at lows speeds and higher speeds.(somtimes extremely loud ) 2) its very jerky at low speeds any ideas of what to try?

[Larry1950]

I would start by putting in a new plug.