Think your issure is that battery was designed for a UPS, not as a power soure are a starter. I tried batteries from a battery store, not good results. The price is great. Able to start your engine, questionable. Wasn’t designed to be rattled around in a kart. Very short life cycle. Comet lists an orginal replacement battery. It will only be heavier on your wallet. But it will turn over you engine and it will last.
I think you have a bad battery or a poor connection somewhere in the system. I have a 7 amp hour version and it works just fine on my leopard even after months inbetween sessions as long as I disconnect the battery during storage.
I have had good luck with ups batteries when the Leopard charging system is maintaining 13+V. If it drops below 12.5v battery life suffers. Double check charging voltage before replacing. <span style=”color: #333333;”><span style=”background-color: rgba(255, 255, 255, 0);”>