Engine isn't capable of moving the go kart

[Lavastar889]

So we recently got this really broken go kart for free, we replaced the ignition switch, carb, fuel filter/line, and the battery(which acts weird and barely gets the job done), and we got it to start and run, but when we attempt to drive it, the engine gets to really high revs before it starts to move slowly, and can't even push itself up a 4 degree slope and bogs when you got to full throttle. The weird part is that it's pretty easy to push by hand, and even when jacked up without tires, it still needs to get to pretty high revs to move the axles. The engine was definitely never replaced, so that's off the charts, and before the dude we got it from left it outside for 4 years it ran just fine.

Specific model of go kart: dong fang DF200gka

 

[Denny]

Sounds like a worn belt or frozen clutches. Time to take stuff apart.

 

[Hellion]

...and the battery (which acts weird and barely gets the job done)

Consider putting it on a trickle/float/battery-minder-charger to keep it topped up at all times. Motorsports batteries don't really last long.

the dude we got it from left it outside for 4 years it ran just fine

"Ran fine when parked".

It's a Chinese buggy (love the DONG name!) and they are problematic BUT it sounds like it was rode hard (enjoyed and abused) and then put away wet (wet, getting rained on). You have your work cut out for you, got a parts/owners manual for it?

 

[Karttekk]

Maybe talk to someone here, they should be able to suggest where to start.

Dongfang Jaguar Adult Go-Kart Buggy DF200GKA, Big Bore 200 PowerStroke

The Dongfang DF200GKA is the top-of-the-line best made GY6 class buggy ever built

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