i recently purchaced a Roketa RTH-250x
heres pix





so far ive had to clean the carb sence it wouldnt idle and it kept leaking fuel after shut down... i cleaned it and it idled and ran great for bout 20min then started running bad under throttle so i pulled it back apart and cleaned again... now it runs fine under both...

now the problems im getting the chain jumping... looks asthough the P.O. possibly flipped it cuz i see stress marks in the plastic and the rear swing arm i belive is bent cuz axle looks straight but the sproket in the rear is tweeked and is grabbing the inside of the chain so i might be refabbing the swingarm...

also im getting some backfireing and after like 1/4-1/2mile of hard throttle its like it drains the bowl and just looses everything and falls on its face then dies sit a sec and it will restart and your good to go...

any ideas on anything guys thanks

 

Welcome to the forum Brinkmeyer!

Good deal getting it to run...

For the jumping chain... try and see if the engine sprocket is inline with the rear sprocket... might have to remove the chain and lay a straight edge (3' ruler would work) on the side of the sprockets.. Also check and see if the chain and or sprockets are worn out...

May have something in the gas tank obstructing flow.. could be the tank isnt vented... try riding it with the gas cap loose...

 

the rear sproket looks tweeked a lil... the rear axle looks like its mounting a lil crooked to the swingarm causing it to grab the inside edge of the chain. sprokets look fine as well as the chain old but in good condition...

ill have to try the loosend gascap it has the vent hose on top of the cap i didnt see anything in the tank when i looked bfore i filled it up and i added a bottle of that "Start your engines!" dad said its good stuff and he uses it in his quad to clean everything out and takes water out of gas and everything else...

 

My bike has the same problem where full throttle runs for a while will drain the bowl.
I have cleaned my tank by hand, and cleaned the mesh protector thing.
I think it's just the fuel line, it's kinda small. Not quite weed eater line, but still a bit smaller than regular 1/4 line

 

I've run into this problem twice on two different quads.

Pull the fuel line off at the carburetor and see if fuel gushes into a container for at least several seconds. If it gushes for several seconds your fuel delivery problem is inside the carburetor. If it diminishes to a trickle the problem is before the carburetor.

In my case both times it was the fuel petcock value that was bad. One was bad from the factory (blocked passage - I drilled it out), the other was due to the fact that the dealer installed a water shutoff valve instead of a gasoline compatible valve. The neoprene seal inside swelled up with contact from gasoline and blocked the fuel passage way.

Other possibilities for slow trickling fuel delievery: Plugged fuel filter, Plugged gas tank vent (as MWQ pointed out earlier), plugged fuel line, kinked fuel line, Plugged gas tank output feed lines.

 

well when i cut off the quad i HAVE to shut off the fuel or the carb will drain the tank i think carb is probly shot it will let the tank drain if i dont shut it off so yea...

last time i rode it the damn fuel line from the tank came off!!! only way i could get it to the house was to shove the line back into the shutoff and try and make it up the hill by holding the line in and trying to drive too! i made it but the little metal sleve that the line goes over came out of the shutoff valve so looks like im going to have to get a new fuel shut off and a new carb and try and re allign the rear end

thanks for the info guys