Zongshen 250cc dirt bike wont start

hey guys,

 

i'm new here i hope i'm posting this in the right place.

 

i got a Zongshen 250cc dirt bike given to me by a mate and it was apparently running fine before it was put in storage for just over a year, i changed the oil, cleaned the filter and put fresh fuel in it but it just wont kick over any ideas?

Hi, sounds like junk in the carburetor and fuel system, including all hoses and the tank.   Drain out what gas is in there, then flush tank and fuel lines with fresh gas, use about a gallon, just flushing it out, also use some carberator cleaner, the spray on kind, in the tank, mix with a little gas and let it flow throughout the fuel system, this can be done by removing the bottom of the carb float bowl nut.   Then flush it again, with about half gallon of fresh gas.  Go put in highest octane gas you can buy, and try again.   But first be sure the carb has been cleaned completely.  It might need to be cleaned again after you do get it running, because more junk works its way through the fuel system. After about three times all should be normal and well.    Ride it for a while, do not go anyplace far from  home, because usually junk will clog the pilot jet again, making it stall and run bad at low RPM, when this happens you must repeat the clean out process again.

  Sometimes a wire gets grounded out too. Check for that.  Make sure you are getting spark.  remove plug, leave cap on it, place plug against cylinder head, kick through the starter and you should see a WHITE BLUE colored spark, if its just white, and small, your loosing some energy along the way. Back trace for shorts. 

Remember its a must to completely clean out the carburetor first, then flush system.  Instead of completely cleaning the carburetor again, just turn it sideways in manifold, remove the bottom of the float bowl, and spray it three times with carburetor cleaner spray.  (gum out, or some type of auto carb cleaner). ... you might have to do this at least three times.

Good luck..  and if you park it over 2 months, put GASOLINE stabilizer in the gas before parking it, and let it run the gas out of the lines by shutting off the fuel supply while its running and let her run dry.  Its ok to leave gas in tank, if you have stabilizer in it. 

Good luck

GARY

thanks Gary, i gave the carby a good clean and flushed it all out  and it started though it not running to well its the idle seems very high and the when give it a bit throttle it starts choking and dying out. 

 

once again thanks so much for your help is greatly appreciated relatively new to the sport and i'm very keen to learn.

thanks Gary, i gave the carby a good clean and flushed it all out and it started though it not running to well its the idle seems very high and the when give it a bit throttle it starts choking and dying out.

once again thanks so much for your help is greatly appreciated relatively new to the sport and i'm very keen to learn.

I just sold a bike with a zongshen cb250 motor that had a very high idle when I got it. I tried letting out the air screw and opening up the fuel screw a bit which helped as they tend to run lean but it still idled high I had to polish and lube up the carb slide to solve the problem fully. There were some burrs causing it to stick open a little to much. You can also try moving the needle clip up a notch if your slide isn't sticking and make sure your needle tip isnt bent causing it not to seat right.

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