Troubleshooting

#1
I have a Coleman ct200u-ex and it has ran fine for a while and just recently it starting acting up. It would idle good for a few minutes but then cut off and if you gave it any throttle it would bog down and cut off. I replaced the carb and it started first pull and idled fine but as soon as I gave it any throttle it would bog down and cut off again. When I turn the idle up on the carb it wants to take off but as soon as the throttle is used it bogs down. Please help, thanks
 

Harquebus

Well-Known Member
#2
Sounds like typical fuel starvation.

Check all the pipes and hoses leading to the carburetor. Could be as simple as a clogged fuel filter. If there's a mixture screw on the old or new carburetor, turn it counterclockwise to richen the mixture. Most of these newer carburetors have succumbed to EPA regulations and are designed to run extremely lean, and then again, they are often not setup to run perfectly right out of the box and it is not safe to assume that anyway.

Does the engine have any modifications to it or is it stock, OEM, "factory condition"?
 
#3
Okay thanks, everything on the bike is stock parts except for the carb, I removed the governor screw that limits the throttle but that’s all that I’ve done.
 

SAS289

Well-Known Member
#4
How does it run with the back tire off the ground or the jackshaft chain removed? Does it behave any different? If so service the clutch.
 
#7
So, silly question, but what is your location? Purely asking for sea level and weather conditions. One small and easy thing to do would be to put the choke on part way and see if it takes throttle better than without. I do agree with @Tom S. on the ignition check up and valve adjustment first. I've had some stock spark plugs cause some strange issues. I always replace them with a NGK right out of the box.
 
#14
One other thing, check the air filter. If it's clogged the engine will starve for air.
p.s. pull your plug and check the color of the insulator, should be a a brown color, if it's black you have a too rich or oil fouling problem, if it's a real light tan, nearly white you are running way too lean.

Ditto on NGK, it's the only plug to use.

Side note, like has been noted, these carbs are set up lean, you add an aftermarket air cleaner and a header and you just made the problem worse. time to rejet the carb to make the engine happy again.
 
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