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I have recently purchased a 2001 JR50. The man's son rode it around for several minutes before I bought it. Now it won't start. Here's my saga and I am looking for help.

1. It was running when I bought it and the guy's son even wrote it around for me before I paid him.
2. I accidentally left the fuel tap on when I dropped it off at our farm, and when I returned about a week later all the fuel had drained out, presumably through the carburetor overflow.
3. I filled up the gas tank with premix and it would not start. It wouldn't even pretend to start. The oil injection tank is empty, hence the premix.
4. I verified that the sparkplug is firing and replaced the spark plug because the old one was pretty dirty. No luck.
5. I installed a new carburetor today and it still didn't crank or even fire.
6. I took the spark plug out and kicked it over and noticed a copious amount of gasoline that was black shooting out of the spark plug hole in the cylinder head. So I thought maybe the rings are bad, or it is severely flooded.
7. I took the cylinder head off and inspected it and the piston and the cylinder walls and everything looks fine so I turned the engine over to bottom dead center and tilted the bike all the way forward up on the front wheel and poured all the gasoline out of the engine through the cylinder. I put the head back on.
8. I changed out the spark plug with another new one just in case and tried to crank it up with the same results. It doesn't even act like it's going to start, so I verified again that the spark plug is generating spark. The spark plug is somewhat wet but it's no longer covered in black fuel like it was before. No luck. It is definitely getting fuel and spark but doesn't even fire up a little bit.
9. That's where I left off. I'm not quite sure where to go from here.
 

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I would suggest the engine is flooding...either the carb needs attention or, if fitted, the reed valves are not sealing. Also check the exhaust is not clogged up and also the muffler. Most two strokes have a removable baffle and you can burn any carbon build up off with a blow torch.

Since you had the head off I presume you checked the exhaust port for carbon build up....if not that is another area that can stop the engine from breathing and thus running.

Good luck
 

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5. I installed a new carburetor today and it still didn't crank or even fire.
I wish I could help but probably not.
Only one wild guess:
Could there be a safety of some kind that prevents it from running when the oil tank is empty ?

Then, using the term "crank" the way you did will likely just confuse matters.
"Won't crank" means the engine won't turn over, as in it is locked up.
 

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Discussion Starter #5
Got it running. It was severely flooded. Just swapped the plug and held the throttle wide open and kicked it over until it cranked.

Thanks to all for their feedback!
 

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and kicked it over until it cranked.
SIGH. Old habits are hard to break.....especially when you don't try.
"crank" is NOT a substitute for "run".
You kicked it over (cranked it) until it fired and ran.
 
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