Other 1989 honda xr100 not starting!! please help!

I have a 1989honda xr100, i bought it off a friend, it was running then but it was flooding out, i took apart the carb and cleaned it and the jets and the floats, still wouldnt fire. replaced spark plug and am getting a nice blue spark, but still not firing, i am getting gas to the carb, still nothing. i tried kick starting and bump starting and got nowhere. it didnt even try to fire with starting fluid. i seem to be getting compression because after about 10 kicks it starts to pop from theexhaust, i checked the timing and it seems to be right in time. i disabled the kill switch and put a little gas in the spark plug hole and it will not fire at all, im so stumped, any good ideas out there? the top end looked great too..
 
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I have a 1989honda xr100, i bought it off a friend, it was running then but it was flooding out, i took apart the carb and cleaned it and the jets and the floats, still wouldnt fire. replaced spark plug and am getting a nice blue spark, but still not firing, i am getting gas to the carb, still nothing. i tried kick starting and bump starting and got nowhere. it didnt even try to fire with starting fluid. i seem to be getting compression because after about 10 kicks it starts to pop from theexhaust, i checked the timing and it seems to be right in time. i disabled the kill switch and put a little gas in the spark plug hole and it will not fire at all, im so stumped, any good ideas out there? the top end looked great too..

First of all if its flooded, dumping gas in thru the spark plug hole won't help that. I would first shut off the gas, pull the plug and clear the cylinder by kicking it over several times, then install the plug and with out turning the gas on try starting it. If it starts or try's to start you have an issue with the float or needle and seat. Letting to much fuel into the engine. If it doesn't start then I'd try a compression test, it should be at least 150 or higher, if not you may be looking at leaking or out of time valves. At that point a cylinder leak test would be in order, basically with the valves shut at TDC fill the cylinder with shop air and if it leaks out either the intake or exhaust it's valves, if thru the crank case then rings.start out with these checks then get back here with your results.
 
i kno this was probly hella days ago but im just curious if u would do these tests with the engine mounted or pulled off lol..also if it was neither rings nor valves what would happen to the shop air
 
i kno this was probly hella days ago but im just curious if u would do these tests with the engine mounted or pulled off lol..also if it was neither rings nor valves what would happen to the shop air

It can be done with the engine installed or not, if properly sealed you'll see around 10 to 20% leakage, which is going to go by the rings, if the leakage is greater than that, either the valves or rings are not sealing properly. Just find out where the air is going, head gaskets can be found this way also, pretty easy to see as bubbles will rise from the radiator coolant.
 
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