Needing some help bad spark issue and will not turn over.

[beck125]

.ok im at whits end with this 400ex, its an 01 i beleive, but anyways last winter i rode the piss out of it, but it was also on a fresh rebuild, anyways i parked her in a covered garage covered up treated gas, and now it will not start, i changed out the plug, i changed the stator, i tryed another cdi i used a different coil it will not start, it chugs there is compression, i have not ran the numbers on it yet, but the spark plug is sparking but apparently not enough. . to kick it over.. needing some help guys, i also changed out the fuel have cleaned the carb, the carb spits out fuel once you crank on it for a while as in flooding the carb out but i pull the plug and it has fuel on it.. i am leaning towards the valves i will pull the covers off and let you guys know, also checking the compression tonight, im out a quad and this is not good! thanks
jordan

[riotact]

I would drain out all of the old gas,clean out the filter and petcock,fill it up with fresh gas,and start there.If that does not work then i would clean out the carb really good.Usually if you have spark and it will not run,its a fuel issue.

[riotact]

Or to verify that it is a fuel issue,take off the airbox and hit it with some starting fluid.If it fires up you know what the problem is.

[beck125]

forgot to mention,.. i tried starting fluid as well..

[sc400ex_rider]

tight valve check your lash. check and do a compression test. also make sure the battery is charged. if no one messed with it it should run on starting fluid. all you need is fuel, spark, compression.

[riotact]

Forgot about valve lash and compression,but if it ran good when it was put away and then would not start,I'm leaning towards a fuel issue since it does have spark.