KTM 50 SX help?!

Hello, I recently bought a 2008 KTM 50 SX for my daughter. I can't seem to get this thing running. I'm hoping maybe someone has a suggestion. It's getting fire... I put a new stator and coil on it and you can see it firing while holding the plug against the cylinder. It's getting fuel... the plug has fuel on it when I pull it to check. Also can see a little fuel down in the cylinder. I can't even make this things backfire while kicking. Very strange. It seems to have decent compression. I lack a compression tester here at the house for specifics, but it pulls and pushes through the spark plug hole while covering it with my finger fairly well. I'm at a loss at the moment. I've been through the carb numerous times. All jets are clear, float seems to be working properly. Slider seems to be functioning properly. I even tried another carb that I was given extra with the bike. Having the same results. Any help would be appreciated. Maybe someone has experienced this as well.... These little things are touchy.

It the timing correct? Jetting? New spark plug?

I was able to get it cleared out and firing now, Finally! But it appears to have some clutch issues. It just doesnt seem to be putting the power from the motor to the rear wheels. The clutch pads are new. The basket is old. It does not make the typical high rpm slippage. But after talking to the previous owner, he says someone told him the clutch basket was slipping on the shaft. Which doesnt make total sense to me because the clutches are on the splines of the shaft... the basket spins freely on a bearing that is on the shaft. As the pads expand, they come in to contact with the basket which has a gear on the back sync with the drive gear and shaft, which spins the front sprocket. 

Look up the term lapping, and lap the shaft.

Check the gear that is driven by the clutch basket.  The key can strip out and it will turn as well.

 

Kdub is saying the tapered fit of the clutch hub on the crank shaft could be bad, lapping it will repair the fit.

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