2001 XR100 sputtering under load.

I have a 2001 xr100.  It has been sitting for about 2 years.  I had the carburetor cleaned.  It will start on the first kick everytime, idles smooth, revs smooth in neutral and with the clutch in.  But once you put a load on the engine, try to take off to ride it, it spits and sputters and will barely run.  Anyone have any ideas for me???

Thanks  

Nope sorry man, I had one but this never happened to me. Im sure some one on here will be able to give you the helping hand you need. They always have for me. Oh and welcome to the forums.  
Adam
2002 XR 100R
2003 RM 100

If it has been setting for 2 years ,,,clean the fuel lines, air filter and use a new plug , if you haven't already.  
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"Every time I start thinking the world is all bad, then I start seeing some people out there having fun on motorcycles. It makes me take another look." -Steve McQueen

Was the main jet cleaned, Sounds like a goober or something has made its way into the main jet. also as Daggit said check the fuel filter(in the tank) and the float needle. I will bet the problem is there
Tim  

check ignition strength. try gapping the plug a bit closer to see if that helps at all. if closer gap makes it a bit better you should look into replacing or re-winding the stator. at least start with a new spark plug.  
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Being fast is 90% rider and only 5% bike the rest is luck

Thanks for the reply.  I did have the carburator/jets completely cleaned, and replaced the fuel filter in the tank.  Still no luck.  Seems like the sputtering clears up once you get it opened up, but it is really bad in lower gears on take-off.  Any other suggetions would be greatly appreciated.

Thanks again,
Tom