I just bought a 2003 wr450 that has been sitting four the past 4 years. I bought a new spark plug and cleaned the carb and jets. I kicked this thing all day and only got it started 4-5 times but couldn't keep it running. The electric start doesn't work. I've read up on in and was told by the previous owner it is z factory defect in this year and model. Is there a trick to stating this thing. Every time it did start, it was shortly after I messed with the red knob on the bottom of the carburetor. I think its the hot start knob. But I think I have a jot start lever. I don't know. Any help would be great. Thanks.

Fresh petrol? Charged battery? Cdi needs a good voltage some times. Too much choke? Try starting on 3/4 choke and as soon as it picks up push it back in nearly all the way?

Have you tried bump starting it?