how does it run once you fire it up? if you do pull out the plug have a look and it will tell you what the jetting needs. Otherwise it may just be a charachteristic of the bike. I have an xr 250 and it started great when i first got it, after a few years it wasnt so pleasant. What works for me is i upped the airflow by drilling some holes in the air box and slapping in a new uni-filter. Also i had to be more patient with the start-up procedure. By slowly (turning over not starting) kicking the bike over 4 or 5 times to get everything in order (With the choke fully out) and then finding the compression stroke i kick it once hard and it now comes to life first kick.