kwakninja

Hi, I bought a winter hack, a lil ol' dt50 on an 04 plate. The problem is that when I try and give it some, it just dies!!!! Its fine up to half revs and detests hills (which is crap for a crosser lol!) I dont know much about the bike, I have been told it has a de-restricted exhaust fitted, the guy thinks its an 88 mm main jet (but he cant remember!) What size should be in there as standard and what size is recommended? Also, does anyone have an 'idiots guide' as I dont know how to change jets :-) One final (stupid) question....my mate tried to tell me its a 2-stroke, but I didnt think it would be as its a 2004 model???? Sorry for the long thread, hope some one can help me :-) thanks guys