My 125cc TDR Thumpster won't start

[mark125]

hey dudes.... this is my first post.... i have a 125cc TDR DUCAR GENERATION II ENGINE, 4 Stroke HIGH PERFORMANCE SingleCylinder, Air Cooled, Unleaded Petrol Only....
bla bla thumpster and Willy took it ridin' and now it has trouble starting.
i put new fuel in it and a new plug... it still has trouble starting... and when it does it idles ok but it seems like it's running rich and backfires... then dies if you give it too much.... seems like the timings out? this is not a choke problem...
....its only used 3 tanks of fuel from new.
....any ideas? thanks for any advice....

 

[thump*140]

more than likely valve clearances.... it's a very common affliction with pitbikes... run through the thread below, and do your valves, see if that helps....
failing that, the crappy Fakuni carby has probably shat itself...
http://www.miniriders.com.au/motor-tutorials/24965-how-set-valve-clearances-horizontal-engines.html