The list is long that can contribute to a hard start. Under primed, over primed, poor glow driver charge, poor glow plug, incorrect needle settings, incorrect idle gap setting, loose engine screws (head, backplate), etc.

If you have reasonably close settings on the needles and idle gap is .5-.7mm, then try this: fill fuel tank full. Remove pressure line from tuned pipe (that goes to tank). Blow into pressure line until fuel reaches the carb - blow one more second. Connect pressure line back onto tuned pipe. Connect glow driver, and hold transmitter while trying to start the engine. If you give it about 5% throttle (so throttle opens just slightly) when you pull the starter, it should fire right away. If you have to hold the throttle open slightly every time you start the engine, the low speed needle is too rich. Lean it in 1/16th turn increments until it starts better and idles nice/transitions to high throttle effortlessly and without a ton of blubbering and smoke.