ORIGINAL: Craig 01
Hi Greg,
If your using a known good plug and your problems have only recently started,which it sounds they have,check the carb regulating diaphragm is soft/supple and not deformed/stiff,whilst your at it check the pump diaphragm and flap valves are supple and not deformed as well.
Craig
+1
Carb might have dried out internally, and a rebuild kit might just be the cure.
VVRC -or- TBM should have them, ask.
My old DL50 starts and runs just fine.