I’m based near Mansfield and am quite handy with the spanner’s and diagnostics. Throw away any old fuel if it’s still in the tank. Make sure the fuel tap allows fuel to flow, the filter if still there may be blocked. The carb float needs to be free and not stuck in the up position. The float needle needs to be free to allow fuel into the bowl and actually shut the yellow off when raised by the float. This is a bit like the toilet system. Remove the spark plug and ensure there is a gap (thickness of a thumb nail will do for now) refit the plug to the HT (high tension) lead cap and rest with the plug metal body touching the cylinder head fins. Make sure bike is in neutral, use kickstart to spin engine over. You should see a lovely fat spark at the plug gap! If not then the contact breakers may be stuck or not opening, I am assuming the bike has not been upgraded with an after market electronic ignition kit. If you have a spark you nearly there. Fuel, air and a spark, now all you need is compression. Refit the spark plug and press down on the kickstart with one hand, leave the plug lead off! You should feel good resistance, if the kickstart turns the engine easily then compression may be poor or the rings may be stuck in the ring grooves in the piston. Crankcase seals if worn will produce all sorts of starting and running issues. That’s about it for you to try should take 20-30 minutes. Dots had alloy tanks, if yours has a glass fibre tank then you have more issues to consider. If your Villiers engine has an alloy barrel and most did from Dot the you must be really careful that if working on the piston the rings will be plain and NOT chromed. The cylinder in alloy barrel was chrome plated and chrome on chrome will tear itself apart. The Villiers engine may have an iron barrel which can take the chrome top ring no issues. Hop this helps and you have some success.
