G, RdPhil.
First let me welcome you as a new member and I am sure you will find a lot of interesting information and tips on the forum a great way to pass the time on a wet day Ha Ha.
Check the distributor advance and ****** weights inside the distributor ,make sure the weights Spring out and return all the way and the springs are not broken or stretched, also that the assembly is not tight on the shaft ,put oil in there .
Check the Strength of the Spark ,remove all plug leads and one plug reconnect to the lead and earth the body then crank the engine with the ignition turned on
You should see a nice bright blue spark if not ,first check the points making sure they are clean and have the correct gap .
If the coil is hot after a run ,Change the Condenser.
If after all of this check the carburetor ,first the mixture screw then the float level.
Thats all I can offer at the Moment.
Happy Days.
Hutch.