I have a thorspark on order, due later this week. Glad to hear it’s a good thingMy 229 works OK, petrol taps do not leak (they are new). I gather most of them leak. I am not surprised as 70 years old. I will fit the Concentric at the weekend. Going back to main jet sizes, my 229 also has a 200 main jet so I am going to try that first. On the subject of the mag, I have fitted a Thorspark coil ignition from Sussex motorcycles. The unit fits inside the mag which does not need to be removed. You will have to find a place to fit the coil, I have fitted mine on the engine support next to the battery. You will also need a switch so it can be turned on and off. I made a bracket to fit in existing holes in the rear engine mount for the coil and the switch. This unit uses very little from the battery. I have a gel type battery in a dummy case (like most people I suspect).
(Shared for amusement factor)
Also have a gel battery on order - should fit in the exide fake case. Found a convenient seller on eBay - who messaged me last night to say that they sold it to me without vat (they usually sell it to mobility carriages) and that I should send them my disability certificate to prove my right to the exemption ! Harrumph ! I’ve asked them to sort this out. Presumably they’ll send me an invoice for the difference