There is a better way, says Garry Simkin, who well knows the manipulations needed to time the magneto(s) on an air-cooled car.
He writes:

It seems like forever that I have used a cigarette paper to determine when the points open by way of setting the ignition timing of my magnetos.

As with many things in life, there is a better way. Recently, noted vintage car restorer and Mk 9 Cooper Norton owner Grant Cowie introduced me to the ‘Inductor Magneto Timing Light’.

By connecting the two leads to the magneto, and turning it, this device measures the inductive current, not continuity, to determine the exact of position of the points opening. This causes lights to indicate points opening and closing, but most useful is a rather loud beeping noise when the points open. Having the noise is great when you have your hands busy rotating the magnetos, and are trying to wrestle the cigarette paper while trying to get the drive sprocket onto the taper all the while tightening up the nut. It may be fine if you are an octopus, but it’s a messy and not entirely accurate business.

In his book Tuning for Speed, Phil Irving has mention of a method using a battery, light bulb, leads etc, but this also requires you to remove the centre screw. With the Inductor system no dismantling is required. It’s an all-round fantastic device which was primarily designed for timing aircraft magnetos. You can contact Grant Cowie at his Up The Creek Workshop on (03) 5470 5526 for more details and can check out his workshop and some interesting cars at www.upcreek.com.au

For magneto service Garry is happy to use Chris Zoch at Harrington, NSW, 0424 011 767.

Another cute little device was illustrated nearly a century ago in Motor Cycle magazine and it might be useful to those who like to rebuild their own crankshafts. Most of us with a lathe would put it between centres and then use a dial gauge to check the concentricity of the flywheels, but this little device might have a use if you are one of those people who might find themselves rebuilding their engine at a race meeting as people, including the editor, once did.