You need to flow about twice as much fuel for the same weight of air when compared to petrol.
The methanol will not colour the porcelain of the plug tip like petrol does, so you tune by discolouration of the metal of the plug.
You should use cadmium plated plugs and see how the cadmium burnd of the metal at the earth strap and the plug threads.
An ideal tune will show heat discolouration of the earth strap to about thr bend in th strap and will show heat to about 3 threads up the plug at the earth strap side of the plug.
You need fresh plugs for each test as once effected by heat, the colour won't return to original.
The threads are more effected by A:F ratio and the earth strap more effected by ignition lead, however each effects both to some extent.
Regards
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