ORIGINAL: downunder
For Dar's benefit, it even shows that he's correct in saying that adjusting the mixture has an effect on the ignition timing because the colder plug always can be set leaner for peak revs. I'll admit I'd reserved my opinion on this until I had another look at the column for needle settings on that site just a moment ago. There you go, I'm willing to learn
Brian,
I am willing to learn as well.
...But when I am sure that my understanding is correct, I do give it my best shot to convince, as you would too, I believe.
This would mean using too hot a plug will necessarily increase the engine's fuel consumption, but not only that.
Since the position of the high-speed needle affects the mid-range as well, maybe when an engine is using too hot a glow-plug and the needle needs to be set excessively open, the mid-range and transition become flawed.
...So these 'defective' Super Tigre .90 carburettors may happen, just because the glow-plug is the A3 that was supplied with the engine... Not only too much nitro that North Americans tend to use.
Think about it.