I have had more taken off the gear selector and the Layshaft taken down by 1.0mm. I have also swapped the second gear out for an old Italian 42 cog, 109.5mm diameter. I am still unsure whether the second gear I had in there was Indian, or not. All the gears spin freely on the layshaft.
The only other thing I noted was the gear cluster bearing track. I had replaced this when I built the engine but not knocked it in fully it seems. It stood 1.4mm proud of the casing. It is now 0.2mm proud. I suspect that this wasn’t the reason for struggling to get it into first gear but it may well have been the whirring noise I had.
All this is guesswork at the moment as I now need to put it all back together and try again.
Wish me luck.
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