Who was the first rider from mainland Europe to gain a podium position.
Place Bike and Year?

Pietro Ghersi, Guzzi, 1926 Lightweight, 2nd place, but only briefly.

Excluded from the results for using a make of plug different from that declared at weigh-in.

Oddly, he kept his fastest lap award though.

Had to wait until 1936 for the next - Arthur Geiss on a DKW in the Lightweight again - 3rd I think.

Very close Larry but not right according to the TT centenary programme where i got the question from.
There it lists 1927 Luigi Archangeli 2nd on a 250cc Moto Guzzi