Hey @Bandit1052! Thank you for your input, useful as always! I hope that the diameter is large enough not to cause issues for the moment, knowing that the bike is pretty light and the power not that much.Yantosh is right: you can make axles out of stainless steel. But stainless steel is a very soft material. When it comes to performance, the right material for axles is 42CrMo4. This only serves as information for modifications.
Thanks! Indeed, there are soo many things you do not consider when starting a project like this. If you got shelves full of little parts and ready to bolt on bits, you skip lots of these operations. But I don't, so I need to buy or make them. Making them is faster than buying...sometimes.Very nice, lots of little details.