Crown wheel and pinion is 1200 €, plus at least 800 € for the conversion. That's a lot of money. The question is, is worth the money?
In theory, you don't need a new crown wheel, just a new pinion gear with one fewer teeth
For straight-cut gearsets, yes. But I thought helical gearsets had the pinion matched to the crownwheel and always needed changing in pairs otherwise the pitch/profile mismatch would cause the gears to eat themselves?
Stuart "There's no skill substitute like cubic inches."