Not strictly ebike related but if i bought an ebike with a double chainring, would it be possible to use just one ring and be able to use all of the 8 speed cassette. Can the double ring be moved, leaving one of the rings in line with centre of cassette. Or remove a ring and shim the other to the centre position. Would this allow me to use all the cassette on one ring, keeping the front derailleur but not using it.