Well you can't slow them down, only speed them up as there were only ever two different gears made, larger one for petrol and smaller for the electrics, but yes you are correct that the electric motor had slower RPM's which when geared up worked out to an average walking speed behind a mower, remembering though that you can't vary the speed of the electric apart from slipping the land roll clutch which isn't the best method in the long term.
Cheers,
BB.
