In 1975 I worked on a CZ shop, A 250 enduro owner came in and ordered a 400 MZ. When we got the 400
he had the shop do the following mods. Swap the 400 4spd gearbox for the 250 5 spd (easy mod, a little grinding on the 400 left tranny case), we then installed a reed valve, mikuni, motoplat ignition, air fork and konis. What a machine, this bike could win local MX events and then go destroy the competition in open class enduros.
The 250 was re-assembled with the 400 4 spd gearbox, this bike also turned out to be a very good enduro
bike. The 250 even with the breaker point ignition and Jikov carb always started on the first or second kick, it was very pleasant bike to ride.
