The Mundo comes with a 48-spoke, tandem-strength rear wheel that has a 14mm axle. Most mountain bike wheels, internally geared hubs. To adapt these smaller axles to the Mundo’s frame, you can use an axle adaptor.
Veteran Mundo rider and mechanic Mike Cobb writes:
BMX kids often use 3/8″ (9.525mm) axles in 14mm dropouts by using very simple adaptors. I’m 99% sure that 10mm axles will be compatible with these adaptors:
Can anyone help us move from 99% sure to 100% sure?