This is not technically a monotread, but the overall effect is the same, with all treads moving together. It is relatively fast, with 2 M PF motors at a 3:1 gear ratio, although there is no steering available since when I made this I didn't have any IR controllers. The first version of this creation can be seen here http://www.mocpages.com/moc.php/231914
About this creation
A look at the gears. One of the motors is directly attached to the top 16-tooth gear
Without the tread.
The "switch" to turn it on can be seen on the bottom left, attached to the battery box