The micro plastic gearmotor’s output shaft works with with our 14 mm wheels. We don’t have any brackets for this gearmotor, and it generally does not have any installation holes, but its small size makes it easy to fasten with tape or glue. On the other hand, since this gearmotor is almost the same size as a 1/4″ fuse, it could be mounted using regular 1/4″ (6 mm) fuse clips.
Motor accessories
The following diagram shows the micro plastic gearmotor dimensions in mm. The planetary Micro Planetary Gear Motor gearbox includes a D-shaped plastic output shaft, which is 2 mm in diameter with a section that is flattened by 0.5 mm. The “D” part of the shaft is usually 2.5 mm long. The engine measures 6 mm in diameter and 9 mm long, and the gearbox length, labeled “L” in the diagram below, depends upon the apparatus ratio. The 26:1 gearbox is 
definitely 7.1 mm long, while the 136:1 option actions 9.4 mm. The engine leads come with their ideas pre-stripped and extend around 2 cm (0.8″) from the back of the motor.
Gearmotor dimensions
Because the gearmotor’s output shaft is nylon, there can be small variances in the diameter from unit to unit. These variations may cause press-fit attachments like our 14 mm wheel to match loosely in some instances. If you experience a loose fit, you could try swapping wheels or using a little dab of glue to help contain the wheel on.