Stepper

Stepper (Side Swipe in English version) is a green Cybertron (Autobot). He's willing and eager, and also kinda dumb. He doesn't think before he leaps, gets really emotionally attached to commanders right away, and basically just messes things up. Convoy (Optimus Prime) thinks that somewhere in there is the makings of a fine future soldier.

Despite his childish nature, Stepper is apparently a capable codebreaker and does manage to make himself useful on a few occasions by deciphering Destron (Decepticon) data.

His Micron (Mini-Con in English version) partner is Chear (Nightbeat in English version), who actually encourages his behaviour.

(Source: Transformers Wiki, edited)