Motorized Steampunk Tricycle

A motorized tricycle's wheels may be arranged in either configuration: delta or tadpole. A delta trike has one wheel in front and two in back, and the tadpole trike has two wheels in front and one in back. Occasionally, rear wheel steering is used, although this increases the turning circle and can affect handling (the geometry is similar to a regular trike operating in reverse, but with a steering damper added). Thrust SSC used a rear-steer tadpole layout.
Tadpoles are more stable under braking and more likely to slide instead of roll; front braking hard on a delta requires the vehicle to steer almost straight to avoid tipping. The balance of friction patches and rolling resistance also means that tadpoles tend to understeer and deltas oversteer.
Motor trikes are attractive for those with mobility or balance problems, for carrying multiple passengers on a motorcycle license (since January 2013 in Great Britain a full car license is required for ANY trike), or to avoid helmet use regulations. These machines are generally custom-built and often finished to a very high standard. A common arrangement is to fit chopper-style ("ape hanger") front forks to a VW Beetle engine and transaxle, popular because it is largely self-contained on a single subframe. Similarly, the engine, transmission and rear wheel may be taken from a large motorcycle as a single unit, and used in the construction of a tadpole trike.
Mass-manufactured motor tricycles include the Piaggio MP3; the Piaggio Ape (Italian for Bee) delivery trike (delta); the Harley-Davidson Tri Glide Ultra Classic; the Bombardier Recreational Products Can-Am Spyder (tadpole); the T-Rex reverse trike; trikes used by municipal authorities in the USA; and, historically, vehicles such as the Scammell Scarab railway dray, a common sight around post-war British railway stations.