Trikes mostly fall into one of two main design categories: delta and tadpole. How do they compare?

Delta

One steered wheel at the front; two driven wheels at the back

Pro

• Simple steering
• Stable load platform at rear
• Weight concentrated at rear makes for good braking 
• Can be coupled in trains (Kettwiesel)
• “Easy-rider” image

Contra

• Complexity of two-wheel drive
• Centre of gravity tends to be high 
• Some models have poor cornering at speed
• long

Examples: Sinner, Hase Kettwiesel

Tadpole

One driven wheel at the back; two steered wheels towards the front (usually at about the position of the rider’s knees).

 Pro

• Simple drive (standard bike parts)
• Can carry standard bike/recumbent luggage
• Can be made (very) low
• Compact
• Easy to streamline (most velomobiles are tadpoles)
• Good high-speed cornering
• Widest part is where you can see it
• “Go-kart” image

 Contra

• Complicated steering
• Turning circle usually rather large 
• Getting on and off can be difficult (low height)
• Weight mostly on front wheels can lead to traction problems uphill, back end lifting under hard braking

Examples: Trice, Greenspeed, Windcheetah, Steintrikes, hp Scorpion, Alleweder, and many others