You will get about 2x the energy / cost density from Trojan t1275 batteries. They will last longer too. Yes, they are a wet lead-acid battery, but are the best bang for the buck. The 82 pounds gets you 12v at 150 amp hours (c/20 rate) !! Cost of about $200 each
Trojan
Optima BlueTop D31M (60 pounds) gives you about 75 ah for about $200.
Specs & Tech - Technical Specifications
Advanced DC motors are about the most reliable you can get. They spin very fast if need be.
EVAlbum: Advanced DC Motor
Here is a great place to look for EV stuff - my cousin did an EV conversion on a Saturn.
Saturn From SC2 to a EV 120 Volts DC - EV FORUM - ELECTRIC VEHICLE FORUM