Highlights

• By 1931 the evolution of the Ace Four into the Indian Four was nearly complete
• Indian had replaced the Ace frame with the Indian double downtube frame, upgraded the front brake, replaced the rear frame section with one patterned after the 101 Scout, increased the wheelbase by 1.5 inches, and redesigned the fuel tank, all adding 60 pounds
• Indian also increased the engine main bearings count from the Ace (3) to the Indian (5) and redesigned the pistons and cylinder heads for better performance
• The Indian Four is a forever classic, beautiful lines, amazing engine, wonderful sound and amazing ride