High Carbon Steel Road Bike 700C Wheels For Men And Women 21 Speed Disc Brakes Product introduction: The road bike has a 21-speed gearbox system. The correct use of the gearbox can deal with complex road conditions and weather such as flat roads, up and down slopes, dirt roads, and wind. The road bike adopts curved road handlebars, which can greatly reduce the resistance of the riding stroke and make your riding faster and more labor-saving. The road bike frame is suitable for height 5'7" ~5'9". The frame of this road bike is made of high carbon steel. The biggest advantage of high-carbon steel frame is sturdiness and durability. 700C road bike tires can effectively reduce unnecessary bumps caused by uneven road surface during riding, greatly reduce fatigue caused by riding vibration, and.