In bike geometry, RC stands for Rear Center Length, which is the distance from the rear hub to the bottom bracket. It is more or less the chainstay length. However, in the context of bike registration, RC stands for Registration Certificate, which is an official document issued by the government of India that certifies a bike is legally registered with the Regional Transport Office (RTO) . Finally, in the context of riding clubs and motorcycle clubs, RC stands for Riding Club, which is a group of people who get together to ride motorcycles and enjoy the companionship of others with a similar interest. RC members are expected to participate as much as they are comfortable with and to answer questions as they are able. They are not normally out to hide anything and do not have colors, which are reserved for motorcycle clubs.