Perhaps the most obvious technical change your bicycle goes through in its conversion to a Sport Utility Bicycle is the longer chain. Because the FreeRadical extends your wheelbase 15", a S.U.B. chain is 30" longer than it was before the conversion. Every FreeRadical kit includes 30" of chain (for 6,7 & 8 speed drivetrains). Which, in many cases, is all you need.
However, there are several reasons you might want to get something different: you might feel that your old chain is stretched, rusty and worn and in need of replacement anyway; you might have a 9 sp drivetrain; you might not like mixing chain brands (who claim incompatibility with other brands, although most of the time you won't notice a difference).
The 6,7,8 speed chain is KMC brand, of medium quality (silver-brown). The 9 speed chain is usually KMC brand as well, but sometimes Shimano or Sram. We only sell the 9-speed chain in S.U.B. lengths to maximize shifting performance and minimize potential breaks from splicing. Both full length chains sold here come with a "quick-link" to join the ends of the chain. You may need to shorten a full length chain based on your particular bicycle. If you don't feel confident to do this yourself, do have a trained professional assist you.
Over time, the desire for smaller jumps between gears has encouraged bike designers to increase the number of cogs on a rear wheel's cassette. In order to keep the wheel strong and hubs from being too wide engineers have decreased the spacing between cogs, which requires narrower chains to go with them. Thus, chains can be described by the number of gears or speeds on the rear wheel. Chains for 6, 7 or 8 gears are 7.1mm wide while nine speed chain is 6.6mm. Although not sold here, 10 speed chains are 6.1mm wide.