The Shimano Alfine series of products is a comfort and urban oriented product series first seen by the market around 2005. It includes internally geared hubs, hydraulic disc brakes and levers, chain tensioners, dynamo hubs, cranksets, shift levers, and complete wheels.[1] With the Alfine series Shimano introduced a series of innovations to the bicycling industry such as high-end multispeed epicyclic hubs for urban use, internally geared hubs with center lock disc mounts, and attractive designs. Two generations have been launched, the 500 (2006) and 700 (2010).
The Alfine 500 group, first introduced at Eurobike in 2006,[2] included the epicyclic hub gear SG-S500. The internal mechanical design of the gear hub was based on that of the Shimano Nexus Inter 8, with three stepped planetary series mounted downstream of each other, thus offering 8 speeds with percent intervals of 22,16,14,18,22,16,14, and an overall gear range of 307%, yet in a more attractive design than the Nexus, with better seals allowing slightly greater ruggedness, more attractive auxiliary components such as e.g. a ratcheting trigger shifter similar to the high-end Shimano derailleur shifters, and a hub shell with splines for mounting a disc brake rotor of the center lock standard. The mechanisms are grease-lubricated.
Alfine 700 is an internal epicyclic hub gear for bicycles, manufactured by Shimano since 2010. The 700 has 11 speeds, with intervals of approximately 29% for the first to second gear gap, and 13% - 14% for the other gears, resulting in an overall gear range of 409%.[3] It is operated by a single ratcheting trigger shifter with two-way release.[4] When introduced it had a claimed weight of approximately 1600g sans auxiliary components (bolts, actuator, cog, wire, shifter)[5]. Production models appeared to have a somewhat beefed up design.[6] The internal mechanisms comprise four stepped planetary series in an oil bath, for greater power transfer efficiency.