Shimano Alfine
Encyclopedia
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
Hub gear
A hub gear, internal-gear hub, or just gear hub is a gear ratio changing system commonly used on bicycles that is implemented with planetary or epicyclic gears. The gears and lubricants are sealed within the hub-shell of the bicycle's rear wheel, as opposed to derailleur gears, where the gears and...

, hydraulic disc brake
Disc brake
The disc brake or disk brake is a device for slowing or stopping the rotation of a wheel while it is in motion.A brake disc is usually made of cast iron, but may in some cases be made of composites such as reinforced carbon–carbon or ceramic matrix composites. This is connected to the wheel and/or...

s and levers, chain tensioners, dynamo hubs, cranksets
Crankset
The crankset or chainset , is the component of a bicycle drivetrain that converts the reciprocating motion of the rider's legs into rotational motion used to drive the chain, which in turn drives the rear wheel...

, shift levers
Shifter (bicycle part)
A bicycle shifter or gear control or gear levers is a component used to control the gearing mechanisms and select the desired gear ratio. Typically, they operate either a derailleur mechanism or an internal hub gear mechanism. In either case, the control is operated by moving a cable that connects...

, and complete wheels
Bicycle wheel
A bicycle wheel is a wheel, most commonly a wire wheel, designed for bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels....

. With the Alfine series Shimano
Shimano
Shimano, Inc. is a Japanese multinational manufacturer of cycling components, fishing tackle, and rowing equipment.In 2005, the company had net sales of US $1.4 billion. Bicycle components provided 75% of its sales income...

 introduced a series of innovations to the bicycling industry such as high-end multispeed epicyclic
Epicyclic gearing
Epicyclic gearing or planetary gearing is a gear system consisting of one or more outer gears, or planet gears, revolving about a central, or sun gear. Typically, the planet gears are mounted on a movable arm or carrier which itself may rotate relative to the sun gear...

 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).

Alfine 500

The Alfine 500 group, first introduced at Eurobike
Eurobike
Eurobike is an international exhibition around the bicycle and is held annually since 1991 in the first week of September, on the grounds of Messe Friedrichshafen, one of the largest and most modern exhibition centres in Baden-Wuerttemberg, Germany. The bike show is from Wednesday to Saturday for...

 in 2006, 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
Seal (mechanical)
A mechanical seal is a device which helps join systems or mechanisms together by preventing leakage , containing pressure, or excluding contamination...

 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 spline
Spline
Spline can refer to:* Spline , a mating feature for rotating elements* Spline , a mathematical function used for interpolation or smoothing* Smoothing spline, a method of smoothing using a spline function...

s for mounting a disc brake rotor of the center lock standard. The mechanisms are grease
Grease (lubricant)
The term grease is used to describe semisolid lubricants. Although the word grease is also used to describe rendered fat of animals, in the context of lubrication, grease typically applies to a material consisting of a soap emulsified with mineral or vegetable oil...

-lubricated.

Alfine 700

Alfine 700 is an internal epicyclic hub gear for bicycles, manufactured by Shimano
Shimano
Shimano, Inc. is a Japanese multinational manufacturer of cycling components, fishing tackle, and rowing equipment.In 2005, the company had net sales of US $1.4 billion. Bicycle components provided 75% of its sales income...

 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%. It is operated by a single ratcheting trigger shifter with two-way release. When introduced it had a claimed weight of approximately 1600g sans auxiliary components (bolts, actuator, cog, wire, shifter). Production models appeared to have a somewhat beefed up design. The internal mechanisms comprise four stepped planetary series in an oil bath
Oil bath
An oil bath is a laboratory heating device which uses boiling oil as the temperature regulator. Since different oils have different boiling points it is possible to obtain a temperature near to the desired temperature by selecting an oil with a boiling point as close as possible to the desired...

, for greater power transfer efficiency.
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