Chainless bicycles were moderately popular in 18, although sales were still much smaller than regular bicycles, primarily due to the high cost. During this period, Columbia aggressively marketed the chainless bicycle in the USA. The French company L'Acatane did most of the development in the 1890s. The shaft-driven bicycle was originally developed in the late 1800s.

This is particularly noticeable when pedaling hard, when there can be noticeable torsional springing in the drive train. This mitigates against shaft drive as the shafts must be large to cope with the torque, which adds to their mass. Not all hub gear systems are shaft compatible.īicycles typically employ more torque (an adult man can easily generate more than 100 ft-lb) but at much lower rotational speed than motorcycles and cars. The reduced need for adjustment in shaft-drive bikes also applies to a similar extent to chain or belt-driven hub-geared bikes. Some of the other issues addressed by the shaft drive, such as protection for clothing and from ingress of dirt, can be met through the use of chain guards. Changing a flat: shaft drives are typically more complex to disassemble when repairing punctures.

Weight: A shaft-driven bicycle typically weighs about one pound (454 grams) more than an equivalent chain-driven bicycle.

Gear range: Internal hub geared bikes typically have a more restricted gear range than comparable derailleur-equipped bikes, and have fewer ratios within that range (an issue because a rider typically prefers to pedal within a fairly narrow cadence band).

Cost: Due to the manufacturing complexity of the frame and shaft drive, the manufacturing cost is typically higher.

Complexity: Though the shaft-driven system seems simple on the outside, the manufacture of the necessary bevel gears is complex compared to that of a chain and sprockets.

Shaft driven systems are often quoted as being '95% efficient', while chain driven systems are quoted as '98% efficient'.

Power loss: A shaft-driven system is less efficient than a chain-driven system.

Reduced maintenance and repair: Enclosed gears are less susceptible to damage and require less adjustment or cleaning.

Longevity: Enclosed gears keep their performance stable for a long time.

Cleanliness: Enclosed gears cannot get grease on hands or clothing.

Safety: There is no danger of clothing or fingers being drawn into the enclosed gears.

Enclosed drive system: Enclosing the drive shaft and gears provides several benefits:.

Gear shifting: Since shaft-drives require gear hubs for shifting at all, they gain the benefit that gears can be shifted while the bicycle is at a complete stop or moving in reverse.

Consistency of performance: Shaft drives operate at a very consistent rate of efficiency and performance, without adjustments or maintenance.

Ground clearance: The drive shaft system allows greater ground clearance.

Compactness: The drive shaft and bevel gears take up less volume than an enclosed chain.

Most of the advantages claimed for a shaft drive can be realized by using a fully-enclosed chaincase. chain drives can only be made if both bikes use the same type of gearing, whether single-speed or with an internal gear system. Right-hand shift lever File:Bevelgear.jpgīevel ring gear on the rear wheel of a shaft-drive bicycleĪ valid comparison of shaft vs. Today, there are three significant manufacturers of internal hubs suitable for use with shaft drive systems, including Shimano Nexus, SRAM and Sturmey-Archer. The driveshaft is often mated to a hub gear which is an internal gear system housed inside the rear hub. Bevel gears are the most efficient way of turning drives 90 degrees as compared to worm gears or crossed helical gears. The 90-degree change of the drive plane that occurs at the bottom bracket and again at the rear hub requires the use of bevel gears. The drive shaft then has another bevel gear near the rear wheel hub which meshes with a bevel gear on the hub where the rear sprocket would be on a conventional bike, and canceling out the first drive torque change of axis.

The use of bevel gears allows the axis of the drive torque from the pedals to be turned through 90 degrees. This meshes with another bevel gear mounted on the drive shaft. Shaft-driven bikes have a large bevel gear where a conventional bike would have its chain ring. Recently, due to advancements in internal gear technology, a small number of modern shaft-driven bicycles have been introduced. Shaft drives were introduced over a century ago, but were mostly supplanted by chain-driven bicycles due to the gear ranges possible with sprockets and derailleurs.

Dynamic 'Runabout' 7 shaft-driven bicycleĪ shaft-driven bicycle is a chainless bicycle that uses a drive shaft instead of a chain to transmit power from the pedals to the wheel.

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