Rohloff Speedhub - AbsoluteAstronomy.com

The Rohloff Speedhub is an 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...

internal hub gear

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...

for bicycle

Bicycle

A bicycle, also known as a bike, pushbike or cycle, is a human-powered, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A person who rides a bicycle is called a cyclist, or bicyclist....

s, developed and patent

Patent

A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....

ed by Rohloff AG

Rohloff AG

Rohloff AG is a German company from Fuldatal near Kassel that manufactures hub gears, bicycle chains and tools that are known for their durability and high performance...

. It has been manufactured and marketed by the German company since 1998. The Speedhub 500/14 has 14 equally-spaced sequential gears with no overlapping ratios and is operated by a single twistgrip. The overall gear range is 526 %, meaning the highest gear is 5.26 times as high as the lowest gear. Individual gear shifts give an increase or decrease of 13.6 %.

The Speedhub is more expensive than competing bicycle gear systems (both hub gears and derailleur gears), but it combines the robustness of hub gears with the gear number and gear range of derailleur gears. It is therefore mainly used in high-quality touring bicycle

Touring bicycle

A touring bicycle is a bicycle designed or modified to handle bicycle touring. To make the bikes sufficiently robust, comfortable and capable of carrying heavy loads, special features may include a long wheelbase , frame materials that favor flexibility over rigidity , heavy duty wheels , and...

s and in mountain bike

Mountain bike

A mountain bike or mountain bicycle is a bicycle created for off-road cycling. This activity includes traversing of rocks and washouts, and steep declines,...

s, where its robustness and the lack of (vulnerable) external components is useful.

Versions

There are several different versions of the hub for different applications that a bicycle might be used in:

TS (Touring Axle)
DB (Disc Brake)
CC (Cross Country)
EX (external Gearbox)
OEM (original equipment manufacturer)
OEM2 (like OEM, for frames with Disc Brake mount, after IS 2000)
T (Tandem)

The hubs are available in different colors: silver (aluminum polished), red or black.

Operation

The internal construction of the gear hub consists of three planetary gear series, connected one after the other, selectively engaged depending on the user’s gear choice, each comprising a stepped planet. The first two gear series provide seven ratios, and the third a complete range reduction, doubling the number of speeds to fourteen. The first two stepped series are identical and mirrored, each offering two ratios and direct drive. Each planet level meshes with a sun gear, and each smaller planet meshes with an annulus. Shifting is achieved by locking each sun in turn, using pawls, and locking the first and second series to direct drive with an axial clutch. The first planetary serie gears three and two steps up respectively, while the second gears two and three steps down respectively, both also having direct drive. One step up is achieved by combining three steps up with two steps down, and one step down by combining two steps up with three steps down. Thus three different steps up, direct drive and three different steps down is achieved by a double planet system, all in even increments due to the cog sizes selected. The reduction gear is a standard unit known from the art.

The IGR, hub revolutions per sprocket revolution of the Speedhub, lies between 0.279 and 1.467 depending on the gear chosen. The Speedhub has a 526 % range between the highest and lowest gear. Gear 11, with a ratio of 1.0, is called the neutral gear.

The overall average loss of the gears is about 1 %–5 %, comparable to a derailleur.

The range of gears in detail is:

Gear	1	2	3	4	5	6	7	8	9	10	11	12	13	14
IGR	0.279	0.316	0.360	0.409	0.464	0.528	0.600	0.682	0.774	0.881	1.000	1.135	1.292	1.467

Mounting

The Speedhub is provided with a twist shifter for shift operation, with one cable pulling in each direction. The indexing mechanism is part of the hub.

Like all hub-gears, there is a torque reaction that must be countered if the internals are not to rotate, and this is routed to the bicycle’s frame by means of specially designed wheel dropout slots (OEM versions), or a torque bar bolted to the frame (EX) or the disc brake mount (DB). Many riders prefer to have the hub fitted to a new and purpose-built bicycle.

The hub contains 25 ml of oil which should be replaced once a year or after 5,000 km (manufacturer advice). Overfilling can lead to leaks, as can laying the hub/cycle on its side in some low-pressure aircraft holds.

The cog on the hub is made for standard-pitch derailleur-type bicycle chains 1/2″ x 3/32″ (ISO 082) and is offered with different numbers of teeth, like 13/15/16/17. The 15-, 16-, and 17-tooth cogs are reversible, offering double cog life once the cog is worn out in one direction. The 13-tooth cog is non-reversible and has a slight outward offset, changing the chain-line slightly. This because the smaller cog makes the chain run closer to the axle, and the chain would rub the hub shell if the cog was not offset.

Technical data

Frame spacing:	135 mm
Spoke hole circle diameter:	100 mm
Number of spokes:	32
Axle diameter at dropout:	9.8 mm
Oil amount:	25 ml
Sprocket thread:	M34 x 6 P6
Chain line:	54 mm (58 mm with 13-tooth cog)
Twist shifter angle per gear:	21°
Shifter cable movement per gear:	7.4 mm
Price:	above EUR 800

Break-in period

Rohloff hubs generally require a break-in period to function optimally. The manufacturer suggests this may require 500-1000 miles of active riding. For some riders the break-in period may be longer. Until the hub is broken in the rider may experience some noise or vibrations when the reduction-gear is in operation (1-7 gear).

Robustness

The Rohloff Speedhub is well known for its robustness and reliability. Since its introduction, there have been few reported incidents of the internal mechanisms failing.

There have however, been a few reported incidients of the flange of the hub shell developing fractures or failing. These units have generally been replaced under warranty

Warranty

In business and legal transactions, a warranty is an assurance by one party to the other party that specific facts or conditions are true or will happen; the other party is permitted to rely on that assurance and seek some type of remedy if it is not true or followed.In real estate transactions, a...

External links

link broken! SPEEDHUB 500/14 Owner’s Manual (the main part of which is accessed by clicking the item subtitled "General info...")
Living with a Rohloff Hub by Andy Blance of Thorn Cycles
Thorn Cycles
Thorn Cycles is a British manufacturer of bicycles based in Bridgwater, Somerset. They specialise in tandems, touring and randonneuring cycles.They have recently become well known for their Raven series of cycles equipped with Rohloff hub gears...
Kinetic’s Rohloff page
How to change oil and How to change your sprocket by Eric Schuijt of De Vakantiefietser, Amsterdam.

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.