Hubbry Logo
CogsetCogsetMain
Open search
Cogset
Community hub
Cogset
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Cogset
Cogset
Cogset
View on Wikipedia
from Wikipedia
10-speed bicycle cassette

On a bicycle, the cassette or cluster[1] is the set of multiple sprockets that attaches to the hub on the rear wheel. A cogset works with a rear derailleur to provide multiple gear ratios to the rider. Cassettes come in two varieties, freewheels or cassettes, of which cassettes are a newer development. Although cassettes and freewheels perform the same function and look almost the same when installed, they have important mechanical differences and are not interchangeable.

Freewheels

[edit]
A freewheel and freewheel hub
A freehub (above) for use with a cassette and a threaded hub (below) for use with a freewheel

A freewheel (also known as a block) consists of either a single sprocket or a set of sprockets mounted on a body which contains an internal ratcheting mechanism and mounts on a threaded hub. Threaded rear hubs were available in different thread patterns depending on the country of manufacture, French and British threads being the most common. The British Cycle Engineers Institute (CEI) thread was adopted as the international standard[when?] and is now known as British Standard Cycle (BSC). It is a standardized right-hand 1-3/8″-24 TPI (M34.925×1.058 mm) thread onto which a standard freewheel is screwed.[2] This allows different brands of freewheels to be mounted on different brands of hubs.

The major disadvantage of the multiple sprocket freewheel design is that the drive-side bearing is located inboard of the freewheel, and as sprockets were added over time, the bearing moved inward, farther from the drive-side axle support. This resulted in more flexing stress being placed on the axle, which can bend or even break. Multiple speed freewheels were common on quality high end bikes until the late 1980s.[3] Suntour — Maeda Industries (Japan) introduced a compact 6 speed freewheel which reduced the spacing between the sprockets and was the same width as a standard 5 speed freewheel but required a narrower chain than the standard. The concept was copied by European freewheel manufacturers Regina (Italy) and Maillard (France).[4] As the number of sprockets on a multiple freewheel increased, and became physically wider, the freehub design overcame the axle/bearing problem associated with threaded hubs and began to supersede the freewheel design. Today[when?] it is rare to find a freewheel on a new bicycle with more than 7 speeds. Some new single-speed — especially BMX and utility bikes — and lower-end multi-geared bicycles continue to be manufactured and sold with freewheels.

Pedaling forces tighten a freewheel onto the hub, so no tool is required to install one. The ratcheting mechanism prevents the freewheel being loosened when the sprockets are turned counter-clockwise. A freewheel can be removed from the hub with one of the many specific freewheel removal tools that engages a spline or set of notches on the outboard end of the freewheel. Removal often requires considerable effort due to the large torque that tightens the freewheel during pedaling, and some freewheels cannot be removed intact. Future removal of a freewheel is facilitated by grease on the freewheel threads before installation.

Cassettes

[edit]
Shimano cassette and freehub

Cassettes are distinguished from freewheels in that a cassette has a series of straight splines that form the mechanical connection between the sprockets and the cassette compatible hub, called a freehub, which contains the ratcheting mechanism. The entire cassette is held on the hub by means of a threaded lockring. Some cassette systems from the late 1980s and early 1990s use a threaded small sprocket to hold on the larger splined sprockets. Cassettes resemble freewheels when installed, but are clearly different when removed as they do not contain a freewheel's internal ratcheting mechanism.

The sprockets in a cassette are usually held together by three small bolts or rivets for ease of installation. These keep the sprockets and spacers in the correct order and position when they are removed from the freehub body. When the sprockets need to be replaced due to wear or the user wishes to change gear ratios available, only the sprockets are replaced, not the ratchet mechanism. Cassettes also allow the use of sprockets with fewer teeth, as in micro drive systems.[5]

The ratchet mechanism, known as the freehub body, is still replaceable on most hubs, but forms a structural part of the hub. Cassette systems have a major advantage in that the drive-side axle bearing can be out near the frame, rather than being back towards the centre of the axle behind the freewheel. This greatly reduces the stress on the rear axle, making bent or broken axles extremely rare.

Since their introduction in the late 1970s[6] cassettes have been used on increasing numbers of bicycles, starting at the high-end and over time becoming available on less expensive bikes. Today[when?] the vast majority of bicycles with derailleur gears use this newer design.

Number and width of sprockets

[edit]

Over time, the number of sprockets in a cogset has increased, from 3 or 4 before World War II, to 5 used from the 1950s to the 1970s, up to the 8, 9, 10, 11, 12, and even 13 in the 2010s [when?] found on modern bikes. As more rear sprockets were added, the combination became wider, and the sprocket spacing narrower. One of the ways to make space for this was the axle length (measured as the over locknut distance — OLD.[7]) was increased, necessitating more dish on the rear wheel drive side with a threaded hub to centre the wheel in the frame. The hub flanges spacing was not shortened on threaded hubs, rather the axle length increased from 120 mm OLD (5-speed/compact-6) to 126 mm OLD (6-speed/compact-7) through to 130 mm OLD (threaded 7-speed) for a road bike. MTB rear spacing is normally 135 mm OLD. Another advantage of the Shimano cassette hubs introduced from 1978 was that the rear hub flanges were wider apart than those of a threaded hub, so built a stronger wheel with less dish and without the problem of increased bearing stress or axle failure.

Before the introduction of indexed shifting, the width of a 5-speed or compact-6 freewheel was approximately 32 mm; the introduction of indexed shifting supposedly made standardized sprocket spacing necessary. Shimano and Campagnolo both came up with independent standards, and SRAM later followed Shimano's lead in respect to sprocket spacing and cassette width. The width of early Shimano 6- and 7-speed cassettes was 36 mm, and early 8-speed 40 mm wide. Shimano then changed again and standardised 8-11 speed cassettes on 41.5 mm and second generation 7-speed to 38 mm. The widening of the sprocket carrier on the cassette hubs to 41.5 mm resulted in a decrease in the distance between the hub flanges.

For Shimano and SRAM the cassette spacing developed as follows. Early Shimano 7-speed cassettes are 36 mm wide, with sprocket spacing of 3.65 mm, but levers and rear derailleurs are not compatible with later Shimano 7-speed cassettes, which are 38 mm wide and have 3.2 mm sprocket spacing. An 8-speed cassette is wider at 41.5 mm than a second generation Shimano 7. This results in functionally compatible shifters, but specific freehub bodies, or necessitating the use of a spacer with a 7-speed cassette on an 8-speed hub. 8- and 9-speed cassettes and freehub bodies have the same width (41.5 mm), yet the sprockets on the 9-speed are closer together; as a result the shifters are not compatible, but they use the same freehub bodies. This development continued with 10-speed cassettes, but branched out for 11-speed cassettes. With them, new freehub bodies emerged which were either wider (Shimano road 11-speed) or entirely different (SRAM XD, XDr, which differ in width and both provide the space for a 10-tooth cog). For 12-speed, Shimano introduced a new freehub body as well (Microspline).

This progression has provided more fine adjustment of gear ratio, however the use of thinner metal parts has had the effect of shortening the life-span of the chain and sprockets due to so called "stretching" of the chain. This is caused by frictional abrasion of the load-bearing surfaces of the chain causing elongation. As such, the chain and sprockets of a 9-speed system require more frequent replacement than an 8-speed system.[citation needed] The narrowing of the hub flanges has created more dish in the wheel, which weakens the wheel if all other factors are the same, but improvements in the strength and reliability of spokes and rims has more than balanced this out, and wheel strength is generally higher despite the increased dish.

See also

[edit]

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Cogset

View on Grokipedia
from Grokipedia
A cogset, also known as a cassette, is a cluster of sprockets attached to the rear hub of a , providing multiple gear ratios that allow riders to adjust pedaling effort for different speeds and terrains. These sprockets, typically ranging from 7 to 13 in number, vary in tooth count from smallest (for high-speed pedaling) to largest (for easier climbing), enabling efficient power transfer from the chain to the . The cogset functions in conjunction with a rear , which shifts the chain across the sprockets to select the desired gear ratio, optimizing and reducing fatigue during rides. This system is standard on modern derailleur-equipped bicycles, including , , and models, where gear ranges are denoted by the smallest and largest sprocket sizes, such as 11-28 teeth for bikes or 10-52 teeth for bikes. Compatibility with the bicycle's body is essential, as most contemporary cogsets use splines to lock onto /SRAM Hyperglide (HG) or similar standards. Cogsets come in two primary varieties: freewheels and cassettes, distinguished by their mounting mechanism and design. Freewheels, introduced in 1898, are threaded units that screw directly onto the hub, incorporating both sprockets and a ratcheting freewheel mechanism for coasting. In contrast, cassettes separate the sprockets from the freewheel mechanism, which is integrated into the hub's body; this design allows for lighter weight, easier replacement of individual sprockets, and sturdier construction. Cassettes began replacing freewheels in the late 1970s and early 1980s, with pioneering widespread adoption around 1982 for improved durability and performance. Historically, the cogset evolved from early single-speed designs in the to multi-speed systems driven by advancements in technology and materials. The freewheel's invention in 1898 marked a pivotal shift, allowing riders to coast without pedaling, while multi-cog freewheels expanded to 5-6 speeds by the mid-20th century. The transition to cassettes in the 1980s facilitated higher gear counts—up to 13 speeds today—along with innovations like asymmetrical tooth profiles for smoother shifting. Modern cogsets are constructed from durable materials such as chromoly steel for affordability and strength, aluminum for reduced weight in mid-range models, and or carbon composites for high-end racing applications to minimize rotational mass. Leading manufacturers include , which dominates with its Hyperglide technology for precise shifts; SRAM, known for wide-range cassettes like the Eagle series; and , specializing in premium road components. These advancements continue to enhance efficiency, with recent models supporting up to 52-tooth largest cogs for steep climbs.

Overview

Definition and Purpose

A cogset is the complete set of sprockets, also known as cogs, mounted on the rear hub of a equipped with gears. This cluster enables the rider to achieve multiple gear ratios through the interaction of the chain with the sprockets and the rear , which shifts the chain between them. The primary purpose of a cogset is to provide variable , allowing efficient pedaling across diverse terrains by adjusting the gear ratio to suit the rider's effort and speed requirements. For instance, larger sprockets facilitate easier pedaling on climbs by reducing the force needed per revolution, while smaller sprockets enable higher speeds on flat or descending sections. This contrasts with fixed-gear systems, which lack multiple sprockets and offer only a single, unchangeable ratio, limiting adaptability to varying conditions. At its core, a cogset consists of individual sprockets with varying tooth counts, typically ranging from the smallest (for high ) to the largest (for low ), forming a unified cluster that engages during shifts. For example, a common configuration might feature sprockets from 11 to 32 teeth, providing a balanced progression of ratios for general riding. This arrangement ensures smooth transitions and optimal power transfer from the rider to the wheel.

Historical Evolution

The concept of the cogset originated with the invention of the mechanism, which allowed cyclists to coast without pedaling. In 1869, William Van Anden of , received U.S. No. 88,238 for an "improvement in velocipedes" that incorporated a freewheeling device in the front wheel of a , marking the first patented freewheel. This innovation laid the groundwork for rear-wheel applications, though it saw limited immediate adoption. Commercialization arrived nearly three decades later in 1898, when German industrialist Ernst Sachs produced the first widely available freewheel hub, enabling safer and more practical by decoupling the pedals from the rear wheel during descent or rest. Multi-speed cogsets emerged in the pre-World War II era, transitioning bicycles from single-gear limitations to more versatile configurations. By the 1930s, 3- to 4-sprocket freewheels became available, often paired with early systems that facilitated gear shifting. These designs built on the pioneering work of French cycling advocate Paul de Vivie, who developed derailleur-compatible mechanisms in the early and promoted multi-speed touring bicycles through his publication Le Cycliste, influencing European standards for geared rear clusters before his death in 1930. Mid-20th-century advancements refined cogset performance, particularly through Japanese manufacturer 's innovations in the 1960s and 1970s. introduced closer sprocket spacing in their Perfect and Pro Compe 6-speed freewheels, which expanded gear ranges—such as 14-34T—while maintaining compatibility with standard hubs, thereby improving shifting precision and overall efficiency for touring and racing applications. The late 1970s marked a pivotal shift from threaded freewheels to cassette systems, revolutionizing cogset design. In , launched the Dura-Ace EX series, featuring the first freehub body that mounted sprockets directly onto splines on the hub, which reduced lateral stress on the rear compared to traditional freewheels screwed onto the hub shell. This cassette system gained widespread adoption throughout the , becoming standard on high-end derailleur-equipped bicycles by the decade's end, as freewheels remained dominant only on lower-end or single-speed models until the late .

Types

Freewheels

A freewheel cogset is an integrated unit consisting of multiple sprockets, an internal mechanism, and a threaded body that screws directly onto the external threads of a compatible rear hub. The structure includes an inner body that engages the hub threads and an outer body housing the sprockets, with bearings separating the two to allow . These bearings are positioned inboard of the dropout face, within the hub shell. The mechanics of a enable one-way from to the , permitting coasting without pedal rotation. The system typically employs two pawls that engage a toothed ratchet ring, producing a characteristic ticking sound during freewheeling; when pedaling forward, the pawls lock against the ratchet to drive the . Under , the inboard bearing placement transfers stress to the , potentially leading to bending or breakage, particularly with higher gear counts or intense loads. Freewheels adhere to the ISO threading specification of 1.375 inches in diameter with 24 threads per inch (TPI); the British Standard Cycle (BSC) uses 1.370 inches x 24 TPI, with high compatibility between the two. Freewheels find primary applications on single-speed bicycles, , and low-end multi-speed setups limited to up to eight gears, though typically up to seven for practical use, where simplicity and cost-effectiveness outweigh performance demands. They are less common in modern high-gear configurations due to limitations in weight and durability. Compared to cassettes, freewheels offer simpler hub designs without requiring a dedicated body, but they are heavier due to the integrated ratchet and less efficient under high because of the cantilevered load on the . For instance, 1970s six-speed freewheels exemplified this design, featuring beveled teeth for smoother shifting but suffering from fatigue in demanding use.

Cassettes

Cassette cogsets represent the modern standard for multi-speed drivetrains, consisting of separate sprockets that stack onto a splined body and are secured by a threaded lockring, with the mechanism integrated into the rather than the cogset itself. This allows for modular assembly where individual sprockets slide onto the freehub's splines, enabling precise alignment and easy disassembly without disturbing the hub's internal components. Mechanically, the sprockets engage the splines for transfer, while the lockring—typically featuring 1.2-inch threads with 24 threads per inch—clamps the stack against the freehub's shoulder to prevent slippage under load. This configuration reduces stress on the by positioning the hub bearings outboard, closer to the wheel's flanges, which enhances overall wheel rigidity compared to threaded systems. The separation of the cassette from the ratcheting pawls also minimizes wear on the sprockets during coasting. Cassettes have become the dominant choice for derailleur-equipped , , and bicycles supporting 5 or more speeds, largely supplanting freewheels by the due to their integration with high-performance hubs. A pivotal development was Shimano's introduction of the cassette system around 1978–1980, initially for 6- and 7-speed setups, which set the foundation for widespread adoption in multi-gear applications. Key advantages of cassettes include lighter wheel construction, as the allows for a more compact hub design without an integrated body, and simpler sprocket replacement, where only the cassette stack needs servicing rather than the entire rear hub. However, this requires a compatible splined , limiting interchangeability with older threaded hubs. Overall, the cassette's prevalence stems from its role in enabling wider gear ranges and smoother shifting in contemporary disciplines.

Design Features

Sprocket Configuration

The number of sprockets in a cogset has evolved significantly to provide finer gear ratios and smoother progression between gears. In the early , cogsets typically featured 3 to 4 sprockets, enabling basic multi-gear setups on touring and bicycles. By the , this increased to 5 or 6 sprockets, as seen in standard freewheels that fit within traditional hub spacings. The and brought 7 to 10 sprockets, driven by advancements in indexing systems and materials, while contemporary cogsets commonly include 12 to 13 sprockets, allowing riders to maintain consistent across a wider range of terrains without large jumps in gearing. This progression toward more sprockets facilitates closer gear ratios, reducing the physical effort needed for speed changes. Tooth counts in cogsets are denoted by the range from the smallest to the largest sprocket, which directly influences the overall gear range available to the rider. For road bicycles, common configurations span 11 to 28 teeth or 11 to 32 teeth, providing a balanced setup for efficient pedaling on paved surfaces. Mountain bike cogsets, by contrast, often extend to wider ranges such as 10 to 52 teeth, accommodating steep climbs and technical descents with lower gears for torque. These ranges determine the mechanical advantage without delving into specific ratio calculations, prioritizing versatility for different cycling disciplines. The physical dimensions of a cogset, particularly its overall width, have adapted alongside the increase in sprocket count to maintain compatibility with frames. Early 5- to 6-speed cogsets measured approximately 24 to 30 in total width, fitting within rear hub dropout spacings of 120 . As sprocket numbers rose to 8 through 11 speeds in the late 20th and early 21st centuries, widths expanded to about 35 to 41 , necessitating adjustments in dropout spacing to 130 for road bikes and 135 for mountain bikes. These changes ensure proper alignment and function while accommodating the tighter sprocket spacing required for additional gears. Cogset configuration impacts both shifting performance and component longevity. Closer sprocket spacing, enabled by more cogs, enhances shifting precision by minimizing the distance the derailleur must travel between gears, resulting in quicker and more reliable changes under load. However, this tighter arrangement increases chain wear, as the chain operates under higher tension and with less tolerance for elongation, accelerating abrasion on both chain and sprockets if is neglected. A notable example is Suntour's Ultra-6 compact from the late , which achieved 6-speed functionality within a narrower 27 mm width—compared to the standard 30 mm—by reducing inter-sprocket gaps, allowing compatibility with 120 mm dropout spacings while improving shift quality on period bicycles.

Materials and Construction

Cogsets are primarily constructed from steel sprockets, which are either stamped for cost-effective production or CNC-machined for precision in higher-end models, providing durability and affordability suitable for everyday riding. Aluminum is commonly used for the largest cogs in cassettes, such as in certain SRAM XG-series variants, to reduce overall weight while maintaining structural integrity under lower-load conditions. Premium cogsets incorporate advanced materials like for select sprockets, as seen in Shimano's Dura-Ace R9200 12-speed cassette, where five or six cogs contribute to a total weight of approximately 223 grams for the 11-30T range. For corrosion resistance, many sprockets receive nickel-plating, which enhances longevity in wet or salty environments without significantly adding weight, as utilized in Shimano's Claris HG50 series. In freewheels, individual sprockets are typically riveted or pinned together into a single unit, with common designs featuring the three largest sprockets permanently joined by rivets for stability during threading onto the hub. Cassettes, by contrast, consist of a loose stack of independent sprockets that slide onto the freehub body and are secured by a lockring, though some models group mid-sized cogs with rivets or pins for easier handling and alignment, as in SRAM's XG-1275 where stainless steel pins connect steel cogs. Tooth profiles are engineered for optimal chain engagement, exemplified by Shimano's Hyperglide ramps that guide the chain smoothly during shifts by increasing contact surface area. These material choices directly influence performance: steel construction excels in longevity under the high-torque demands of , resisting wear from mud and impacts far better than alternatives. Lighter options like aluminum or prioritize applications, offering reduced rotational mass for quicker acceleration but accelerating wear rates when subjected to frequent high-load shifts. Nickel-plating extends service life in corrosive conditions, maintaining shifting precision over extended periods compared to uncoated .

Standards and Compatibility

Freehub and Thread Standards

Cogsets are mounted on rear hubs via standardized mechanical interfaces that ensure compatibility between the hub's body and the cogset assembly. For freewheels, the primary interface is a threaded connection directly to the hub, using the ISO standard thread of 1.375 inches in diameter with 24 threads per inch (TPI); the similar British Standard Cycle (BSC) uses 1.370 inches. This standard, established in the mid-20th century, allows freewheels to screw onto threaded hubs without a separate mechanism, providing a simple and durable mounting system for lower-speed setups. In contrast, modern cassettes utilize a splined body on the hub, where the cassette slides onto matching splines and is secured by an external lockring threaded into the hub. The /SRAM Hyperglide (HG) standard, dominant for 8- to 11-speed cassettes, features a splined interface with 9 primary splines, including a wider keyed slot for alignment to prevent incorrect installation. The lockring for HG cassettes engages via external threads on the body, typically with a of approximately 30.5 mm and a pitch of 1.06 mm (equivalent to 24 TPI), with an engagement length of about 5 mm to ensure secure retention under pedaling loads. For 12-speed systems, SRAM's XD and XDR standards introduce finer, stepped spline profiles to accommodate smaller starting cogs (as low as 10 teeth), differing from HG by extending the interface with precise notches rather than uniform splines; XD is used for applications, while XDR adds 1.85 mm length for and hubs to maintain spacing. Shimano's Spline for 12-speed employs 23 finer splines for improved distribution and compatibility with 10-tooth cogs, while maintains a standard with deeper, irregular splines (8 notches) exclusive to its cassettes, ensuring brand-specific fitment across 9- to 12-speed ranges. Hub compatibility is further governed by the over-locknut dimension (OLD), the total width of the rear hub, which has evolved from 120 for early road 5-speed setups to 130 for modern road cassettes and 135 for traditional mountain bike hubs, extending to 142 (thru-axle) or 148 (Boost) for contemporary MTB designs to accommodate disc brakes and wider tire clearances. Freewheels and cassettes are not interchangeable, as freewheels integrate the mechanism and thread directly onto the hub, whereas cassettes require a dedicated body with splines; mismatched systems can lead to installation failure or unsafe operation, and cogsets must align with width and capacity for proper shifting.

Modern Developments and Gear Ranges

The 11-speed era in cogset began in 2013 with Shimano's introduction of the Dura-Ace 9000 , which featured cassettes such as the 11-28t range for enhanced gear progression on road bikes. This advancement reduced spacing to approximately 3.74 mm center-to-center, allowing for more gears within a compact body while maintaining compatibility with existing Hyperglide systems. Advancements in 12-speed cogsets accelerated in the mid-2010s, with SRAM launching the Eagle drivetrain in 2016 for mountain bikes, offering a 10-50t cassette that provided a 500% gear range for tackling steep terrain. Shimano followed with its XTR M9100 series in 2019, introducing a 10-51t cassette compatible with the new Micro Spline , along with electronic shifting via Di2 integration for precise control. These developments emphasized durability and smooth shifting under load, with SRAM's AXS systems enabling cable-free setups across both brands. In 2025, released the Super Record 13-speed groupset, featuring a 13-sprocket cassette compatible with its proprietary standard, expanding options for and applications. Looking toward further advancements, filed a in 2025 for a electronic featuring a unique design to accommodate 13 sprockets and target even wider gear ranges beyond current 12-speed limits. Complementing this, SunRace released its CS160 12-speed ultralight series in 2025, optimized for applications with reduced weight and broad compatibility. Modern cogsets have expanded gear ranges significantly, with options reaching up to 520% via 10-52t cassettes for versatile climbing and descending, while cassettes commonly span 11-34t for balanced performance across varied routes. These ranges enable smoother gear progression and smaller percentage jumps between cogs, reducing disruptions during shifts. Key trends include lighter constructions, with many 12-speed cassettes weighing around 300 grams through optimized and combinations, enhancing overall . Increased e-bike compatibility has driven designs that withstand higher from assisted , supporting seamless integration with electronic . The global cassette market is projected to grow at a 4.5% CAGR from 2025 to 2034, fueled by rising demand for performance-oriented and sustainable components.

Installation and Maintenance

Fitting Procedures

Fitting procedures for cogsets differ based on the type, with freewheels threading directly onto the hub and cassettes sliding onto a body secured by a lockring. Ensuring hub compatibility is essential before installation to avoid damage or incompatibility issues.

Freewheel Fitting

The installation of a threaded begins with preparing the hub by applying a generous amount of grease or anti-seize compound to the threads, which aids in future removal and prevents . Place the rear wheel flat on a stable surface with the hub facing up, align the so that its cogs are parallel to the rim, and carefully thread it onto the hub clockwise by hand, checking for smooth engagement through the central hole to ensure the is centered. If resistance occurs early, remove and realign to prevent cross-threading, which can damage the soft aluminum hub threads. Once hand-threaded until snug, fully seat the freewheel by one of two methods: using a to rotate the cogs clockwise while bracing the wheel, or mounting the wheel in the , engaging the rear , and pedaling backwards to apply pedaling force.

Cassette Fitting

Cassette installation requires a compatible body, typically adhering to standards like HG or , which should be verified prior to proceeding. Remove any existing cassette if present, then align the splines of the smallest cog with the 's wide groove or key spline, and slide the entire cassette stack onto the body, ensuring spacers remain in their original positions for proper alignment. Apply grease to the lockring threads for smooth engagement and corrosion resistance, then thread the lockring onto the by hand until finger-tight. To secure the cassette, insert a cassette lockring tool (e.g., Park Tool FR-5.2 for /SRAM) into the lockring notches, reinstall the quick-release or axle nut to stabilize the wheel if needed, and tighten the lockring clockwise to 40 Nm using a to counter rotation and an adjustable wrench or .

Tools Required

Essential tools for cogset fitting include a freewheel remover (such as Park Tool FR-1 for threaded s), a (e.g., Park Tool SR-12.2) to prevent rotation during tightening, a cassette lockring tool (e.g., Park Tool FR-5.2), and a for precise application of specified torques. Always confirm tool compatibility with the specific or cassette brand to avoid spline damage. Safety notes emphasize checking hub compatibility—freewheels require threaded hubs (e.g., ISO or French standards), while cassettes need a splined —to prevent installation failures or unsafe riding conditions.

Common Errors

A frequent mistake during freewheel installation is cross-threading, often due to misalignment, which strips the fine hub threads and complicates removal. For cassettes, insufficient lockring torque below 40 Nm can lead to slippage under load, causing chain misalignment or component damage. To mitigate these, always start threading by hand and use a for final tightening.

Servicing and Replacement

Routine maintenance of cogsets involves periodic to remove dirt and debris, which can accelerate if left unaddressed. Cyclists should clean the cassette or with a neutral or degreaser periodically, depending on riding conditions (e.g., more frequently in wet or muddy environments), using a to scrub the sprockets while the chain is off or shifted away. After cleaning, dry thoroughly and apply sparingly to the chain, avoiding excess on the cogset itself to prevent attracting more grime. Inspection during these sessions should check for signs of , such as hooked or pointed teeth on the sprockets. Wear on cogsets is primarily caused by an elongated , which rides higher on the teeth and erodes the leading edges, resulting in a "shark-finning" appearance where teeth become asymmetrical and pointed. To detect this early, use a chain wear indicator tool; if the exceeds 0.5% elongation (or 0.75% for 9-speed or fewer systems), inspect the cogset closely, as continued use will damage it further. Visual cues include teeth worn to less than half their original depth on the largest sprocket, or skipping under load when paired with a new ; replacement is recommended at this stage to avoid poor shifting and premature failure of other components. Replacement of cogsets typically occurs after 2-3 chain replacements, though this varies with conditions like wet weather or heavy use, which can halve the lifespan. For freewheels, which are threaded units, removal requires a compatible freewheel remover tool (e.g., Park Tool FR-1.3 for Suntour) inserted into the splines, secured with the wheel's skewer, and turned counterclockwise with a large adjustable wrench while holding the wheel steady. The entire freewheel is then unscrewed and replaced as a unit, with threads lubricated before reinstalling the new one clockwise by hand and tightening fully. Cassettes, mounted on freehubs, are removed by first unlocking the lockring with a tool like the Park Tool FR-5.2 (12-spline for /SRAM), turned counterclockwise using a to prevent rotation. Once the lockring is off, slide the cassette stack from the splines; most modern cassettes are riveted in groups, requiring full replacement, though some older or aftermarket models allow individual swaps if not pinned together. Reinstallation involves aligning the splines, reinstalling any spacers, greasing the lockring threads, and hand-tightening clockwise to 40 Nm. When replacing a cogset, select one compatible with the existing and capacity to ensure smooth shifting. For e-bikes, which experience higher , opt for heavier-duty cogsets designed for electric drivetrains, as standard ones may wear out 2-3 times faster under motor-assisted loads. After any replacement, adjust the rear and test shifting across all gears.

References

  1. https://www.yellowjersey.co.uk/the-draft/bike-gears-explained/
  2. https://www.bikeradar.com/advice/workshop/bike-cassettes
  3. https://www.macvol.com/eu/blog/post/bicycle-cassettes-1
  4. https://rehook.bike/blogs/saddle-slang-the-dictionary-of-cycling-lingo/cogsets
  5. https://www.sheldonbrown.com/free-k7.html
  6. https://onlinebicyclemuseum.co.uk/tour/early-bicycle-hubs-gears-brakes/
  7. https://beck-bros-bmx.com/freewheels-vs-freehubs-cassettes
  8. https://www.bikeforums.net/classic-vintage/1155000-evolution-cassette.html
  9. https://www.canadabicycleparts.com/components/drivetrain/cassettes-cogs
  10. https://www.sheldonbrown.com/freewheels.html
  11. https://www.sixthreezero.com/blogs/bike-advice/single-speed-bike-or-multi-speed
  12. https://support.serial1.com/hc/en-us/articles/4418094310804-Single-Speed-Fixed-Geared-and-Multi-Speed-Bikes
  13. https://www.academia.edu/109270086/Design_and_Fabrication_of_Multi_speed_Bicycle_Sprocket_on_CNC_Milling_Machine
  14. https://americanhistory.si.edu/collections/object/nmah_843309
  15. https://evelo.com/pages/history-of-the-bicycle
  16. https://www.disraeligears.co.uk/site/de_vivie_derailleurs.html
  17. https://www.sheldonbrown.com/suntour.html
  18. http://www.shimano.com/en/100th/history/products/14.php
  19. https://www.bmx-forum.com/threads/freewheels-and-cassettes-explained.150699/
  20. https://www.danscomp.com/cogs-freewheels-race-parts/c16046
  21. https://eskute.co.uk/blogs/news/freewheel-versus-cassette
  22. https://www.sheldonbrown.com/k7.html
  23. https://www.parktool.com/en-us/blog/repair-help/cassette-removal-and-installation
  24. https://www.disraeligears.co.uk/site/shimano_bicycle_system_components_may_1978.html
  25. https://www.parktool.com/en-us/blog/repair-help/determining-cassette-freewheel-type
  26. https://www.sheldonbrown.com/cribsheet-spacing.html
  27. https://cyclejourneys.co.nz/all-about-gears/
  28. https://www.trainerroad.com/blog/a-guide-to-bicycle-gearing-choosing-the-right-gears-for-your-road-gravel-and-mountain-bike/
  29. https://velo.outsideonline.com/road/road-racing/technical-faq-shifting-problems-and-cog-spacing/
  30. https://www.bikeradar.com/advice/workshop/how-to-know-when-its-time-to-replace-your-bicycle-chain
  31. https://bicycles.stackexchange.com/questions/76864/is-my-cassette-made-of-steel
  32. https://bike.shimano.com/products/components/pdp.P-CS-R9200-12.html
  33. https://www.bicycle-house.com/shimano-claris-cs-hg50-cassette-8-speed-12-25t-sil.html
  34. https://forum.cyclinguk.org/viewtopic.php?t=139420
  35. https://www.competitivecyclist.com/sram-xg-1275-gx-eagle-12-speed-cassette
  36. https://bike.shimano.com/stories/article/hyperglide.html
  37. https://www.lightbicycle.com/newsletter/Bike-Freehub-Cassette-Compatibility-Manual.html
  38. https://www.bikeforums.net/bicycle-mechanics/508181-shimano-cassette-lock-ring-thread-size.html
  39. https://www.sram.com/en/service/articles/sram-xd-and-xdr-driver-body-explained
  40. https://enve.com/blogs/journal/freehubs-explained-what-are-xdr-and-micro-spline
  41. https://www.bikeradar.com/advice/buyers-guides/freehubs
  42. https://www.sheldonbrown.com/frame-spacing.html
  43. https://bike.bikegremlin.com/158/bicycle-rear-hub/
  44. https://bicycles.stackexchange.com/questions/64799/are-freewheels-and-cassettes-interchangeable
  45. https://road.cc/content/news/58457-first-ride-shimano-dura-ace-11-speed
  46. https://www.celebrazio.net/bicycling/shimano/2009_compatibility.html
  47. https://www.bikeforums.net/road-cycling/937839-let-s-talk-crankset-chainring-spacing-between-10s-11s.html
  48. https://www.bicycleretailer.com/product-tech/2016/03/23/sram-launches-1-12-eagle-mountain-drivetrain-50-tooth-large-cog
  49. https://nsmb.com/articles/2019-shimano-xtr-9100-10-51-12spd-here/
  50. https://www.pinkbike.com/news/review-shimano-xtr-m9100-12-speed-drivetrain.html
  51. https://bikerumor.com/campagnolo-super-record-13-wireless-2x13-speed-road-groupset-is-lighter-faster-more-affordable-and-coming-to-gravel-soon/
  52. https://off.road.cc/content/news/shimano-launches-a-two-pronged-attack-on-srams-full-mount-system-with-unique-13-speed
  53. https://www.wiseguyreports.com/reports/bicycle-cassette-market
  54. https://bikepacking.com/gear/eagle-gx-10-52t-review/
  55. https://us.huntbikewheels.com/products/shimano-ultegra-12-speed-cassette-cs-r8101-11-34t
  56. https://www.reddit.com/r/bikewrench/comments/zkkq1t/105_vs_ultegra_12speed_cassettes_how_is_ultegra/
  57. https://www.archivemarketresearch.com/reports/bike-cassette-118166
  58. https://www.gminsights.com/industry-analysis/bicycle-drivetrain-cassette-market
  59. https://www.parktool.com/en-us/blog/repair-help/freewheel-removal-and-installation
  60. https://www.parktool.com/en-us/blog/repair-help/torque-specifications-and-concepts
  61. https://si.shimano.com/en/pdfs/dm/TORQUE/DM-TORQUE-00-ENG.pdf
  62. https://si.shimano.com/en/pdfs/dm/RACS010/DM-RACS010-02-ENG.pdf
  63. https://rouvy.com/blog/how-to-clean-bike-chain
  64. https://escapecollective.com/threaded-24-a-modern-guide-to-measuring-chain-wear/
  65. https://www.parktool.com/en-us/blog/repair-help/when-to-replace-a-chain-on-a-bicycle
  66. https://www.cyclingweekly.com/products/how-often-should-you-replace-your-chain-and-cassette-and-does-cross-chaining-really-matter
  67. https://www.pedelecs.co.uk/forum/threads/having-to-replace-cassette-after-only-500-miles-cube-touring-pro-625.46730/
  68. https://www.cyclechat.net/threads/giant-e-bike-chain-and-cassette-need-replaced-too-often.265454/
Add your contribution
Related Hubs
User Avatar
No comments yet.