79-488: The Crocodile Trophy is an annual eight-day mountain bike stage race held in North Queensland , Australia . The race typically covers around 750 kilometres (466 mi) over 8 stages and used to be known as one of the most demanding mountain bike races in the world, called 'the hardest, longest and most adventurous MTB race in the world'. In recent years however the race became more and more accessible. The race
158-528: A freewheel mechanism to allow coasting. The gearing supplied by the manufacturer on a new bicycle is selected to be useful to the majority of people. Some cyclists choose to fine-tune the gearing to better suit their strength, level of fitness, and expected use. When buying from specialist cycle shops, it may be less expensive to get the gears altered before delivery rather than at some later date. Modern crankset chainrings can be swapped out, as can cogsets . While long steep hills and/or heavy loads may indicate
237-467: A suspension fork , large knobby tires , more durable wheels , more powerful brakes, straight, wide handlebars to improve balance and comfort over rough terrain, and wide-ratio gearing optimized for topography , application (e.g., steep climbing or fast descending) and a frame with a suspension mechanism for the rear wheel. Rear suspension is ubiquitous in heavier-duty bikes and now common even in lighter bikes. Dropper seat posts can be installed to allow
316-416: A (relatively small) whole number of teeth it is impossible to achieve a perfect progression; for example the seven derailleur sprockets 14-16-18-21-24-28-32 have an average step size of around 15% but with actual steps varying between 12.5% and 16.7%. The epicyclic gears used within hub gears have more scope for varying the number of teeth than do derailleur sprockets, so it may be possible to get much closer to
395-419: A 10-speed, 11-speed or 12-speed cassette, and the intricacies of a 10-speed, 11-speed or 12-speed rear derailleur were originally not found to be suitable combined with front shifters, although 10, 11 and 12 speed cassettes are now commonplace in single front chainring bicycles, and are also found on some mountain bikes. However, many pro-level mountain bikers have taken to using a narrower 10-speed road chain with
474-411: A 9-speed setup in an effort to reduce the weight of their bike. In early 2009, component group SRAM announced their release of their XX groupset, which uses a 2-speed front derailleur, and a 10-speed rear derailleur and cassette, similar to that of a road bike. Mud-shedding capabilities of their 10-speed XX cassette are made suitable for MTB use by extensive Computer Numerical Control (CNC) machining of
553-481: A Schwinn Varsity frame. Mert Lawwill had Terry Knight of Oakland build the frames. The bikes sold for about $ 500 new and were made from 1979 though 1980 (approximate run of 600 bikes). The first mass production mountain bike was the Specialized Stumpjumper , first produced in 1981. With the rising popularity of mountain bikes, Randolph (Randy) Ross, executive vice president of Ross Bicycles Inc. ,
632-454: A bicycle frame builder, used this idea and developed what is considered the first mountain bike. It was not until the late 1970s and early 1980s that road bicycle companies started to manufacture mountain bicycles using high-tech lightweight materials, such as M4 aluminum. The first production mountain bike available was the 1979 Lawwill Pro Cruiser. The frame design was based on a frame that Don Koski fabricated from electrical conduit and
711-435: A change from a 20-tooth sprocket to a 23-tooth sprocket (15%), even though the latter has a larger absolute difference. To achieve such consistent relative differences the absolute gear ratios should be in logarithmic progression; most off-the-shelf cogsets do this with small absolute differences between the smaller sprockets and increasingly larger absolute differences as the sprockets get larger. Because sprockets must have
790-427: A derailleur-equipped bicycle with 3 chainrings and an 8-sprocket cogset: The combination of 3 chainrings and an 8-sprocket cogset does not result in 24 usable gear ratios. Instead it provides 3 overlapping ranges of 7, 8, and 7 gear ratios. The outer ranges only have 7 ratios rather than 8 because the extreme combinations (largest chainring to largest rear sprocket, smallest chainring to smallest rear sprocket) result in
869-411: A few gear ratios which have a straight chain path, but most of the gear ratios will have the chain running at an angle. The use of two derailleurs generally results in some duplicate or near duplicate gear ratios, so that the number of distinct gear ratios is typically around two-thirds of the number of advertised gear ratios. The more common configurations have specific names which are usually related to
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#1732786883589948-439: A further factor is needed to allow for any other selected hub gear ratio (many online gear calculators have these factors built in for various popular hub gears). The following table provides some comparison of the various methods of measuring gears (the particular numbers are for bicycles with 170 mm cranks, 700C wheels, and 25 mm tyres). Speeds for several cadences in revolutions per minute are also given. On each row
1027-449: A gear at too low a cadence can increase the chance of knee damage; cadence above 100 rpm becomes less effective after short bursts, as during a sprint. There are at least four different methods for measuring gear ratios: gear inches , metres of development (roll-out), gain ratio , and quoting the number of teeth on the front and rear sprockets respectively. The first three methods result in each possible gear ratio being represented by
1106-469: A larger than average jump to the next lowest gear. In the 1960s the term was used by salespeople to refer to then current 10-speed bicycles (2 chainrings, 5-sprocket cogset), without any regard to its original meaning. The nearest current equivalent to the original meaning can be found in the Shimano Megarange cogsets, where most of the sprockets have roughly a 15% relative difference, except for
1185-400: A moderate relative difference of around 15%; this allows for a much larger gear range while having an acceptable step between gears. 3-speed hub gears may have a relative difference of some 33% to 37%; such big steps require a very substantial change in pedalling speed and often feel excessive. A step of 7% corresponds to a 1-tooth change from a 14-tooth sprocket to a 15-tooth sprocket, while
1264-423: A need for lower gearing, this can result in a very low speed. Balancing a bicycle becomes more difficult at lower speeds. For example, a bottom gear around 16 gear inches gives an effective speed of perhaps 3 miles/hour (5 km/hour) or less, at which point it might be quicker to walk (bike shoes permitting). As far as a cyclist's legs are concerned, when changing gears, the relative difference between two gears
1343-418: A seat tube angle around 73 degrees, with a head tube angle of anywhere from 60 to 73 degrees. The intended application of the bike affects its geometry very heavily. In general, steeper angles (closer to 90 degrees from the horizontal) are more efficient for pedaling up hills and make for sharper handling. Slacker angles (leaning farther from the vertical) are preferred for high speeds and downhill stability. In
1422-509: A single lever, or a pair of levers, or a twist grip ; some shifters may be incorporated with brake levers into a single unit. When a rider operates the shifter while pedalling , the change in cable tension moves the chain-guide from side to side, "derailing" the chain onto different sprockets. The rear derailleur also has spring-mounted jockey wheels which take up any slack in the chain. Most hybrid, touring, mountain, and racing bicycles are equipped with both front and rear derailleurs. There are
1501-429: A single number which allows the gearing of any bicycles to be compared regardless of drive wheel diameter; the numbers produced by different methods are not comparable, but for each method the larger the number the higher the gear. The third method, gain ratio, also takes the length of the crankarm into account, which can vary from bike to bike. The fourth method uses two numbers and is only useful in comparing bicycles with
1580-467: A slightly less efficient gear ratio when this leads to greater human efficiency (in converting food to pedal power) because a more effective pedalling speed is being used. An encyclopedic overview can be found in Chapter 9 of "Bicycling Science" which covers both theory and experimental results. Some details extracted from these and other experiments are provided in the next subsection, with references to
1659-502: A small number of sprockets, e.g. chainrings 44-48 and cogset 14-17-20-24-28. The effect is to provide two interlaced gear ranges without any duplication. However to step sequentially through the gear ratios requires a simultaneous front and rear shift on every other gear change. There are three chainrings with half-step differences between the larger two and multi-range differences between the smaller two, e.g. chainrings 24-42-46 and cogset 12-14-16-18-21-24-28-32-36. This general arrangement
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#17327868835891738-400: A step of 15% corresponds to a 2-tooth change from a 13-tooth sprocket to a 15-tooth sprocket. By contrast, car engines deliver power over a much larger range of speeds than cyclists' legs do, so relative differences of 30% or more are common for car gearboxes. On a bicycle with only one gear change mechanism (e.g. rear hub only or rear derailleur only), the number of possible gear ratios is
1817-405: A very diagonal chain alignment which is inefficient and causes excessive chain wear. Due to the overlap, there will usually be some duplicates or near-duplicates, so that there might only be 16 or 18 distinct gear ratios. It may not be feasible to use these distinct ratios in strict low-high sequence anyway due to the complicated shifting patterns involved (e.g. simultaneous double or triple shift on
1896-756: Is a type of bicycle with a single gear ratio and a freewheel mechanism. These bicycles are without derailleur gears, hub gearing or other methods for varying the gear ratio of the bicycle. Adult single-speed bicycles typically have a gear ratio of between 55 and 75 gear inches, depending on the rider and the anticipated usage. There are many types of modern single speed bicycles; BMX bicycles , some bicycles designed for (younger) children, cruiser type bicycles , classic commuter bicycles , unicycles , and bicycles designed for track racing . Fixed-gear road bicycles and fixed-gear mountain bicycles are also usually single speed in that they typically do not have any gear ratio adjustment. However, fixed gear bicycles do not have
1975-410: Is accomplished by using your foot to tap a button protruding on each side of the bottom bracket spindle. The effect is that of having a bicycle with twin chainrings with a massive difference in sizes. Pinion GmbH introduced in 2010 an 18 speed gearbox model, offering an evenly spaced 636% range. This gearbox is actuated by traditional twist shifter and uses two cables for gear changing. The Pinion system
2054-437: Is especially noticeable when cycling on roads and hard trails. At first, early rear suspension designs were overly heavy, and susceptible either to pedaling-induced bobbing or lockout. Most new mountain bikes use disc brakes. They offer much improved stopping power (less lever pressure is required providing greater braking modulation) over rim brakes under all conditions especially adverse conditions, because they are located at
2133-760: Is however still known for the heat and the rough terrain of the Australian Outback. The race was originally intended to take place in Vietnam . The event would last 18 days, starting in Saigon and finishing in Hanoi . But after spending two weeks in Vietnam race organisers Gerhard Schönbacher realized it was not possible to organise the event in Vietnam. Later on he found an alternative in Darwin and decided that
2212-440: Is more important than the absolute difference between gears. This relative change, from a lower gear to a higher gear, is normally expressed as a percentage, and is independent of what system is used to measure the gears. Cycling tends to feel more comfortable if nearly all gear changes have more or less the same percentage difference. For example, a change from a 13-tooth sprocket to a 15-tooth sprocket (15.4%) feels very similar to
2291-461: Is often used for bicycles intended for city-riding and commuting. Current systems have gears incorporated in the crankset or bottom bracket . Patents for such systems appeared as early as 1890. The Schlumpf Mountain Drive and Speed Drive have been available since 2001. Some systems offer direct drive plus one of three variants (reduction 1:2.5, increase 1.65:1, and increase 2.5:1). Changing gears
2370-405: Is preferable depends on the particular circumstances. There are a few other relatively uncommon types of gear change mechanism which are briefly mentioned near the end of this section. Derailleur mechanisms can only be used with chain drive transmissions, so bicycles with belt drive or shaft drive transmissions must either be single speed or use hub gears. External gearing is so called because all
2449-458: Is suitable for touring with most gear changes being made using the rear derailleur and occasional fine tuning using the two large chainrings. The small chainring (granny gear) is a bailout for handling steeper hills, but it requires some anticipation in order to use it effectively. Internal gearing is so called because all the gears involved are hidden within a wheel hub. Hub gears work using internal planetary, or epicyclic, gearing which alters
Crocodile Trophy - Misplaced Pages Continue
2528-462: Is that the overlapping gear ranges result in a lot of duplication or near-duplication of gear ratios. This style is commonly found on racing bicycles with two chainrings. The relative step on the chainrings (say 35%) is typically around three or four times the relative step on the cogset (say 8% or 10%), e.g. chainrings 39-53 and close-range cogsets 12-13-14-15-16-17-19-21 or 12-13-15-17-19-21-23-25. This arrangement provides much more scope for adjusting
2607-439: Is the aspect of a bicycle drivetrain that determines the relation between the cadence , the rate at which the rider pedals, and the rate at which the drive wheel turns. On some bicycles there is only one gear and, therefore, the gear ratio is fixed , but most modern bicycles have multiple gears and thus multiple gear ratios. A shifting mechanism allows selection of the appropriate gear ratio for efficiency or comfort under
2686-674: Is used in the ETRTO tire and rim sizing system), and the average 29″ mountain bike tire is (in ISO notation) 59-622 corresponds to an outside diameter of about 29.15 inches (740 mm). 622 mm wheels are standard on road bikes and are commonly known as 700C. In some countries, mainly in Continental Europe , 700C (622 mm) wheels are commonly called 28 inch wheels. 24 inch wheels are used for dirt jumping bikes and sometimes on freeride bikes, rear wheel only, as this makes
2765-451: Is well suited for mountain bicycles due to its wide range and low gravity center suitable for full-suspension bikes, but it is still somewhat heavier than derailleur-based drivetrain. It is sometimes possible to combine a hub gear with deraileur gears. There are several commercially available possibilities: There have been, and still are, some quite different methods of selecting a different gear ratio: The numbers in this section apply to
2844-559: The FMB World Tour and the Red Bull Rampage . Mountain bikes can usually be divided into four broad categories based on suspension configuration: Since the 1980s, mountain bikes have had anywhere from 7 to 36 speeds, with 1 to 4 chain-rings on the crankset and 5 to 12 sprockets in the cogset . 30-speed, 33-speed and 36-speed mountain bikes were originally found to be unworkable, as the mud-shedding capabilities of
2923-411: The 1.90 to 2.10 in (48 to 53 mm ) size, to 2.35 and 3.00 in (60 and 76 mm) widths popular with freeride and downhill bicycles. Although heavier wheelsets are favored in the freeride and downhill disciplines, advances in wheel technology continually shave weight off strong wheels. This is highly advantageous as rolling weight greatly affects handling and control, which are very important to
3002-413: The 27.5-inch wheel diameter with ≈2.25 widths (ISO 584 mm rim diameter), particular on smaller frame sizes for shorter riders. Mountain bikes with 24-inch wheels are also available, sometimes for dirt jumping, or as a junior bike. Bicycle wheel sizes are not precise measurements: a 29-inch mountain bike wheel with a 622 millimetres (24.5 in) bead seat diameter (the term, bead seat diameter (BSD),
3081-748: The acronym "ATB" are used as synonyms for "mountain bike", but some authors consider them passé. The original mountain bikes were modified heavy cruiser bicycles used for freewheeling down mountain trails. The sport became popular in the 1970s in Northern California, USA, with riders using older, single-speed balloon tire bicycles to ride down rugged hillsides. These modified bikes were called "ballooners" in California, "klunkers" in Colorado, and "dirt bombers" in Oregon. Joe Breeze ,
3160-441: The bike more maneuverable. 29 inch wheels were once used for only cross country purposes, but are now becoming more commonplace in other disciplines of mountain biking. A mountain bike with 29″ wheels is often referred to as a 29er , and a bike with 27.5-inch wheels is called a 27.5 Mountain bike or as a marketing term ″650B bike". Wheels come in a variety of widths, ranging from standard rims suitable for use with tires in
3239-574: The careful choice of chainrings and rear cogsets, e.g. 3 chainrings 48-34-20 and a 10-speed cassette 11–32, one can achieve an extremely wide range of gears that are still well spaced. This sort of setup has proven useful on a multitude of bicycles such as cargo bikes, touring bikes and tandems. Even higher gear ranges can be achieved by using a 2-speed bottom bracket hub gear in conjunction with suitable derailleurs. There are two main types of gear change mechanisms, known as derailleurs and hub gears. Both systems have advantages and disadvantages , and which
Crocodile Trophy - Misplaced Pages Continue
3318-499: The cassette. Due to the time and cost involved in such a product, they were only aimed at top-end XC-racers. However, 10-speed has become the norm by 2011 and the market leader Shimano even offers its budget groupset "Alivio" in a 10-speed version. In July 2012, SRAM announced a 1×11 drivetrain called XX1 that does not make use of a front derailleur for lighter weight and simplicity. In the 2014 Commonwealth Games at Glasgow all leading riders used 1×11 drivetrains. SRAM's new 1×12 gearing
3397-443: The center of the wheel (on the wheel hub). They therefore remain drier and cleaner than wheel rims, which are more readily soiled or damaged. The disadvantage of disc brakes is their increased cost and often greater weight. Disc brakes do not allow heat to build up in the tires on long descents; instead, heat builds up in the rotor, which can become extremely hot. There are two different kinds of disc brakes: hydraulic, which uses oil in
3476-566: The development of the sport of mountain biking in the 1970s, many new subtypes of mountain biking have developed, such as cross-country (XC) , trail , all-mountain , enduro , freeride , downhill , and a variety of track and slalom types. Each of these place different demands on the bike, requiring different designs for optimal performance. MTB development has led to an increase in suspension travel, now often up to 8 inches (200 mm), and gearing up to 13 speed, to facilitate both climbing and rapid descents. Advances in gearing have also led to
3555-433: The difference between bottom gear and top gear, and provides some measure of the range of conditions (high speed versus steep hills) with which the gears can cope; the strength, experience, and fitness level of the cyclist are also significant. A range of 300% or 3:1 means that for the same pedalling speed a cyclist could travel 3 times as fast in top gear as in bottom gear (assuming sufficient strength, etc.). Conversely, for
3634-482: The efficiency of belt drives and infinitely variable gear systems; even the manufacturers/suppliers appear reluctant to provide any numbers. Derailleur type mechanisms of a typical mid-range product (of the sort used by serious amateurs) achieve between 88% and 99% mechanical efficiency at 100 W. In derailleur mechanisms the highest efficiency is achieved by the larger sprockets. Efficiency generally decreases with smaller sprocket and chainring sizes. Derailleur efficiency
3713-558: The efficiency of the drive-train, including means of transmission and any gearing system. In this context efficiency is concerned with how much power is delivered to the wheel compared with how much power is put into the pedals. For a well-maintained transmission system, efficiency is generally between 86% and 99%, as detailed below. Factors besides gearing which affect performance include rolling resistance and air resistance: Human factors can also be significant. Rohloff argues that overall efficiency can be improved in some cases by using
3792-589: The finish line at each stage will score points that count toward the Points classification. The rider who holds the most points will wear a special jersey. Mountain bike A mountain bike ( MTB ) or mountain bicycle is a bicycle designed for off-road cycling. Mountain bikes share some similarities with other bicycles, but incorporate features designed to enhance durability and performance in rough terrain, which often makes them heavier, more complex and less efficient on smooth surfaces. These typically include
3871-504: The first route of the Crocodile Trophy would run from Darwin to Cairns . The race's route would change every year. The Crocodile Trophy's leaders jersey is awarded after each stage to the rider with the lowest overall time. The rider who has the lowest overall time will wear the jersey at the next stage. The cyclist who is awarded the jersey after the final stage is the overall winner of the race. The first five riders to cross
3950-495: The front and rear wheel are fitted with a shock absorber in some form as the wheel attaches to the bike. This provides a smoother ride as the front and rear wheels can now travel up and down to absorb the force of obstacles striking the tires. Dual suspension bikes of a similar quality are considerably more expensive, but this price increase brings an enormous off-road performance upgrade as dual suspension bikes are much faster on downhill and technical/rough sections, than other forms of
4029-422: The gear ratio is closely related to the mechanical advantage of the drivetrain of the bicycle. On single-speed bicycles and multi-speed bicycles using derailleur gears , the gear ratio depends on the ratio of the number of teeth on the crankset to the number of teeth on the rear sprocket ( cogset ). For bicycles equipped with hub gears , the gear ratio also depends on the internal planetary gears within
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#17327868835894108-411: The gear ratio to maintain a constant pedalling speed , but any change of chainring must be accompanied by a simultaneous change of 3 or 4 sprockets on the cogset if the goal is to switch to the next higher or lower gear ratio. This term has no generally accepted meaning. Originally it referred to a gearing arrangement which had one especially low gear (for climbing Alpine passes); this low gear often had
4187-403: The hardtail design has the benefits of lower cost, less maintenance, and better pedaling efficiency, it is slowly losing popularity due to improvements in full suspension designs. Front fork suspensions are now available with 8 inches (200 mm) of travel or more (see above under Designs .) Many new mountain bikes integrate a "full suspension" design known as dual suspension, meaning that both
4266-600: The hub. For a shaft-driven bicycle the gear ratio depends on the bevel gears used at each end of the shaft. For a bicycle to travel at the same speed, using a lower gear (larger mechanical advantage) requires the rider to pedal at a faster cadence, but with less force. Conversely, a higher gear (smaller mechanical advantage) provides a higher speed for a given cadence, but requires the rider to exert greater force or stand while pedalling. Different cyclists may have different preferences for cadence, riding position, and pedalling force. Prolonged exertion of too much force in too high
4345-494: The ideal of consistent relative differences, e.g. the Rohloff Speedhub offers 14 speeds with an average relative difference of 13.6% and individual variations of around 0.1%. Racing cyclists often have gears with a small relative difference of around 7% to 10%; this allows fine adjustment of gear ratios to suit the conditions and maintain a consistent pedalling speed. Mountain bikes and hybrid bikes often have gears with
4424-399: The largest sprocket which has roughly a 30% difference; this provides a much lower gear than normal at the cost of a large gearing jump. There are two chainrings whose relative difference (say 10%) is about half the relative step on the cogset (say 20%). This was used in the mid-20th century when front derailleurs could only handle a small step between chainrings and when rear cogsets only had
4503-440: The lines to push the brake pads against the rotors to stop the bike. They cost more but work better. Mechanical, which uses wires in the lines to pull the pads against the rotors. Typical features of a mountain bike are very wide tyres. The original 26 inch wheel diameter with ≈2.125″ width ( ISO 559 mm rim diameter) is increasingly being displaced by 29-inch wheels with ≈2.35″ width (ISO 622 mm rim diameter), as well as
4582-535: The mountain bike. This is because when the wheel strikes an obstacle its tendency is to bounce up. Due to some forward energy being lost in the upward movement some speed is lost. Dual suspension bikes solve this problem by absorbing this upward force and transmit it into the shocks of the front and rear wheels, drastically decreasing the translation of forward momentum into useless upward movement. Disadvantages of rear suspension are increased weight, increased price, and with some designs, decreased pedaling efficiency, which
4661-491: The original reports. Factors which have been shown to affect the drive-train efficiency include the type of transmission system (chain, shaft, belt), the type of gearing system (fixed, derailleur, hub, infinitely variable), the size of the sprockets used, the magnitude of the input power, the pedalling speed, and how rusty the chain is. For a particular gearing system, different gear ratios generally have different efficiencies. Some experiments have used an electric motor to drive
4740-478: The past mountain bikes had a rigid frame and fork. In the early 1990s, the first mountain bikes with suspension forks were introduced. This made riding on rough terrain easier and less physically stressful. The first front suspension forks had about 1 1 ⁄ 2 to 2 inches (38 to 50 mm) of suspension travel. Once suspension was introduced, bikes with front suspension and rigid, non-suspended rear wheels, or "hardtails", became popular nearly overnight. While
4819-494: The prevailing circumstances: for example, it may be comfortable to use a high gear when cycling downhill, a medium gear when cycling on a flat road, and a low gear when cycling uphill. Different gear ratios and gear ranges are appropriate for different people and styles of cycling. A cyclist's legs produce power optimally within a narrow pedalling speed range, or cadence. Gearing can be optimized to use this narrow range as efficiently as possible. As in other types of transmissions ,
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#17327868835894898-412: The rear derailleur and a single shift on the front derailleur). In the worst case there could be only 10 distinct gear ratios, if the percentage step between chainrings is the same as the percentage step between sprockets. However, if the most popular ratio is duplicated then it may be feasible to extend the life of the gear set by using different versions of this popular ratio. The gearing range indicates
4977-411: The relative step sizes between the front chainrings and the rear cogset. This style is commonly found on mountain, hybrid, and touring bicycles with three chainrings. The relative step on the chainrings (say 25% to 35%) is typically around twice the relative step on the cogset (say 15%), e.g. chainrings 28-38-48 and cogset 12-14-16-18-21-24-28. Advantages of this arrangement include: One disadvantage
5056-419: The relative values for gear inches, metres of development, gain ratio, and speed are more or less correct, while the front/rear values are the nearest approximation which can be made using typical chainring and cogset sizes. Note that bicycles intended for racing may have a lowest gear of around 45 gear inches (3.6 meters), or 35 gear inches (2.8 meters) if fitted with a compact crankset). A single-speed bicycle
5135-421: The rider to quickly adjust the seat height (an elevated seat position is more effective for pedaling, but poses a hazard in aggressive maneuvers). Mountain bikes are generally specialized for use on mountain trails, single track , fire roads , and other unpaved surfaces. In addition to being used to travel and recreate on those surfaces, many people use mountain bikes primarily on paved surfaces; some may prefer
5214-469: The same as the number of usable gear ratios , which is also the same as the number of distinct gear ratios . On a bicycle with more than one gear change mechanism (e.g. front and rear derailleur), these three numbers can be quite different, depending on the relative gearing steps of the various mechanisms. The number of gears for such a derailleur equipped bike is often stated simplistically, particularly in advertising, and this may be misleading. Consider
5293-407: The same drive wheel diameter. In the case of road bikes, this is usually around 670 mm. A 700c "standard" wheel has a 622 mm rim diameter. The final wheel diameter depends on the specific tire but will be approximately 622 mm plus twice the tire width. Front/rear measurement only considers the sizes of a chainring and a rear sprocket. Gear inches and metres of development also take
5372-533: The same intended application, more expensive tires tend to be lighter and have less rolling resistance. Sticky rubber tires are now available for use on freeride and downhill bikes. While these tires wear down more quickly, they provide greater traction in all conditions, especially during cornering. Tires and rims are available in either tubed or tubeless designs, with tubeless tires recently (2004) gaining favor for their pinch flat resistance. Tires also come with tubes, tubeless and tubeless-ready. Tires with tubes are
5451-758: The same pedalling effort, a cyclist could climb a much steeper hill in bottom gear than in top gear. The overlapping ranges with derailleur gears mean that 24 or 27 speed derailleur gears may only have the same total gear range as a (much more expensive) Rohloff 14-speed hub gear. Internal hub geared bikes typically have a more restricted gear range than comparable derailleur-equipped bikes, and have fewer ratios within that range. The approximate gear ranges which follow are merely indicative of typical gearing setups, and will vary somewhat from bicycle to bicycle. Gear ranges of almost 700% can be achieved on derailleur setups, though this may result in some rather large steps between gears or some awkward gear changes. However, through
5530-410: The shaft to which the pedals are attached, while others have used averages of a number of actual cyclists. It is not clear how the steady power delivered by a motor compares with the cyclic power provided by pedals. Rohloff argues that the constant motor power should match the peak pedal power rather than the average (which is half the peak). There is little independent information available relating to
5609-423: The size of the rear wheel into account. Gain ratio goes further and also takes the length of a pedal crankarm into account. Gear inches and metres of development are closely related: to convert from gear inches to metres of development, multiply by 0.08 (more precisely: 0.0798, or exactly: 0.0254 · π). The methods of calculation which follow assume that any hub gear is in direct drive. Multiplication by
5688-487: The speed of the hub casing and wheel relative to the speed of the drive sprocket. They have just a single chainring and a single rear sprocket, almost always with a straight chain path between the two. Hub gears are available with between 2 and 14 speeds; weight and price tend to increase with the number of gears. All the advertised speeds are available as distinct gear ratios controlled by a single shifter (except for some early 5-speed models which used two shifters). Hub gearing
5767-426: The sprockets involved are readily visible. There may be up to 4 chainrings attached to the crankset and pedals, and typically between 5 and 12 sprockets making up the cogset attached to the rear wheel. Modern front and rear derailleurs typically consist of a moveable chain-guide that is operated remotely by a Bowden cable attached to a shifter mounted on the down tube, handlebar stem, or handlebar. A shifter may be
5846-889: The standard design and the easiest to use and maintain. Tubeless tires are significantly lighter and often have better performance because you can run them at a lower tire pressure which results in better traction and increasing rolling resistance. Tubeless-ready tires are tires that can use tubes or go tubeless. A liquid sealant is used without the tube to secure the seal to the rim. Popular tire manufacturers include Wilderness Trail Bikes , Schwalbe, Maxxis, Nokian, Michelin, Continental, Tioga, Kenda, Hutchinson, Specialized and Panaracer. Mountain bikes are available in tandem configurations. For example, Cannondale and Santana Cycles offer ones without suspension, while Ellsworth , Nicolai, and Ventana manufacture tandems with full suspension. [REDACTED] Media related to Mountain bikes at Wikimedia Commons Bicycle gearing Bicycle gearing
5925-686: The technical nature of freeride and downhill riding. The widest wheel/tire widths, typically 3.8 in (97 mm) or larger, are sometimes used by icebikers who use their mountain bikes for winter-time riding in snowy conditions. Manufacturers produce bicycle tires with a wide variety of tread patterns to suit different needs. Among these styles are: slick street tires, street tires with a center ridge and outer tread, fully knobby, front-specific, rear-specific, and snow studded. Some tires can be specifically designed for use in certain weather (wet or dry) and terrain (hard, soft, muddy, etc.) conditions. Other tire designs attempt to be all-around applicable. Within
6004-443: The ubiquity of "1x" drivetrains (pronounced "one-by"), simplifying the gearing to one chainring in the front and a wide range cassette at the rear, typically with 9 to 12 sprockets . 1x gearing reduces overall bike weight, increases ground clearance, and greatly simplifies the process of gear selection, but 2- or 3-ring drivetrains are still common on entry-level bikes. The expressions "all terrain bicycle", "all terrain bike", and
6083-593: The upright position, plush ride, and stability that mountain bikes often have. Mountain biking terrain commonly has rocks, roots, loose dirt, and steep grades. Many trails have additional technical trail features (TTF) such as log piles , log rides , rock gardens , skinnies , gap jumps , and wall-rides . Mountain bikes are built to handle these types of terrain and features. The heavy-duty construction combined with stronger rims and wider tires has also made this style of bicycle popular with urban riders and couriers who must navigate through potholes and over curbs. Since
6162-430: Was introduced in 2016 as SRAM Eagle. This gives a single chain ring bike better ability to climb. The critical angles in bicycle geometry are the head angle (the angle of the head tube ), and the seat tube angle (the angle of the seat tube ). These angles are measured from the horizontal, and drastically affect the rider position and performance characteristics of the bicycle. Mountain bike geometry will often feature
6241-507: Was quoted in the New York Times saying I'd say these bikes are one of the biggest things that ever happened to the biking industry. Its basic look constitutes "a total shift in image" for the industry. Throughout the 1990s and 2000s, mountain biking moved from a little-known sport to a mainstream activity complete with an international racing circuit and a world championship , in addition to various free ride competitions, such as
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