Стандарты: Виды быстросъемных осей-эксцентриков для MTB колёс
Втулки на эксцентриках позволяют быстро снять колёса и не запариваться с наличием необходимого инструмента под рукой. И если вы думаете, что эксцентрики хлипкие и не стоят вашего внимания, то сегодня мы вас разубедим!
QR или Quick-release (от англ. Быстросъемный) – самый простой эксцентрик, который можно встретить на бюджетных велосипедах. Такие эксцентрики устанавливаются только на велосипедах с разрезными дропаутами. Из-за небольшого диаметра оси 9мм и 10мм соответственно для переднего и заднего колеса и диаметра самого эксцентрика 5мм жесткость у них соответствующая, однако для обычного катания это не критично. Своё предназначение такой эксцентрик выполняет на все 100% и позволяет быстро снимать и устанавливать колёса без проблем. Встречаются только в размерах 100мм и 135мм для переднего и заднего колеса соответственно.
Thru-axle
Thru-axle (от англ. Через ось) – имеют высокую жесткость и используются в велосипедах для агрессивного катания. Для заднего колеса выпускаются с шириной 135, 142, 150 и 157мм и диаметром 12 мм. Сама ширина втулки регулируется при помощи проставок сбоку и 135 легко превращается в 157мм без замены самой втулки. Для переднего с диаметром 15мм и 20мм и шириной 100мм и 110мм соответственно.
Такой эксцентрик вставляется в закрытый дропаут, что предотвращает возможность впадения колеса, пока эксцентрик закрыт. Хотя использования на раме с разрезными дропаутами не рекомендуется, но в отличие от вилки вы сможете физически установить такое колесо на раму.
Boost thru-axle
Недавно пришедший на рынок стандарт, заточенный исключительно под модное эндуро. Втулки выпускаются только в размерах 15*110мм и 12*148мм для переднего и заднего колеса. Как водится у нас в индустрии, задняя втулка вышла с новой линейкой шатунов, для более правильного чейнлайна, а добавление 10мм на передней втулке позволило сделать жесткость 27.5 колёс такой же, как и у 26. Во всяком случае так заверяют производители. На самих втулках выросло расстояние между фланцами, а не толщина боковых проставок.
Вот такие эксцентрики присутствуют на рынке сейчас, надеемся эта статья поможет вам не запутаться.
Что такое эксцентрик для велосипеда
Велосипедисту регулярно приходится проводить обслуживание своего велобайка, поэтому важно понимать, чем проще будет механизм разборки, тем быстрей и легче будет весь процесс. При установке некоторых деталей можно выкроить для владельца велосипеда несколько минут, а иногда и сэкономить средства на покупку новых. Например, такая незначительная деталь, как эксцентрик. Это очень удобная вещь и даже новичку с простеньким велотранспортом стоит разобраться, что такое эксцентрик для велосипеда и его разновидности. Поэтому стоит уделить время на данную статью, дабы выяснить все тонкости.
Устройство и принцип действия велоэксцентрика
Эксцентриком называется механизм, закрепляющий ось на велосипеде. Существует три места применения: на втулке, на подседельной трубе и точки соединения элементов складного велотранспорта.
Чаще всего велоэксцентрик используется для крепежа втулки на дропаутах рамы велосипеда. Механизм может применяться как для передних колес, так и для задних, соответственно конструкция может немного изменяться.
Устройство
Конструкция эксцентрика представляет собой высокопрочную ось, вставленную в зажимную ручку с уплотнительной резинкой, с одной стороны, чаще всего поверх последней одета чаша. Посередине две пружинки, надетые на ось (пружинки используются для велоэксцентрика, устанавливаемого на втулках колеса) и колпачок с насечками, который накручивается с другой стороны. Данная конструкция является наиболее распространенной, но может изменяться в зависимости от разновидности, в соответствии с этим на ось одевают дополнительные детали.
Положительные стороны
Велоэксцентрик обрел популярность на современных велосипедах, так как превосходит в удобстве крепежа по сравнению с гаечным. При этом качество ничем не хуже, но при условии, что эксцентрик исправен и находится в хорошем состоянии.
Удобство использования данной конструкции особенно ощущается в поездках на велосипеде. Когда нужно разблокировать велоколесо, то его можно легко снять, без использования ключей для раскручивания гаек. Последние в течение времени прикипают и открутить становится проблематично и понадобится время, а в будущем потребуется замена на новые.
Отрицательные стороны
При всех достоинствах механизма, существует и обратная сторона:
Виды и основные характеристики
Различают несколько разновидностей велоэксцентриков, в зависимости от места крепления на велотранспорте, материала изготовления и размера. Но все они имеют одинаковый принцип действия. Чаще всего изделие изготавливают из хромолибденового или титанового сплава.
Эксцентрик quick-release (QR)
Знающие английский язык поймут из названия — быстросъемный эксцентрик. Является наиболее применяемым. Ставится на велосипеды низко-среднего ценового сегмента.
Особенность заключается в том, что ставится он на велосипеды с разрезными дропаутами, так как диаметр оси составляет 10 мм переднего колеса и 9 мм заднего, а диаметр требуемого велоэксцентрика 5 мм. Такой велосипед предназначен для обычного катания, и этого значения более чем достаточно. QR-эксцентрик для велобайка изготавливают длиной 100 мм и 135 мм.
Thru-axle велоэксцентрик
Данный вид велоэксцентрика ранее устанавливали исключительно на колесах велотранспорта, используемого в агрессивных заездах, в современных реалиях на подавляющем большинстве велотехники средне-высокого ценового сегмента. Так как на колеса приходится большое давление, то и ось должна выдерживать соответствующую нагрузку. Данная конструкция эксцентрика ставится в дропауты закрытого типа, дабы при езде не было люфтов колеса.
Переднее велоколесо имеет длину втулки 100 мм и 110 мм с соответствующим диаметром 15 мм. и 20 мм.
Заднее имеет параметры длины в 135, 142, 150, 157 мм., чему соответствует диаметр 12 мм. При помощи велоэксцентрика ширину втулки можно увеличить с 135 мм на 157 мм., добавлением проставок.
Boost thru-axle
Данный стандарт используется для владельцев велосипедов, катающихся в стиле эндуро. Втулки имеют четкие размерные стандарты длины — 148 мм. с диаметром 12 мм. и 110 мм на 15 мм.
Производители утверждают, что повысилась жесткость переднего велоколеса, так как втулка на 10 мм. стала шире. Ширина изменилась за счет увеличения расстояния между фланцами.
Как установить колесо на велоэксцентрике
Установку колеса, независимо от того, переднее оно или заднее, нужно проводить предварительно перевернув велотранспорт вниз рулем или закрепив в монтажной стойке.
В таком положении хороший доступ к эксцентрику и исключено выпадение колеса из разрезанного дропаута рамы велобайка:
Проверку надежности зажима лучше всего проводить на месте. Ее делают таким образом: задняя часть велобайка приподнимается и резко отпускается, чтобы колесо слегка подпрыгнуло от пола. После чего велоколесо прокручивают с силой, шатания колеса между дропаутами быть не должно.
Итоги
Легкие в использовании и практичные велоэксцентрики доказали свое преимущество перед креплением при помощи гаек. Во время установки эксцентрика на велосипед не возникает трудностей с отсутствием инструмента, что существенно облегчает ремонт при длительном заезде. А разобраться в конструкции механизма с целью поддержания его в надлежащем состоянии, не составит труда даже неопытному владельцу велобайка. Если использовать велоэксцентрик правильно, то он прослужит длительное время верой и правдой.
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Thru axle что это
Объясните плз (или дайте линк на подробное описание) принципы крепления втулок.
Хочу взять себе Hadley.
Бывает диаметр оси задней втулки 12мм, а бывает 10мм, нужна такая, которая подходит к Вашим задним дропаутам на раме.
помимо «толщины» оси, ещё бывает её «длина», 135мм или 150мм.
В основном бывают 135мм х 10мм и 150мм х 12мм, но бывает и 135мм х 12.
PS
А на счет крепления втулки, т.е. «болт» или «ось» это лишь конструктивные особенности конструкции, главное чтобы втулка подходила к дропаутам.
У меня на dropout size стоит vertical.
http://www.bikepedia.com/QuickBike/BikeSpe. &Type=frame (http://www.bikepedia.com/QuickBike/BikeSpecs.aspx?Year=2008&Brand=Niner&Model=S.I.R.+9+frame&Type=frame)
У меня на dropout size стоит vertical.
http://www.bikepedia.com/QuickBike/BikeSpe. &Type=frame (http://www.bikepedia.com/QuickBike/BikeSpecs.aspx?Year=2008&Brand=Niner&Model=S.I.R.+9+frame&Type=frame)
У меня на dropout size стоит vertical.
http://www.bikepedia.com/QuickBike/BikeSpe. &Type=frame (http://www.bikepedia.com/QuickBike/BikeSpecs.aspx?Year=2008&Brand=Niner&Model=S.I.R.+9+frame&Type=frame)
Добавлено позже (13/04/2008 20:24):
Что за 72 engagement, брать его или 36 engagement?[/b]
Количество щелчков, характеризует величину свободного хода (чтобы получить свободный ход в градусах, дели 360 на 72 и 36, соответственно). По идее, чем больше щелчков, тем лучше.
Добавлено позже (13/04/2008 20:26):
Привет всем.
Тут вырос по идее нубский вопрос. просто совершенно не интересовался подобными вопросами. facepalm:
В общем
Тут друг спросил меня по теме кросс-кантри.
Он сейчас хочет сменить колесо переднее и на будущее прицелится купить вилку. И хочет сразу понять, какого стандарта втулку ему брать, чтобы все подошло позже.
Вилка нужна ходом 100мм(была какая то простенькая тора)
В основном присмотрелись к какой нибудь фокс 32 бу в районе 10 т.р. (также смотрел пайк, вроде там какие то ревелейшн, рекон, реба, но в них я вообще хз)
какие там оси в вилках сейчас? 9, 15 мм? Там вроде какие то стандарты свои или хз.
вообще честно говоря даже не представляю что за ось у меня в тотеме и в аргайле))))):mrgreen:
собстна такой разрозненно-общий вопрос)))
спасибо за помощь):)
по теме кросс-кантри
В кросскантри не используют вилки/втулки под ось, используют под эксцентрик, а он 9мм. Оси 15 и 20мм используются для других дисциплин и для более сурового катания.
что за ось у меня в тотеме и в аргайле
Должна быть 20мм.
ха. мне кажется или тема исчерпана?
т.е. друг покупает втулку под ось 9 мм и потом свододно покупает любую вилку из тех же фоксов 32. правильно я все понял?
спасибо большое))но если будут еще комментарии пишите)
Понял спасибо)
другу передам)
про штоки проще)
и спасибо модераторам за перенос темы)не увидел)
Thru Axle Vs Quick Release: Pros and Cons
Posted on Last updated: October 3, 2021
Home » Bikes and Cycling » Thru Axle Vs Quick Release: Pros and Cons
Thru axles are becoming increasingly popular these days. Over the past 10 years, they have pretty much become the standard on mountain bikes. Now, more and more touring and road bike manufacturers are making the switch. After some research and testing, I created this thru axle vs quick release pros and cons guide to help you decide which axle style is best for your next bike. I’ll also explain the difference between both systems and outline thru axle sizing.
What Are Thru Axles?
Thru axles are a wheel attachment system. They secure the hubs between the dropouts in the frame and fork. Thru axle dropouts have holes, rather than slots. The thru axle itself is a thick, solid pin that is threaded on one end. It inserts from the side of the wheel.
After threading through one dropout and the hub, the thru axle screws into the far dropout. This way, the wheels are essentially bolted to the frame and fork. The thru axle secures in place with a cam lever or hex bolt on the end that tensions the axle so it doesn’t come loose. There are no slots so the axle must be removed completely in order to remove the wheel from the bike.
Standard front thru axles measure 15 mm in diameter and the rear measures 12 mm. Different lengths are available to fit different hub spacing. I’ll talk more about thru axle sizes later.
What are Quick Release Axles?
Quick release axles are the standard wheel attachment system used on most bikes. They allow you to remove and replace the wheels quickly and without any tools. You don’t even need to remove the axle from the hub.
A quick release axle system is composed of a thin metal skewer that runs through the hubs. The skewer is held in place by an acorn nut on one side and a quick release cam lever on the other. Two small springs sit on either side of the hub.
The dropouts on a quick release frame and fork have u-shaped slots. The wheel secures to the bike by slotting the skewer into the u-shaped dropouts, slightly tightening the acorn nut, and clamping the quick release lever closed. A cam mechanism tensions the axle and holds the wheel in place with friction. The quick release axle stays in the hub when you remove the wheel.
Most quick release axes measure 5 mm or 9 mm in diameter. Various lengths are available to fit different hub spacing.
A Bit of Quick Release History
While racing through freezing weather in the Dolomites in November of 1927, Italian cyclist Tullio Campagnolo was slowed down by a stuck wingnut on his axle. He needed to remove the wingnut so he could remove his wheel to change gears. (At that time, bicycles had a sprocket on either side of the rear wheel. In order to change gears, you would remove the wheel and flip it around.) The misbehaving wingnut on Tullio’s bike cost him precious time which ended up costing him the race.
This experience inspired Tullio to develop a quick release wheel locking mechanism. This invention allowed cyclists to remove and replace their wheels in seconds. The quick release axle was patented in 1930 and became the standard for over 90 years. Tullio went on to patent numerous cycling and non-cycling inventions and founded the cycling company Campagnolo.
The Invention of Thru Axles
Tullio couldn’t anticipate the ever-increasing demands of downhill mountain bikers. During races, quick release axles began bending and breaking.
Quick release axle failure became particularly common on mountain bikes with disc brakes and suspension forks. The fork legs were not moving in unison when the suspension compressed and during braking. This resulted in poor brake rotor alignment, poor tracking in turns, and even detached wheels.
As axle failures grew more and more common in downhill mountain biking, it became evident that a more robust axle design was needed. In the early 2000s, thru axles were invented.
The axle was made thicker so it wouldn’t bend or break under stress. The dropouts were redesigned with holes so the wheel couldn’t detach. Thru axles bolt the fork legs together to reduce fork torsion from braking and uneven suspension loading. This creates a much stiffer front end, which improves handling and stability. The more robust design improves safety as well.
These days, quick release axles have pretty much been replaced by thru axles in competitive mountain biking. Road cyclists are in the process of adopting the technology as well.
Thru Axle Pros
1. Thru axles are safer- This is probably the biggest benefit for the average cyclist. Thru axles improve safety by making it nearly impossible for the front wheel to come out of the dropouts while you’re moving. The dropouts can’t lift off of the axles vertically because they have holes instead of a u-shaped slots. In other words, the dropout completely surrounds the axle. Thru axles also screw into the dropout, forming a much more secure connection.
This design prevents disc brakes from ejecting the axle under heavy braking force. Thru axles also make the fork more robust and less likely to fail. The axles themselves are unlikely to break because they are thicker and stronger. Finally, the axles are less likely to come loose after being improperly tightened. All of these features improve safety. I’ll outline each point in more detail in this section.
2. Thru axles reduce brake rotor rub and improve braking force– When you stand up to pedal hard, the fork can flex. Sometimes it flexes enough that a disc brake pad rubs on the rotor. This is possible because disc brake pads rest just a couple of millimeters away from the rotor.
Brake rotor rub creates drag that slows you down and reduces efficiency. It’s also simply annoying because it makes a rubbing sound.
Thru axles eliminate this problem by reducing fork flex. They create a rigid connection between the hub and fork legs, which makes the whole front end structurally stronger. As an added benefit, braking performance marginally improves because the brake rotor stays better aligned in the caliper.
3. Thru axles don’t bend or break under heavy stress- Some disciplines of cycling put an enormous amount of stress on axles. This is the case with freeride and downhill mountain biking. Thin quick release axles can bend or break during a hard landing after a jump or drop.
This problem is particularly common on bikes with suspension forks. The legs compress unevenly and bend or break the axle. A bent axle can ruin a hub. If the axle breaks, the wheel can come off.
Thru axles, being 3-4 times thicker, have a much higher tensile strength. They don’t break under stress. The extra material greatly increases the axle’s strength, improving safety, handling, and braking. This problem is the reason why thru axles were invented in the first place.
4. Thru axles prevent disc brakes from ejecting the wheels- When disc brakes came into widespread use in mountain biking during the early 2000s, a safety issue with quick release axles became apparent. Cyclists found that heavy braking force created by disc brakes can eject a quick release axle out of a U-shaped dropout.
James Annan documented this issue in this old thread from 2003. You can also read about a few cyclists experience wheel ejection in this thread.
This phenomenon occurs because the braking force created by disc brakes pushes the wheel down and forward. This means the wheel wants to push itself out of the dropout every time you brake. After repeatedly braking, the QR axle can slowly loosen. If the axle gets loose enough, the wheel can eject out of the dropout. (Wheel ejection isn’t a problem on rim brake bikes because the braking force pushes the wheel back into the dropouts.)
Cyclists suggested a simple solution: to move the brake caliper to the front of the fork arms. This would change the direction of the braking force so the wheels don’t want to push themselves out. Manufacturers instead decided to change the orientation of the dropout slightly to reduce the risk.
Thru axles completely solve the disc brake wheel ejection problem altogether. Because the dropouts use holes instead of U-shaped slots, the axle can’t pull out vertically. For this reason, thru axles are a better choice for bikes with disc brakes.
5. Thru axles improve handling, cornering, and stability by stiffening the front end of the bike- This is the most significant performance enhancement. Thru axles bolt both fork arms together. This makes the bike’s front end structurally stronger. Fork flexing from powerful pedaling or torsional forces created by disc brakes is greatly reduced. The thru axle dropouts are also a bit beefier, which makes them more robust.
When the front end is stiffer, you can steer more accurately and precisely. The front wheel also tracks better while cornering when it is more rigidly attached to the bike. You can steer better while braking as well. Handling is better overall. The extra stiffness is particularly useful while hauling heavy loads while touring.
Thru axles also prevent suspension forks form compressing unevenly. Because the fork arms connect through the axle, both fork arms synchronize. Suspension forks absorb shocks better because they compress evenly. This improves stability and handling off-road, allowing you to navigate rough roads and technical terrain more easily. Mountain bikers benefit from this design.
6. Thru axles prevent fork fatigue and failure- When you apply the front disc brake, the fork wants to twist and flex. The reason is that disc brake calipers and rotors mount on one side of the wheel. Braking creates a torsional force, causing the fork to flex. Over time, this flexing can cause the fork to fatigue and eventually fail. Thru axles bolt the fork legs together. This makes the fork much more resistant to torsion forces than a quick release.
7. More consistent wheel alignment when removing and replacing the wheel- When you put your quick release wheel in the u-shaped dropouts, they don’t line up exactly the same every time. This is because the ridges on the quick release that bite into the frame to hold the hub in a slightly different position every time. There is some margin for error. Your wheel can end up slightly misaligned. This can lead to two issues.
First, your brake rotor or rim isn’t properly aligned. This can cause your brake pads to rub. Second, your cassette or freewheel can sit crooked if the rear wheel is misaligned. This can prevent your drivetrain from working smoothly. You might have to loosen then re-tighten the quick release to get the wheel to sit properly.
Thru axles solve these issues because the hubs sit in the dropouts exactly the same every time. There is no room for error.
8. Thru axles reduce injuries from user error- When replacing a wheel with a quick release axle, it would be easy to attach it too loosely. Particularly if you’re new to cycling. If this happens, the wheel could pop out unexpectedly. This mistake has caused many cycling injuries over the years. Thru axles greatly reduce the likelihood of human error. They are simple and intuitive to use.
9. Thru axles are more modern- These days, most mid-range to high-end road, touring, and mountain bikes come with thru axles instead of quick release. If you like to use the newest and most modern cycling equipment, thru axles are a good choice. I imagine over the next 10 years, most manufacturers will switch to thru axles, even on lower-end bikes.
Thru Axle Cons
Thru axle frames and forks also cost more than those designed for quick release because they are more complicated and time consuming to build. The axle holes in the dropouts must be perfectly aligned and sized for the wheels to roll straight. There is very little margin for error. It takes more man-hours and precision to build the frame. This may be worth considering if you’re having a frame custom built.
Frames with u-shaped dropouts for quick release axles are cheaper to make because they allow for more adjustibility during manufacture. There is more margin for error. They also take less time to build.
2. Thru axles are heavier than quick release- Standard thru axles weigh 60-80 grams each depending on the size. Quick release skewers weigh around 40-50 grams each.
There are lightweight thru axles available that are made of aluminum, titanium, or carbon fiber. These weigh about the same as quick release skewers but cost much more.
Thru axle frames and forks are also slightly heavier because it takes more material to wrap the dropouts completely around the axle. The extra metal adds a few grams to each dropout. The weight penalty is so minor that it would really only matter for weight weenies or those who ride competitively.
3. Parts are harder to find in some parts of the world- Thru axles are really only common on higher-end bikes. In much of the developing world, high-end bikes and components are not common. If you lose a thru axle or need a new hub, it may be hard to find a spare while traveling somewhere remote. Small town bike shops may not carry thru axles. You may need to travel to the nearest capital city or have parts shipped in. For this reason, bicycle tourists usually stick with quick release axles at this time.
Having said this, more and more touring bike manufacturers are switching to thru axles. For example, Surly’s new disc trucker has thru axles. The axles are also one of the least likely parts to fail while touring because they are so robust. With globalization, it is becoming easier and easier to have parts shipped in as well.
4. Removing a wheel takes more time with thru axles- You have to unscrew the axle and remove it from the bike completely. Removing a wheel takes a few seconds longer with thru axles than it does with quick release. There is also the possibility of losing the axle while it is removed because it does not stay in the hub.
This is really only a problem in racing. To solve this issue, many teams on The UCI World Tour have begun using a spare bike instead of swapping out wheels in the event of a puncture. For recreational riders, having to spend a few extra seconds here and there doesn’t really matter.
5. Thru axles are not compatible with some bike racks and work stands- Many racks secure the bike by slotting the front quick release dropout into the rack. You remove the front wheel, place the u-shaped dropout over a pin, and lock it in place with some kind of locking mechanism. This is particularly common on car rooftop bike racks.
With thru axles, these racks become obsolete. Thru axle bikes are not compatible due to the dropout’s circular design. If you transport your bike on one of these racks, you may need to buy a new one if you switch to quick release axles. Adapters are available for some models. For example, this Filzer Fork Adapter will work with most racks.
6. Thru axles are overkill for most riders- Most riders never have to worry about breaking a quick release skewer or having the skewer work its way loose. This kind of thing really only happens in racing or hardcore mountain biking where a considerable amount of stress is put on the bike.
Performance improvements with thru axles are marginal at best and aren’t really worth the cost or hassle of upgrading for most riders. Some riders aren’t even convinced that thru axles offer any benefits at all.
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Quick Release Axle Cons
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The Third Option: Bolt On Skewers (Solid Axles)
Bolt-on skewers work exactly the same as quick release skewers except they tighten with a bolt instead of a cam lever. They have the same diameter as QR. The bolt-on design allows you to tighten the axle tighter than you can with just your hand. Using a wrench or hex key to tighten the axle gives you more mechanical advantage.
Bolt on axles offer a few advantages over standard quick release. First, they make it less likely for your wheel to come off simply because they hold the wheel tighter. For this reason, many quick release disc brake bikes come with bolt-on skewers. They make it much less likely for the axle to loosen or the wheel to eject during hard braking.
Another benefit of bolt-on skewers is that they make it slightly harder for a criminal to steel your wheels. They would need a wrench to remove the bolt. They can’t just use their hand like they can with a lever. The bolt also looks a bit sleeker than the lever.
There are some disadvantages to bolt-on axles. First, you’ll have to carry a tool to take your wheels off. This adds a bit of weight to your tool kit. It also takes a few seconds longer to remove and replace the wheels. This can be annoying if you take your wheel with you when you park your bike to avoid theft.
Thru axles are also available with in both bolt on or lever options.
Thru Axle Sizes: Diameter, Length, and Thread Pitch
Three measurements define the size of a thru axle. The front and rear are almost always different sizes. When buying a replacement thru axles, you’ll need to know the following to ensure that you buy sizes that are compatible with your frame, fork, and hub.
Image: “Chris King Thru Axle”, by Glory Cycles, licensed under CC BY 2.0
Thru Axle Diameter
Front thru axles usually measure 15 mm in diameter. Rear thru axles usually measure 12 mm in diameter. This is the current standard. To measure the diameter, you can use a pair of calipers.
The front thru axle is larger in diameter than the rear because steering puts more torsion force on the axle. In the past, 20 mm thru axles were used on the fork. Downhill mountain bikers still use 20 mm axles on the front. Some road riders are switching to 12 mm front thru axles these days to cut weight.
Length
Thru axles come in a range of lengths to accommodate different hub spacing. Manufacturers use two different length dimensions to indicate the size:
When it comes to length, there you have about a 2-3 mm margin for error to work with. If the axle is slightly too short or long, it should still work.
Thread Pitch
Thread pitch is the distance from the tip of one thread to the tip of the next thread in milimeters. You can use a caliper to measure this. Common thru axle thread pitches include 1 mm, 1.5 mm and 1.75 mm. It’s important that you get the right thread pitch so you don’t strip your axle or dropout.
Mixing Thru Axles and Quick Release
You don’t need to use the same axle system on both wheels. For some riders, using a front thru axle and a rear quick release axle makes the most sense. This is worth considering for several reasons.
First is the cost. If you’re getting your frame custom built, it is cheaper and faster order it with a rear quick release and front thru axle. The reason is that it is harder for frame builders to keep thru axle dropouts aligned and there is less margin for error during manufacture. The frame takes more time to build which adds to the cost. Front thru axles don’t add any time or expense because there are plenty of thru axle forks on the market.
Next, rear thru axles provide very little if any benefit for most riders. Front thru axles are more important because the fork is weaker and more susceptible to flex than seat and chain stays. The front of the bike also steers. The strength of thru axles helps.
Finally, thru axles require longer chainstays because they use wider hub spacing than quick release. The standard rear dropout spacing for thru axles is 142 mm. If you combine this with 405 mm chainstays, your chain may run at too extreme of an angle while you’re using the outermost gears.
This means you won’t be able to cross chain gears by running the smallest chainring and smallest cog on the rear. Your heel could also rub on the wide chainstays while pedaling. With 142mm thru axles, you’ll want your chainstays to be at least 415-420 mm.
One interesting thing to note is that the rear dropout spacing is exactly the same for standard rear disc 135 mm quick release axles and 142 mm thru axles. Even though thru axles are longer, you end up with the same exact dropout width and cassette position because part of the thru axles sit inside of a pocket in the dropouts. This article has a great visual showing how this works.
Converting A Quick Release Bike to Thru Axles
If you’re in love with your frame but want to upgrade to thru axles, it is possible to make a conversion in some cases. There are a few ways to go about this. All involve swapping out some components.
The best and easiest solution is to swap out your quick release fork for a thru axle fork. In most cases, you will also need a new front hub that is compatible with thru axles. 15 mm is the most common diameter for front thru axles.
There are also adapters that allow you to use a thru axle hub in a quick release fork. I don’t have any experience with this. If you do, comment below.
For the rear, your best option is to swap out the quick release for a bolt-on axle. These use the same hub and drop out as quick release but provide a bit more secure connection between the wheel and frame.
You can’t upgrade the frame to thru axles without cutting off your dropouts and welding on new ones. At that point, you’re better off just buying a new frame.
Final Thoughts about Thru Axles Vs Quick Release
Some riders feel that thru axles are just a way for the industry to sell more bikes and components. There is probably some truth to this. The advantages they offer aren’t really noticeable for the average recreational cyclist.
Thru axles offer more benefits for mountain bike riders than road riders. The main advantage that everyone can enjoy is safety. Handling marginally improves as well.
Having said this, it seems like thru axles are where the industry is headed. The technology is simple, easy to use, and robust. Thru axles are definitely a step forward. Just not a big leap. If you’re happy with your quick release bike, there is no reason to go out and buy a new bike just so you can have thru axles. If you’re planning to upgrade anyway, thru axles are probably the better choice.
Where do you stand on the thru axle vs quick release debate? Share your tips and experience in the comments below!