For those who just start to get familiar with MTB, it’s quite difficult to read and understand the components and their specifications. What is this component? Where is this component stay in my bike? Why this component is fit to this bike but can’t be used for others? How can I know if this component fit to my bike? Those are repeated questions from many junior cyclists. That is the reason why Asama create the series of bike’s components articles. We hope you can find the usefulness from them. Now, let’s start with ‘MTB hubs’.
The position of hub is at the central of your bike wheels. It connects to the rim by spokes, helps the wheel to spin around the fixed bearing axle. Base on front and rear wheel, the front hub and rear hub are different. Front hub has simple design that focus on the function of spinning. Rear hub is more complicated. It’s directly assembled with cassette, join the driven activity and be a part of transmission system.
Front hub
There are 3 basic types of front hub:
1. Quick Release
Hub is 100mm length, it uses the small axle of 5mm diameter. QR Hub is usually used for entry-level MTB or old model of mid-level MTB, which apply for flat road and easy terrain road. By this type, you can snap on and snap off the wheel easily. You also can find the QR hub on the local bike shop easily with low cost.
However, in case you want to ride you bike more off-road or practice some professional technical skill, QR hub is not a good choice. The axle of QR is small, easily bent out of shape when standing a heavy force. If you don’t lock the QR hub carefully, you also can get the trouble of riding without front wheel.
2. 15mm Axle Hub
Hub is 100mm length, it uses the big axle of 15mm diameter. This type of hub can use QR or hexagon key to assemble and release. The axle usually goes with front fork. You can see this type on high-end level or new model of MTB. You can also use 5mm axle with switch heads. However, Asama suggest you to use the suitable axle with hub to get the maximum effectiveness.
To release the wheel, you have to take the axle out of fork completely. Therefore, it is safer when you ride off-road or do technical skill. In case the hub is loose assembled, the wheel is still fixed on frame. 15mm Axle Hub is high cost. And at current, there are few bike shops in Vietnam sell this type of hub.
3. Boost
Boost is the new technology applied on MTB recently. It is more and more popular and become the replacement of 100x15mm axle from year 2016. You can find that Boost is apply for most recent model of bike brands. The length of hub is widened 5mm for each side. The declination of spokes is increased, so the wheel is steadier.
In Vietnam bicycle market, Boost is a brand-new definition. You will find it’s very difficult to buy this type of hub in normal bike shop.
*If you would like to upgrade the front hub, you just have to change the front fork and still can keep the old frame. Each branded front fork has the specification of hub. You can base on that reference to buy the suitable one.
Rear hub
1. Quick Release
Hub is 135mm length, it uses the small axle of 5mm diameter. Basically, this type of hub is similar to front QR hub. It’s usually used in entry-level MTB or old model of mid-level MTB, which apply for flat road and easy terrain road. You also can buy this hub on local bike shop with low cost.
2. 142mm x 12mm Axle Hub
This hub used to be the standard before year 2017. The dimension of hub length and diameter are changed as 142mm and 12mm. The space between the right and left spokes head is not changed.
To use this hub type, the frame must have the suitable size to fit the hub length and suitable hole diameter to fit the axle. The frame wide is increase to 142mm, give the capable to assemble the larger tire.
3. Boost
Same to front Boost, rear Boost is become the new standard, replacing the 142mm hub. Each side pluses 3mm, increase the space between the right and left spokes head up to 6mm. The declination of spokes is increased, so the wheel is steadier. The frame also widens to 148mm, be able to applied the bigger tire compare to 142mm one.
If you want to upgrade you bike to used Boost, you have to change almost all such as frame and components that can apply Boost for maximum effectiveness. That means you have to spend a lot of cost. Besides, Boost hub and related component is hardly find in Vietnam market. However, the quality of these stuff is awesome.
Which hub is fit with your bike?
1. Measure the frame size
If you use QR Hub, you don’t have to measure.
In case you use others or Boost, let measure the space of frame where the hub is standing. So, you can know which hubs are fit with that length.
After making sure the size of hub, you have to check what kind of disk you want to use. There are 2 kinds of disk: Six-bolt and Centre lock.
+ Six-bolt disk is attached on hubs with six standard evenly-spaced holes to bolt on a matching rotor
+ The Centre lock disk is attached on splined hub-rotor interface secured with a locking ring
Each model of hub just has 1 way to attach the disk. Base on your disk type, choose the suitable one.
There are 2 types of cassette driver body:
+ Standard Diver Body (Shimano as standard): use 8,9,10 or 11-speed cassette of Shimano
+ XD Driver Body (Sram as standard): use 11-speed cassette of Sram and 12-speed cassette
Each model of hub just has 1 type of driver body. Base on your cassette, choose the suitable one.