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Questions and answers about sports

Why are hub shells such different diameters?

6 min read

Asked by: Jose Capers

Are all bike hubs the same size?

Hubs have to be matched to the front or rear of your bike; each will be a different size.

What are the different hub sizes?

Common Sizes

  • 100mm – Modern front hubs, including quick release and some thru axle types.
  • 110mm – Some thru axle front hubs including 20mm and boost standards.
  • 110mm rear – B.M.X.
  • 120mm rear – Modern Track hubs.
  • 126mm rear – Older 5 and 6 speed road bikes.
  • 130mm rear – non-disc road bikes.

What are the different types of bike hubs?

There are four types of hubs available: the track hub, the flip flop hub, the freewheel hub or the cassette hub. The recommended way to go for a fixed gear setup is to construct a new rear wheel. You can use a track hub in such an activity. The distinct feature of any track hub is their stepped threads.

What hubs do pro cyclists use?

The distinctive green hubs are Chris King R45s. They use lightweight hub bodies and bearings that are made in-house. The rear hub features a RingDrive system with 45 teeth for fast engagement.

How do I know my hub size?

Measure across the middle of the wheel hub to get the diameter. The wheel hub bolt pattern is the number of bolts lugs on the hub and the diameter of the circle in which they are arranged.

Which is better Pawls or ratchet?

Ratchet systems are generally spoken stronger, more reliable and need less maintenance compared to traditional pawl systems. Biggest reason for this is that the power transferred from the drivetrain to the wheel is spread of a larger surface. In general hubs that are “louder” usually have more engagement points.

Do hubs make your bike faster?

2- They are Faster



Because loud hubs have more engagement points and pawls, they engage faster which makes pedaling quick. The fast engagement that occurs when you start pedaling results in less energy being lost through your pedals.

What does hub size mean?

The outer diameter is the hub bore, while the inner diameter is the diameter of the vehicle hub itself. For example: a hub-centric ring size of 73-67.1 would mean that the wheel center bore is 73 mm wide and the vehicle hub is 67.1 mm wide.

What is the difference between HG and XD hubs?

Micro Spline uses 23 splines to mount the cassette, whereas HG has only 13. This extra spreading of load makes aluminium freehub bodies more durable. XDR vs XD is just the same as Shimano’s 11-speed HG road vs MTB. Probably the Micro Spline road system will have the same thing, but it hasn’t been released yet.

Do all cassettes fit all hubs?

Most cassette hubs are compatible with Shimano cassette cogs. SRAM cassettes and most Miche, IRD and SunRace cassettes use the same inter-sprocket spacing as Shimano, but at least some SRAM 10-speed cassettes do not fit aluminum-body Dura-Ace hubs.

How do I choose the right hub?


Quote from video: And in turn the size of hub you will need hub sizes are determined by the size and shape of the spindles on your trailers. Axle. After removing the wheel an existing hub look at the spindle.

Are bike hubs worth upgrading?

The quality of your hubs has a significant effect on the weight, rotational resistance and rigidity of your wheels. An upgrade hub is likely to have better bearings, that could potentially be cartridge bearings; these are likely to last longer and be more easily replaced when they have had their day.

Do hub centric rings have to be exact?

Quote from video: And it's suggested. That you use them again they're not structural safety pieces. But this is what makes sure that the wheel is perfectly centered on the hub.

Does wheel hub size matter?

Hub diameter is, therefore, an extremely important consideration when fitting new wheels, whether OEM or aftermarket. If the hub diameter is smaller than the axle, the wheel will simply not fit. Most aftermarket wheels are, therefore, made with larger hub diameters to ensure that they will fit on a wide range of cars.

How tight should hub centric rings be?

The most important thing is the tightness of the fit of the wheel on the hub. Whichever one gives a tight fit that doesn’t allow any movement of the wheel. My hubcentric rings fit very snug to the wheels, but are a close/accurate fit to the hubs.

Can you change the hub on a bike wheel?

Simple answer: yes, but it’s not worth doing. Cost of hub, spokes, nipples and having wheel rebuilt will exceed the cost of a new wheel. Even if you re-use the spokes a new wheel will still be cheaper. Wheel building requires special equipment, expertise and time to do correctly.

How do I choose a bike hub?

– there are a number of things to take into acccount when choosing a new hub or hubset, among them bearing type, materials, disc mount standard, axle type and rims. Bearing type: Good-quality bearings, sealed and protected from dirt and water, are the key to long and healthy hubs.

What is the difference between HG and XD hubs?

Micro Spline uses 23 splines to mount the cassette, whereas HG has only 13. This extra spreading of load makes aluminium freehub bodies more durable. XDR vs XD is just the same as Shimano’s 11-speed HG road vs MTB. Probably the Micro Spline road system will have the same thing, but it hasn’t been released yet.

Are all quick release skewers the same size?

Typical sizes for front and rear bolt-thru axles are 10mm, 12mm, 15mm and 20mm depending on riding discipline and manufacturer’s standard, so ensure you purchase the correct size to fit your forks and hubs (in the case of the latter, adapters are available to enable hubs be used with regular 5mm QR, or different-sized

How are quick release hubs measured?

Measuring a quick-release assembly for replacement



Diameter: the skewer must fit inside the hollow hub axle. You may measure either the inside diameter of the axle, or the diameter of the present skewer. Most axles use a 5mm thick skewer.

Are quick release skewers standard size?

A quick release wheel has a hollow axle, 9mm in diameter at the front and 10mm at the rear, with a 5mm diameter skewer that passes through it. Until recently, all road bikes used rim brakes and they all had front axles that were 100mm wide and rear axles that were 130mm wide.