As of 2018, fatbikes and disk brakes have led to a several new standards. The problem of disk brakes' pulling the hub out of the front dropouts (see James Annan's article) has been addressed with through axles, which insert into a fork with a hole rather than a slot at the end of each blade. Also see our article about disc brakes for information on disc-brake issues.
| 70 mm | Birdy, Breezer Itzy front hub. |
| 74 mm | Brompton front hub, 8 mm axle; Schimidt SON XS Bro generator hub. |
| Bike Friday tikit, Dahon Speed, Moulton front hub, 9 mm axle; Schmidt SON XS DaTi generator hub | |
| 79 mm | Dahon Vitesse front hub (report from reader, unconfirmed). |
| 91 mm | Low-end front hubs. |
| 96 mm | Older front hubs, especially French. |
| 100 mm | Modern front hubs. |
| 110 mm | Rear older track, coaster brake and other single-speed hubs. Also, front hubs for Downhill bikes with 20 mm axles. |
| 114 mm | Rear 3-4-speed. This is US, U.K. Same as 4 1/2 inches. |
| 120 mm | Rear 5-speed, Ultra 6, newer track hubs. |
| 126 mm | Rear 6- and 7-speed (road). |
| 130 mm | Rear 7-speed (MTB) and 8- 9- and 10-speed (road). |
| 135 mm | Rear 7- 8- and 9-speed (MTB) |
| 140 mm | Rear tandem. |
| 145 mm | Rear tandem (newer models.) |
| 150 mm | Retro-Choppers, some Downhill and Freeride models. |
| 160 mm | Rear tandem (new Santana proposed standard.) |
Overall axle length for quick-release hubs is commonly 11 mm longer than the overlocknut distance listed, 5.5 mm on each side. Most hubs with nutted axles can easily be modified for larger spacing by adding washers, within limits. For overlocknut distance of specific makes and models of internal-gear and singlespeed hubs, see the articles on chainline.
| Brand and model | Center-to-center Spacing |
Sprocket Thickness | Spacer Thickness | Total Width |
|---|---|---|---|---|
| 5-speed | ||||
| "Regular" 5-speed |
5.5 mm | 2.0 mm | 3.5 mm | 24.0 mm |
| G. Caimi/Everest/Simplex 5-speed |
5.35 mm | 1.85 mm | 3.5 mm | 23.2 mm |
| 6-speed | ||||
| "Regular" 6-speed |
5.5 mm | 2.0 mm | 3.5 mm | 29.5 mm |
| G. Caimi/Everest/Simplex 6-speed |
5.35 mm | 1.85 mm | 3.5 mm | 28.6 mm |
| Sun Tour "Ultra" Freewheel 6-speed |
5.0 mm | 1.85 mm | 3.15 mm | 26.9 mm |
| Sun Tour Accushift XCD-6 6-speed |
5.5 mm | 2.0 mm | 3.5 mm | 29.5 mm |
| 7-speed | ||||
| Shimano HG 7-speed |
5.0 mm | 1.85 mm | 3.15 mm | 31.9 mm |
| Shimano IG 7-speed |
5.0 mm | 2.35 mm | 2.65 mm | 32.4 mm |
| Sachs 7-speed |
5.0 mm | 1.8 mm | 3.2 mm | 31.8 mm |
| SRAM Freewheel 7-speed |
5.0 mm | 1.8 mm | 3.2 mm | 32.8 mm |
| Sun Tour "Ultra" Freewheel 7-speed |
5.0 mm | 1.85 mm | 3.15 mm | 32.4 mm |
| Sun Tour MicroDrive 7-speed |
4.8/5.0 mm | 2.0 mm | 3 x 2.8 mm(L) 3 x 3.0 mm(H) |
31.5 mm |
| 8-speed | ||||
| Campagnolo 8-speed |
5.0 mm | 1.9 mm | 3.1 mm | 36.9 mm |
| Mavic 8-spd w/rounded dogs |
5.2 mm | 2.0 mm | 3.2 mm | 37.0 mm |
| Shimano 8-speed |
4.8 mm | 1.8 mm | 3.0 mm | 35.4 mm |
| Sachs 1997 8-speed |
5.0 mm | 1.8 mm | 3.2 mm | 36.8 mm |
| Sachs 1998+ 8-speed |
4.8 mm | 1.8 mm | 3.0 mm | 35.4 mm |
| SRAM Cassette 8-speed |
4.8 mm | 1.8 mm | 3.0 mm | 35.4 mm |
| SRAM Freewheel 8-speed |
5.0 mm | 1.8 mm | 3.2 mm | 36.8 mm |
| Sun Tour MicroDrive 8-speed |
4.8/5.0 mm | 2.0 mm | 3 x 2.8 mm(L) 4 x 3.0 mm(H) |
36.5 mm |
| 9-speed | ||||
| Campagnolo 9-speed |
4.55 mm | 1.75 mm | 2.8 mm | 38.2 mm |
| Shimano 9-speed |
4.34 mm | 1.78 mm | 2.56 mm | 36.5 mm |
| SRAM 9-speed |
4.34 mm | 1.8 mm | 2.54 mm | 36.5 mm |
| 10-speed | ||||
| Campagnolo 10-speed |
Variable (note) | 1.7 mm | Variable (note) | 38.8 mm |
| Shimano 10-speed |
3.95 mm | 1.6 mm | 2.35 mm | 37.2 mm (note) |
| Campagnolo 11-speed |
Variable (note) | 1.6 mm | Variable (note) | 40.1 mm (note) |
The total width given is that of the sprocket cluster. A freewheel with splined sprockets has a flange behind the innermsot sprocket. The inner body of the freewheel may not be recessed so as to compensate completely for this flange depth, and so the total width the of the freewheel may be greater, affecting chainline and clearance at the right rear dropout. Sun Tour freewheels typically have a 2 mm flange and a 1 mm recess.
The innermost sprocket of Shimano 10-speed and Campagnolo 11-speed cassettes is inboard of the flange of the freehub body to move the sprockets to the left and make more room between the outermost sprocket and the dropout. The rear derailer may interfere with the spokes, especially if the innermost sprocket is relatively small or the wheel has an unusual spoke pattern.
Sprocket spacing varies across Campagnolo 10- and 11-speed cassettes to improve shifting in the midrange. 11-speed spacing also varies over the top 3 sprockets according to the actual ratios for better shifting with the most recent 11-speed rear derailleur. Thanks to Graeme at Velotech Cycling Ltd. (UK) for this information.
Last Updated: by Harriet Fell
