Search sheldonbrown.com and sheldonbrown.org
The Raleigh bicycle company is one of the oldest in existence, going back to the early years of the 20th century. Back then, screw threads and other dimensions were not standardized to the same extent that they are now. Each manufacturer would develop its own proprietary "standards."
Over time, this caused so much confusion and difficulty that it led to a gradual movement toward industry-wide (or at least nationwide) standardization. In Great Britain, most of the builders wound up standardizing on the dimensions used by B.S.A. (Birmingham Small Arms), an important bicycle and firearms maker in the early 20th century. Indeed, the B.S.A. standards became adopted as the "B.S.C." (British Standard Cycle) dimensions, and ultimately formed the heart of the ISO international standard in use today.
At the time of this transition, Raleigh was the Microsoft of the bicycle industry, and did not choose to go along with the adoption of B.S.A./B.S.C. standards. Right through the 1990s, the bikes built at the mighty Nottingham Factory were made to Raleigh proprietary dimensions. Since Raleigh made virtually every part of these bikes, there was no compelling need to match standards used by other manufacturers. (We shouldn't be too hard on Raleigh about this. Making the change would have been very, very costly, and wouldn't have benefited the shareholders in any way.)
The main difference is that most B.S.C./ISO screw threads have a pitch of 24 threads per inch (TPI), while the corresponding Raleigh parts have a slightly finer 26 TPI threading.
The easiest way to identify Raleigh-built bikes is by looking at the rear dropouts. Almost all Raleigh-threaded bikes have the rear fender eyelets located directly behind the axle, instead of above it. (This doesn't apply to roadsters, which don't generally have dropouts or fender eyelets.)
Most Raleighs use a seatpost diameter of 1" (25.4 mm) while other British 3-speed bikes usually use 1 1/16" (27.0 mm)
Some sporty models have more conventional dropouts, but you can identify these by the distinctive Raleigh headset and bottom bracket cups.
The width of the bottom bracket shell is also an indication. Standard British (24 tpi) bottom bracket shells are 68 mm wide, give or take a mm. Raleigh 26 tpi shells are generally 71 mm or 76 mm wide.
In later years, higher-end Raleigh models such as the International, Professional, Competition, Grand Sport and other models built at the separate Carlton workshop used B.S.C. threading, as did models made in Asia and the United States. These bicycles all used cotterless cranks.
Generally speaking, Raleighs that use cottered cranks also have Raleigh 26 TPI threading for both the bottom bracket and the headset. These include all Nottingham-built bicycles sold with a coaster brake or internal-gear hub, as well as lower-priced derailer-equipped models up through the Super Course, which had a frame of plain-gauge Reynolds 531 tubing. Although the diameters are the same as B.S.C., the different thread pitch makes the parts incompatible. This article will provide strategies for getting around this problem.
With an older bike, there is often a question of whether to preserve it for posterity in "original" condition or to upgrade it for use. The answer to this question generally depends on rarity, age and condition.
Nottingham Raleighs were built in huge numbers, and they were so well-made that quite a lot of them have survived, so most of them don't really qualify as "rare."
Very few English bikes were imported to the U.S. before World War II, so it is unusual to see really old ones. That said, I'd generally consider anything from the 1960s onward to be fair game, with 50s bikes on the borderline. (I have a separate page about dating your Raleigh bike.)
To be a good candidate for restoration, a bike should already be basically complete, and free from rust.
Note that these issues are a moving target, and will change over time as these bikes become increasingly rare. I think of my father, who grew up tinkering with Model T Fords. When he was a young man, old Model Ts were basically throwaway cars, cheap and plentiful. Hot-rodding or otherwise modifying them was a popular avocation, and perfectly reasonable at the time...even though, now, a complete, original Model T is worth big bucks.

Raleigh bottom-bracket cups have raised ridges on their surfaces, which fit a 5/8" or 16 mm open end wrench. The best tool for them is the Park HCW-11 (TL7063). For information on servicing the stock cottered setups, see my articles on:
By far the cheapest option is to keep the original 26 tpi Raleigh cups, and install a new spindle with the tapered square ends needed to fit cotterless cranks. Not all spindles will fit, unfortunately. Some of them are just a bit too thick to fit the slightly smaller inside diameter of the Raleigh cups, even though they all are made for 11 1/4" balls on each side. Sometimes you can make the thicker spindles work by using slightly smaller 15/64" or 6 mm balls. Japanese spindles will usually fit with the standard 1/4" size.
Raleigh cups are no longer made, but they are extremely hard. Used cups in good condition may often be salvaged from a trashed frame.
Raleigh bottom bracket shells are wider than the standard 68 mm width of B.S.C./ISO bottom brackets, commonly anywhere from 71 mm to 76 mm. As a result, you'll need a longer-than-normal spindle. Japanese spindles are generally designated by a simple code consisting of a single digit followed by one or more letters.
Just getting a spindle to fit into the frame is a start, but you may still have problems due to the overall length of the spindle. Older cranks used longer spindles than newer, "low profile" cranks. Axles of the type described are mostly available in longer overall lengths, which are likely to give poor chainline with newer cranks, though they will work. If you are spreading the rear dropouts of a frame to use a wider hub, you may want to increase the chainline anyway.
See my article on Bottom Bracket Sizes for information on spindle lengths for different cranks.
Modern cartridge bottom brackets are much easier to deal with than the old-style cup-and-cone design. There are three possibilities for running a cartridge bottom bracket in a Raleigh 26 TPI shell:
Phil Wood bottom brackets are sold separately from the mounting rings that screw into the frame. Phil Wood is the only manufacturer still supporting 26 TPI bottom bracket threading. The quality is superb, there's nothing better. Phil Wood bottom brackets are available in a great variety of spindle lengths, too. The bad news is that Phil Wood bottom brackets are among the very most expensive available.
Phil Wood retaining rings don't have any shoulders, so they can be screwed all the way into the shell, even recessed below the edge of the shell. This greatly reduces problems due to the wider shell width, and allows chainline adjustment by several mm.
Phil Wood bottom-bracket cartridges are available in two widths, nominally for 68 mm and 73 mm bottom bracket shells. The 68 mm version will work with a 71 mm Raleigh bottom bracket. The 73 mm version must be used with a 76 mm bottom-bracket shell, or else there is a risk that the mounting rings will run up onto the end of the threads inside the bottom-bracket shell and bind.
It happens that Shimano UN72 bottom brackets can also be used with Phil Wood retaining rings. The UN72 model is the only Shimano series you can use this way, because the other Shimano models have the right side threads machined into the cartridge body. The UN72 is even narrower than the Phil Wood 68 mm cartridge, and so it is only usable with a 68 mm bottom-bracket shell.
Unfortunately, for the 2003 model year, Shimano replaced the UN72 bottom bracket with the revised UN73 design. The UN73 is a fine bottom bracket, but it does not have a removable mounting ring on the right side. The threads are part of the shell, as with the other Shimano cartridges, so the UN73 will not work with Phil Wood rings.
Velo Orange makes a bottom bracket that clamps into the bottom-bracket shell with internal-expanding sleeves. It is described in an article on this site.
This option is the most versatile, but also the most drastic. Only the top bike shops will have the necessary guided tap set required for this. The threads will not be as strong as they would be if the shell was made for standard threading, but this approach generally works well. You will still need to deal with the overall shell width. A shop that has the correct taps will also have the correct tool to face the ends of the shell, and this tool can be used to bring the width down to a more standard size (though it takes a lot of elbow grease! Beware, though, the welds to the bottom bracket shell of a Raleigh Twenty can be very hard, maybe harder than the taps.

You can even mix and match. If your Raleigh headset cups are worn out or rusted on the load-bearing bottom section, you can replace just the bottom with any standard ISO 1" headset parts, and re-use the Raleigh upper assembly.
The forks used on most Nottingham Raleighs have keyhole-shaped axle slots. These are designed to fit Raleigh hubs, with thin (5/16") solid axles and wheel retention shoulders on the cones. The spacing between the inner faces of the fork ends is less than the modern 100 mm standard. If you wish to mount a modern hub on a Nottingham Raleigh, be prepared to do some filing on the fork ends, to enlarge the lower part of the slots to fit the modern axle. Use a good sharp file, and, if possible, have the fork end itself clamped into a sturdy vise. If you don't, vibration of the fork will make it difficult to file. Make sure you file both sides the same amount, so the axle will not go in crooked.
The fork blades should be spread to match the over-locknut dimension of the hub. The dropouts will need to be realigned as well, to avoid bending the hub axle after the blades have been spread. The fork rake of Raleigh three-speeds is rather large, and so trail is less than optimal, and unbending the fork blades a bit can improve handling. I hesitate to advise realigning a fork unless you have access to a proper jig. You could just replace the fork instead.
Most Nottingham Raleigh rear dropouts have narrow (8 mm) slots intended for the flat-sided axles common on Sturmey-Archer and other older British hubs. Most modern rear hubs are 10 mm, some are even 10.5 mm, so you will need to file the rear as well. I recommend doing all of the filing on the bottom of the slot. This eliminates the risk of making one side higher than the other.
Dropout spacing on bikes made for 3-speed applications is typically 114 mm (4 1/2 inches). 5-speed derailer systems usually used 120 mm. Many upgrades will call for a wider dropout spacing.
See: my article on Frame Spreading for instructions on this.
The typical Raleigh-built 3-speed comes with 590 mm (26 x 1 3/8) rims, with long-reach brakes, around 75 mm at the front and 80 mm at the rear.
If you switch to 622 mm (700c) wheels, you'll need brakes with a reach of about 60 mm at the front and 65 mm at the rear (but measure -- this may vary). 700C wheels are a recommended upgrade, both for the greater variety of available rims and tires, and for better braking. Modern dual-pivot sidepull brakes with the required reach, such as the Tektro R556, will work. The larger wheels will raise the frame by 10-18 mm depending on the width of the new tires, an issue if the frame already borders on being too large.
700C wheels risk interference with the original steel fenders, but modern, adjustable plastic fenders will work fine. They also are much lighter.
If you switch to 559 mm (26" MTB size) you'll need very long-reach brakes. Such brakes are often a bit anemic due to the long arms; also, the bottom bracket will be low, reducing cornering clearance.
If you wish to use 559 mm wheels, it is often a good idea to replace the fork with a MTB fork with cantilever bosses. You then have the option of raising the front end of the bicycle, and with it the bottom bracket too, especially if you use a suspension fork. If you're handy, you can even braze cantilever mounts onto the rear. See my article on installing cantilever braze-ons. Or, you may use a home-made drop bolt.
The Raleigh Twenty has special brake-reach issues, as it was sold with either of two different wheel sizes.
As mentioned above, Raleigh forks are completely standard except for the thread pitch. Thus, any standard stem with a 7/8" (22.2 mm) quill will fit into the forks.
There is an issue, however, at the top end of the stem. This is not a Raleigh-specific issue, but applies to older British bikes from all makers. The handlebar clamp diameters on older British bicycles depended on the material of the handlebars, rather than what type of bars they were. Specifically, steel handlebars (and the stems made for them) used a 15/16" (23.8 mm) clamping diameter at the middle of the bar. Most Nottingham Raleighs have this type of bar/stem.
Thus, if you wish to replace the stem and keep the handlebar, the hole in the new stem will be too large to clamp properly. You can get around this by using a shim to make up the difference, though this is a bit inelegant.
If you want to replace the handlebar, you should really replace the stem too, because it is unsafe to overspread the 15/16" stem to fit a standard 1" (25.4 mm) handlebar.
The eyelets in the fork ends, where the fender/mudguard stays attach to the frame, also use a non-standard, Raleigh-specific threading. It is common to tap these out to the standard 5 x .8 metric size.
The location of the eyelets at the back of the rear dropouts calls for shorter fender stays than normal at the back of the fender, and longer at the top of the fender. This is not a problem with most newer fenders because they have adjustable stays.
The eyelet position can also be an issue with some rear luggage racks, because the legs may not be long enough to let the rack clear the top of the fender. Racks designated as being for "hybrid" bikes will usually work.
![]()