Small Wheels Good

Amongst the more performance-oriented parts of the cycling community, there is something of an aversion to small wheels. Large wheels have certain benefits, they deal with uneven surfaces better than small wheels and the wheel does fewer revolutions for a given distance, leading to longer tyre life.
There is a common misconception that larger wheels are faster. At very high speeds, there are benefits to larger wheels due to the gyroscopic effect, but these only come into effect at speeds seldom sustained for long by even professional cyclists. At low speeds, the reduced weight and air resistance of a smaller wheel makes them faster than their larger counterparts, making them ideal for transportation use in start-stop traffic.

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An original Moulton bicycle from the 1960s, spotted in Chorlton.

The 200 m flying start world speed record for a bike using the conventional riding position was set on a modern Moulton in 1985.
Another advantage of a smaller wheel is strength. Shorter spokes make for a stronger wheel, just look at the amount of punishment the 20 inch wheels used by BMXers are put through. The strength of smaller wheels is also put to clever use in the Madsen bicycle and the Bakfiets (images taken from respective sites):

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Madsen bucket bike

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Workcycles bakfiets

Smaller wheels make hub-based brakes more effective. Drums, rollers and discs all work better on smaller sized wheels due to their central location. I use a drum brake on my Raleigh Twenty and it is more powerful than the same unit on my DL-1.
As has been discussed over at Lovely Bicycle! smaller wheels increase the range of rider sizes which can be accommodated. Sadly, the desire on the manufacturers’ part to only use one wheel size for a given model means that proportionally smaller wheels are seldom used for smaller sized frames (such as 650Bs on a smaller touring bike rather than 700Cs). Added to this is the common misconception that smaller wheels are slower, meaning that small wheeled bikes for touring are still a niche market (The Moulton being the only small-wheeled dedicated touring bike which springs to mind).

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The Raleigh Twenty was Raleigh’s more-affordable answer to the original Moulton. Raleigh eventually owned Moulton for a time.


Small wheels are also more manoeuvrable, which is a desirable trait when riding in traffic, as many Bromptonauts will agree. Finally, small wheels are easier to store. This is not just useful for folding bikes like the aforementioned Brompton, but also for rigid bikes such as the Moulton and the Twenty. The Twenty doesn’t get the same special treatment on the train as a folder, but it is much easier to take in and out of a train, or to squeeze into a gap somewhere during busy periods. It is also easy to take into a house rather than lock up outside, and the small wheels make the whole package easy to carry up a flight of stairs.

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Type M Brompton. Brompton, like Pashley and Moulton are one of the few companies to still make their bikes in the UK

Small and large wheels each have their own advantages, when choosing a bike, don’t count small wheels out too quickly.
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11 thoughts on “Small Wheels Good

  1. It's unfortunate that the choices in wheels sizes have been restricted. A lot of parts seem to be still available though if you hunt around, and hopefully with renewed interest may once again become commonplace.The link to Moultons site is interesting – UCI (Union Cycliste Internationale) rule 1.3.018 – in that another threateningly different machine, the Recumbent was ruled out ofthe equation in 1934 for the same reasons ;>)

  2. Your link to Moultons site is interesting – re the UCI rule – because the same thing happened to another threateningly different machine in 1934, when the Recumbent was banned from competition ;>)Hopefully as practical bikes become more popular, more choice will become available again – rims & tyres are still available in a lot of odd sizes so y'never know.

  3. Almost all of the odd sizes can still be bought from specialist shops like SJS, but there are very few complete adult bikes sold with wheels other than 700C or 26 inch. It seems a shame that a smaller rider would have to pay a massive premium to buy from a significantly smaller range of bicycles designed to have proportionally smaller wheels such as 650Bs. I can see how the expense stops the manufacturers wanting to offer these models as standard though.The recumbents can reach silly speeds if enclosed in an aerodynamic shell (think in the flux capacitor kind of area). The UCI does seem to stifle progress in that area a bit. It is probably a good thing in the real world though, considering how much of an influence sport cycling has on transportation cycling in the UK. I can imagine that if aero-recumbent racing was allowed we would be seeing people splashing out on them to totally "Own" their commute.

  4. Small wheel bikes can be just as "fast" but they require a larger gear ratio to do so. Therefore, when you encounter a hill its more difficult to overcome the gear ratio you're dealing with. There are some folding bikes out there that do use full size wheels. Check out Montague Bikes. They make bikes with 26" or 700c wheels that still fold for easy transport or storage. Also, they don't put any cuts or hinges in the frames so they're rock solid. Pretty unique design if you ask me! Check them out at http://www.montaguebikes.com

  5. The 650Cs on the Wimmins Pashleys are a nice size – with the standard Schwalbes they have the radius of a 700×23 but with the comfort of the thicker tyre profile.Soz, a bit off topic there!

  6. I do love my Brompton, but the "wheel strength" argument is a bit chimeric – a well built wheel will put up with what you throw at it, by and large. I have 16" wheels on the Brompton (along with Brompton's godawful rim tape, which makes getting the tyres off a chore) and 700c 36 spoke 3x on my tourer.The tourer's wheels have survived laden touring on Belgian cobbles, as the Brompton's wheels have survived daily commuting on the less than ideally surfaced roads of Crewe and Manchester. Unless you're hauling serious weight (Yuba type weight, I'd say) build quality (and what you like riding) is more significant than rim size.Oh, and Raleigh Twentys are terrible bikes, honest they are. You don't want one. (Hopefully that'll stop them becoming cult items before I can pick one up myself 😉 )

  7. "Small wheel bikes can be just as "fast" but they require a larger gear ratio to do so. Therefore, when you encounter a hill its more difficult to overcome the gear ratio you're dealing with."The Brompton S6 I have seems to manage quite well – 1st gear is far lower than I've ever needed, even heading up the service road out of the old UMIST campus. Similarly, I've yet to spin out in 6th gear, it's pretty high. Most riding is done in 4th or 5th, and 3rd is plenty low enough for pulling away from lights.With folding bikes, I think the choice can be characterised as being between a bike that folds, or a folding bike. The Brompton is in the latter camp – there are some compromises, but the fold is unbeatable, intuitive, quick and impressively compact. The Montague (and larger wheeled Dahons, like the Jack and Cadenza) are more like "proper" bikes, but you'll not squeeze them into the spaces a Bromtpon can fit into.

  8. @RyanThe smaller wheels do effectively lower the gearing and make the gaps between gears smaller. This can be beneficial for certain applications, and can be worked around using things like the wide-ratio 3-speed hub in the Brompton. Most of the derailleur geared small-wheelers I have ridden have had a fairly poor gear range, mainly because they used 14-28 freewheels rather than something like a 11-34 cassette.@ian,The smaller womens' Pashley is a rare exception to the wheel size thing (Pashley as a whole is a bit of an exception). It is great that they offer a smaller wheel size on the smaller model rather than forcing 700Bs on small riders.@John,You can simply build a stronger large wheel, but the production costs and (for the performance-oriented only) weight go up. The Brompton front wheel for example is radially spoked with a 28 hole rim. I can't imagine a similarly made 700C wheel dealing with daily use quite as well. However, for most people wheel strength isn't really much of an issue. Overbuilding the wheels isn't a problem on cargo bikes where the weight of the bike is less of a consideration for most buyers, the Yuba Mundo's 48 spoke rear wheel being an example of this as you said.As for the Twenty, if you search for "Shopper" bikes rather than Twentys, you tend to get better prices. People who know their bike is a Twenty already want more money for them, due to the Sheldon Brown effect (and the fact that they are great little bikes).

  9. "You can simply build a stronger large wheel, but the production costs and (for the performance-oriented only) weight go up. The Brompton front wheel for example is radially spoked with a 28 hole rim. I can't imagine a similarly made 700C wheel dealing with daily use quite as well. However, for most people wheel strength isn't really much of an issue."I'd not spoke radially for preference (3x is just fine), although my first bike had a radially spoked front (28 spoke) and it was grand – true until replacement following a collision with a car. The replacements (similar, but 3x all round have been faultless, even with fairly modest components (Tiagra hubs, DRC rims) and less cushy high pressure tyres (generally 25c at 95psi). Ironically, you have to spend real money to get a 700c wheel that would be troubled by commuting use, so much so, that you'll not see folk commuting on them, even roadies. Of course, all the above assumes a properly built wheel (even-ish spoke tension, &c)The Brompton wheel is radial because of limited space, as I recall, and the need to keep the angle at the rim sensible. You can't spoke radially at the rear, so they go for 2x as a least worst option. As rim size increases, "better" options (like 3x) become available. Some hub dynamo and hub gear wheels are built 2x for similar reasons (although in these cases it's the larger hub reducing the space available).There is an "if everything is equal then" argument that smaller wheels are stronger than larger, but I'd argue (as you acknowledge) that few of us are ever going to reach the point where that's something to worry about. Touring fora are full of that kind of thing (26" vs 700c) (along with the need to use bar-end shifters, because you can't get replacement STi levers in Africa – never mind that most of the participants won't be leaving mainland Europe!)I think your space argument is a more compelling one, personally – it's one of the reasons mini velo are so popular in Japan, I believe, less space for storage.Thanks for the tips on twentys – I still regret not grabbing one I saw left out for the bin men a couple of years ago!

  10. I just noticed how poorly locked the Moulton was, especially considering the fact that the originals can be worth a small fortune.@JohnI agree absolutely that under normal usage, the strength benefit is a bit of a non-issue really (although beneficial on cargo bikes etc). The space argument is a good one, after all cities are ideal places for bicycles, and how many of us city-dwellers live in flats with no or minimal provision for bike storage. Even the tiniest flat could accommodate a Twenty, Brompton or (if filthy-rich) a Moulton.I just spotted this on eBay, not technically a Twenty, but almost exactly the same (I think the brace near the fork was added to avoid legal action from Raleigh).

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