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Single-speed Cycling

Until 1937, when they were first permitted to use derailleur gears, those giants of men who competed in the Tour de France – and in all other races up to a similar year – rode bikes with just a single gear. Initially, in the case of the Tour until about 1906, they were not permitted to use freewheels, thus rode fixed-gear or fixed-wheel. Whenever the rear wheel was rotating, so the pedals were rotating too. The advent of the freewheel at least allowed the rider some respite from constant pedalling, and helped average speeds increase. However many races were won at very respectable speeds despite the absence of derailleur gears: most riders mounted sprockets of different size on each side of the rear wheel, and could thus change gear by removing the wheel and flipping it over to use the other gear. Later some put double sprockets on one or both sides, and changed gear by manually shifting the chain from one to another. This often required a chain tensioning device, which can be seen in some contemporary photographs.

There are plenty of good reasons for still riding single-speed bikes even today. They are much simpler, cheaper, and can easily be as light as much more expensive geared bikes. Moreover they are excellent for training, as you have a simple choice: pedal in the single gear, or walk! You cannot progressively chicken out on a hill and crawl your way down to 'granny' gear. When travelling at higher speeds, you must learn to pedal smoothly at very high cadences of 120 per minute or more, and this builds what is termed souplesse in your pedalling style. Traditional European training methods for pro cyclists normally put them back on a fixed-wheel or single-speed bike when they returned to training in the New Year, and used that to improve souplesse before switching back to a normal road bike after 1000 to 2000 miles. Being so simple, single-speed bikes are ideal for bad weather training, as they can be cleaned and maintained very quickly. Some pros still recommend single-speed or fixed-wheel bikes for certain types of event, notably hill-climbs, although no-one would attempt more general or multi-stage road racing on such a machine now.

Riding single-speed and fixed-wheel can normally be done on the same bike, but they are quite different experiences. Fixed-wheel has been described as an almost spiritual experience, in which you forge an intimate link with your bike, the ultimately pure bike ride. However it can be dangerous: 'fixies' tend to dispense with brakes, as you can brake your rear wheel by slowing the pedals down. In traffic and many real road situations, this can prove risky. When riding fixed-wheel, your pedals are constantly rotating, so you cannot position them to avoid groundstrike when cornering. Finally, if you ride fixed on hilly routes, descents can force extremely high cadences, and the slightest mistake such as a desire to freewheel can be catastrophic. If you want a similar experience but without the spiritual depth and concomitant risks, ride single-speed rather than fixed-wheel.

I currently have two single-speed bikes, both of which have flip-flop rear wheels that allow them to be ridden as fixed-wheel machines. They illustrate some of the joys of riding fixed.

Giant Bowery (plus)

The first is based on a Giant Bowery, for which I paid just £350. The Bowery is intended as a messenger bike, and despite its aluminium version of the Giant Compact Road frame (shared with my carbon fibre TCR C2), has much higher aspirations. The photos illustrate how it stands today, with replaced brakes, wheels, and saddle.

Giant Bowery

Bowery close-up

Bowery close-up

Bowery close-up

Bowery rear hub

Giant Bowery (2008), modified with Shimano Ultegra brakes, MK wheels, and Continental GP 4 Season tyres.

This is just the start: these wheels are not bad for training, but could be much better, and will be replaced again shortly. One of the snags with riding single-speed is that few factory-built rear wheels will prove suitable. Good single-speed frames have proper track dropouts at the rear, with the rear-facing slot that makes it easy to tension your chain correctly. However, the distance between those drop-outs is normally 120 mm, instead of 135 mm in standard road frames. So you need a track hub (which can be bought with threading for a freewheel on one side, and a fixed gear on the other) on the rear. But you cannot use a track wheel there, as your rear brakes need a standard road rim, with a suitable braking surface. These factory-built MK wheels meet the need, but I am getting a better rear wheel built on a Phil Wood hub.

Transmission components are mostly derived from track components, and in the next couple of week this Bowery should benefit from a Shimano Dura-Ace Track chainset and bottom bracket, plus a higher quality freewheel and 1/8th inch chain. The numbers are 46 x 17T transmission giving a nominal 71.9 inch gearing to 700 x 25C tyres.

Kona Paddy Wagon

I also splashed out another £100 more on a Kona Paddy Wagon, a much smoother and polished single-speed road bike that is built on a lovely Cr-Mo steel frame. The extra cost allows higher-quality components all round, and my current plans are to replace the tyres with something suitable for tracks and light off-road use as well as tarmac. The Paddy Wagon is super-smooth on the Island's rough and ill-maintained roads, and despite being significantly heavier than the Giant Bowery (particularly with its weight-loss programme), it remains very quick and a pleasure to ride. Kona has also opted for an easier gearing, at 42 x 16T, equating to a nominal 69.7 inches, with 700 x 28C tyres.

Kona Paddy Wagon

Paddy Wagon close-up

Paddy Wagon close-up

Paddy Wagon close-up

Paddy Wagon close-up

Kona Paddy Wagon (2008), in standard trim.

There are many other single-speed bikes available ready-built, including the Specialized Langster, Pearson Touché, and a whole range from Condor Cycles that culminates in a titanium-framed beauty.

Specialist dealers and sites include a single-speed MTB FAQ, On-One (England), Harris Cyclery (MA, USA), Condor Cycles (England) and singlespeed.net.

How slow is a single-speed?

One of the most bizarre things about riding single-speed is the discovery that their is little or no relationship between the number of gears that you have and your average speed. Even on quite hilly routes, I average similar speeds on either of my single-speed bikes compared to my Giant TCR C2 (20 gear) or LeMond Tourmalet (27 gear).

cowleaze profile C2

cowleaze profile ss

Shown above are my speed profiles for two training runs over a hilly route (note that whilst the X axis and Y axis speed scales are comparable, the Y axis altitude scale is slightly different). The major hill shown is Cowleaze, 1.7 km at an average gradient of 7% and a maximum of 12%, giving a total of just under 120 m of climbing. On my carbon-fibre 20-speed Giant TCR C2, I took 6 minutes 50 seconds, plus one stop to find my legs again, averaging 14.9 kph. On my modified Giant Bowery single-speed, I took 7 minutes and 5 seconds, plus one stop, averaging 14.3 kph.

The second series of ascents is Mitchell Avenue and the climb up from Ventnor, 1.2 km at an average gradient of 6% and a maximum of about 14%, giving a total of about 70 m of climbing. On the C2, I took 5 minutes 5 seconds (no stops), averaging 14.3 kph, whilst on single-speed, I took 4 minutes 42 seconds, averaging 15.1 kph.

On 5.2 km of a mixed, undulating training route (Princelett Shute to the White Lion, Arreton), with one short steep climb rising to a maximum gradient of about 12%, but an overall climb of about 70 m, the C2 was slightly quicker than single-speed: 9 minutes 44 seconds against 10 minutes 37, or average speeds of 32.1 kph (C2) versus 29.4 (single-speed).

Look back at the average race times for the Tour de France or Paris-Roubaix, and you will be surprised to see that the introduction of derailleur gears in the 1930s did not result in a step improvement in performance, but the continuation of a secular increase in average speeds that had started earlier.

mean speeds

These plots show a 5-year moving average (to smooth out individual variation from year to year) of the winners' average speeds for the two events. The X axis is time in years from inception, with the highest value representing 2007. The Y axis is average speed in km per hour. In the case of the Tour, speeds really started to increase when team tactics, the peloton, and similar organisational changes developed, in the 1920s, with 1927 showing a marked improvement to nearly 27 kph. In 1936, the last year in which single-speed was mandatory, the winner's average speed was almost 30 kph. In the case of Paris-Roubaix, the secular trend was established in 1922, when the winner's average speed reached nearly 35 kph, and from 1931 average speeds commonly exceeded 35 kph although single-speed bikes were still dominant. It was not until after the Second World War that winnings speeds were fairly consistently above 35 kph. I do not know when derailleur gears were first allowed or successful in Paris-Roubaix, but a new book due in October 2007 may help clarify that.

This always assumes that, like the pros of the past, you use an appropriate gearing on your single-speed for the route. The bikes shown above are geared for undulating road work, not major hill climbs, and should perform very usefully on the flat too. Most single-speed bikes are initially set up for that, using gears that are equivalent, around the 70 inch mark, such as 42 x 16, 45 or 46 x 17, 48 x 18, or so. At a cadence of 80 per minute, these will travel at around 17 mph, reaching 21 mph at 100 per minute, 25 mph at 120 per minute, and topping out at about 30 mph with your pedals spinning at 150 per minute. On hills, a cadence of 40 per minute equates to about 8.5 mph, so you should be able to pedal comfortably up 3% gradients, cope with an average gradient of about 6%, but above about 8% you will find it harder to keep your bike moving. The maximum gradient that you are likely to be able to ascend for a short distance is 12-15%. If you want to be able to ride up steeper hills, then you will have to increase the size of the sprocket on your freewheel, or reduce the size of your chainwheel.

You can do this in the traditional fashion by mounting a second single-speed freewheel (or a simple fixed sprocket) on the other side of your rear hub. Ideally you would want a hub that is threaded for freewheels on both sides (please send me one if you find such as beast!). However you can mount a single-speed freewheel on the side threaded for a fixed sprocket, although it will not actually have contact with the hub over its entire inner surface, which is perhaps not ideal. The snag with putting a different sized sprocket is that when you flip your rear wheel over to engage it, you may be unable to adjust the chain tension sufficiently. So this is definitely something to practise at home before you try it for real.

You also will need a stout spanner to release your wheel-nuts, although single-speed riders get used to carrying one around with their puncture repair kit. Slim lightweight spanners will not do if you tighten your wheel-nuts properly: you will need a substantial spanner with a broad business end.

If you intend riding an unusually hilly route, you might want to prepare your bike as if you were entering a competitive hill-climb, selecting the right gear ratio for the job. As it is usually harder to find a suitable range of freewheel sprockets than chainwheels, you may find it easiest to keep a selection of chain wheels ready for those special rides.

 

 
  © 2005-2007 EHN & DIJ Oakley