When I first started cycling road bike gears were always a topic of conversation. But now, as a cycling coach I only occasionally discuss gear choice with riders. This is undoubtedly becasue the number and range of gears on a bicycle has increased considerably. Consequently most riders have more than enough choice for a race.
I do like to look at old magazines, books and video as I am curious to see how bike gears have developed since I first started riding. It can be useful to remember old ideas and how to resurrect those that may still be relevant today. I recently spent some time looking at some coaching books I had bought in the 1980’s and found myself thinking about gearing and how it has changed since people started racing bikes.
The development of gear choice has been driven both by the development of technology that has provided a wider range and number of possible gears but also the practice of road racers keen to optimise their physical attributes. I do not intend to discuss technological developments in great detail as I would like to focus on the choice of ratios but a brief history helps to provide some context.
Single speed era
Early safety bicycles were single speed machines with, at most, a choice of two gears. Separate sprockets were mounted on opposite sides of the rear hub. A change of gear was made by removing the rear wheel and refitting it in the opposite direction. The so-called flip-flop hub.
The choice of two sprockets solved the practical difficulty of having a bike that may be severely under or over-geared when riding in hilly or mountainous terrain. But with choice limited to two ratios gearing was far from optimal and mostly a compromise
Internal hub gears
During the early part of the 20th century internal hub gears were invented and grew in popularity. However, not amongst racing cyclists. They were heavy and mechanically inefficient so were generally spurned by racing cyclists demanding light weight and speed. With up to 14 gears, efficiency close to that of derailleur gears, ease of use, and minimal servicing, modern internal hub gears are an attractive choice for commuters and cycle tourists. However, heavy weight combined with difficult wheel removal means they are hardly ever fitted to road race bikes.
The derailleur
The derailleur has a surprisingly long history with three surviving records of patents submitted during the 1890’s detailing rudimentary derailleur mechanisms. The concept rapidly grew in popularity but until the mid-1930’s one was never raced in the Tour de France. The Tour’s founder, Henri Desgrange, took exception to it’s use claiming variable bike gears were ‘only for people over the age of 45.’ The derailleur finally made its Tour debut in 1937 heralding a period of experimentation with derailleur technology and gearing that continues to this day.
Spinning
Spinning a bike gear is an important skill learned at a young age. However it can still be successfully taught to an older rider with little cycling experience. Accelerating to close gaps within the peloton or attacking an opponent with a fierce increase in speed is more easily achieved with a smaller ratio and fast cadence. But spinning also has additional psychological benefits.
To generate greater speed a cyclist has to increase the power delivered to the rear wheel. Power (measured in joules/second or Watts) is the rate of doing work and is calculated as the product of force (in Newtons) and distance moved (in metres). Consequently a cyclist can produce the same power output in different ways: either by pedalling rapidly in a low gear or more slowly in a high gear. In the low gear less force is applied to the pedals than with the high gear and this affects muscle fibre recruitment.
The tension that is produced in the muscle determines the fibres that are recruited. Fast twitch anaerobic fibres are recruited when the applied force (and muscle tension) is high. Conversely when force (and tension) is low, aerobic slow twitch fibres are the default choice. Slow twitch fibres are much more fatigue resistant. It therefore makes sense to spin a bike gear and conserve the fast twitch fibres for when a sudden burst of power is needed. For example, when attacking on a short climb or sprinting for the finish line. This is why, during the slower parts of a race, you will see road racers comfortably spinning an easy gear preserving their energy for the tactically important parts of the event.
historic choices of bike gear ratio
Prior to the 1950’s 52×15 (7.21m – a gear can be defined by the distance moved by the bicycle with one rotation of the crank) was thought to be a sensible upper ratio. For example, Marcel Kind won Paris-Roubaix with a maximum ratio of 49×16. In1948 Louis Caput rode with 49×15; however at the finish he claimed the tailwind was such that he could have ridden with a 50 tooth ring. Kind’s bike was fitted with a double front chainring (51/48) and a four speed freewheel (15-18).
For the 1950 Paris-Tour, the eventual winner André Mahé started with what was regarded a radical set up of a 52×14 top gear. The maximum gear selections of Coppi and Mahé were starting to move closer to what we are familiar with today, albeit the range of gears is much less.
Ratios then started to grow rapidly with Anquetil winning the 1957 and 1961 Grand Prix des Nations with 54×14 and 52×13, respectively. Poulidor won in 1963 with front rings of 53/49 and a rear block of 13-17. Freddy Martens pushed the limits further with 55×13 in 1976 and the 1979 winner, Bernard Hinault, 53×12 (55/46 front rings and a 12-17 block).
Hinault’s bike gears
In Bernard Hinault and Claude Genzling’s book Road Racing: Technique and Training, Hinault describes the evolution of his bike gears. He started out as a youth rider using 50×16 maximum gear and during his junior years never exceeded 51×14. This was despite there being no gear limit. As a professional his gears were much bigger with a 53 front ring and occasionally a 54 or 55. His ratios at the lower end did, however, reduce during his career. During mountainous races he rode a 22 in his early years progressing to a 24 so he could remain seated for longer when climbing. Contrast this with Froome’s gearing for the Tour of the Alps: 52/38 and an 11-30 cassette and it is clearly evident that what was considered a small ratio back in the 80’s is much larger than the choice of professionals today (3.67m compared with 2.67m).
These higher climbing gears during the 80’s were partly dictated by the available equipment but the prevailing view at the time was that a 23 sprocket was adequate for all but the steepest of climbs where a rider may choose a 24, 25 or 26. Remember, this was paired with nothing smaller than a 42 front ring or, very rarely, a 41. Merckx apparently often rode hilly races with 52/44 and 13-21 speed block. The recommendation for a very hilly one day race in the 1980’s was to swap the 21 for a 22 or 23 and pair it with a 42 front ring, much higher than the lowest gears of today.
my own bike gears
From my own experience, gearing options and fashion progressed slowly from when I started cycling in the early 1980’s. My first proper 12-speed lightweight race bike was a Raleigh Competition with 52/42 front rings and a 13-21 block. The range topping Team Replica came with a tighter ‘straight-through’ 13-18 block. Clearly softer amateurs needed a sedate 21 over a manly 18!
The range of available ratios increased gradually with the advent of 8, 9 and 10 speed cassettes. During the 90’s my lowest sprocket on the rear increased from 21 to 23 and the highest to a 12. By the late 90’s and early 00’s the 42 on the front had become a 39 and the 52 a 53. Into the 00’s and I had an 11-25 cassette and then, a decade later, the 11-speed cassette heralded 11-28 on the rear, almost as standard. My highest bicycle gears have progressed from 8.39m to 10.12m and my lowest from 4.2m to 2.92m, quite a difference.
Of course, a much larger range of bike gear ratios had always been possible on touring or recreational bikes. However, this involved the use of large capacity rear derailleurs and heavy triple chain sets. The development of compact and semi-compact drivetrains made possible new gearing options and led to much greater creativity from manufacturers.
1x bike gears
SRAM is probably one of the most innovative manufacturers in terms of gearing. It brought a specific 1x (single front chainring) option to cyclocross and then the road. Medium and long cage derailleurs can be paired with cassettes with massive ranges from 10 to 36 tooth sprockets, far more than could have been dreamt of only a decade ago. SRAM claims that with a single 48 tooth chainring and a 10-33 cassette the same range can be achieved as a 2x drivetrain with a 53/39 chainring and an 11-26 cassette. The advantage is lighter, simple set-up, but at the cost of suffering some larger jumps between the bigger sprockets.
It makes me wonder if nowadays we have got a little too sensitive to having precisely the right ratio at the right time. I am curious as to what a pro from the early to middle 20th Century would have made of a bike with 12, or even 13 sprockets, on the rear cassette and a gear range far in excess of anything available during their era. I am sure they would have swapped their bikes in an instant for the improved climbing ability and greater efficiency of current 1x set-ups, albeit with some jumps between sprockets.
back to 2x bike gears
Having made the case for a single ring on the road SRAM now offers innovative double chainsets. For example, a 10-33 cassette can be paired with 48/35 or 46/33 chainrings to give a decent range but without such large jumps between the lower climbing gears.
Some may argue that bike gear choices have become a bit of a marketing gimmick. It is true that manufacturers sell their drive chains on the promise that they are light, convenient, offer a gear for every occasion and consequently provide a more enjoyable and satisfying cycling experience. Gimmick or not the reality is that nobody wants to ride a bike uphill and feel their knees will pop from their sockets and competitive cyclists do not want to run out of gears during a crucial moment in a race. Current trends aside, cyclists have been experimenting with gears for over a century. With new technological developments I imagine they will do the same for years to come. That is until somebody invents a lightweight, efficient, wide-ranging progressive bicycle gear box with offers infinite variable ratios. I expect it will only be a matter of time.
