In praise of the smaller "big" ring - Road Cycling UK

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In praise of the smaller "big" ring

45/34 chainrings

One needs to temper one’s enthusiasm when the RCUK editorial hand is proffered holding test equipment , for two reasons. Firstly, there’s the not unreasonable fear of how people will react to your opinion and analysis. Secondly, the product’s gravitational slide through the RCUK hierarchy has ended at your door. Why? Take, for example, the recent kind offer of a 45 tooth outer chainring just prior to our recent autumn tour. My immediate thought, perhaps cynical, was that RH was somehow rather unsubtly referring to my lack of fitness. As the thought was swiftly removed on seeing the topography for the first two days’ routes, my confidence was reinforced with the unveiling of Richard’s steed complete with no less than another 45 chainring.

Not withstanding reassuring myself with the adage that “what’s good for the goose etc.”, I somehow had fallen yet again under the subversive influence of the ‘Pheasant.’ I envisaged that, by fitting a smaller outer chainring, I’d be enjoying an easier ride through the ‘mountains’ of south Devon, whereas in reality a great deal of my time on those two days was spent twiddling the standard 34 inner ring. Was the offer of a 45 in fact a cunning ruse to divert attention from his real plan, which was none other than the sustaining of a punishing pace across the Somerset levels and on to the Berkshire Downs and beyond without a single recourse to the inner ring?

Now back safely to the routine of my regular rides and, relieved of the 45, reacquainted with the 50, I find myself questioning the industry standard chainring sizes, to the extent that, racing aside, I feel maybe we would all benefit from different ratios. At no point during the tour, on which, admittedly, luggage played a part, did I feel the desire or need for bigger gears. My real requirement was to access gear ratios that allowed a relaxed pedalling cadence over a variety of terrain. If I’d just dropped in from Mars and had no preconception of road bike chainring sizes, the 45/34 would have felt as good as any.

Until the ‘90s everyone in this country rode around with ring sizes of 52/42 unless an ardent tourist. Blocks [multiple freewheels – ed.] were six or seven speed and anyone turning up with a larger rear sprocket than a 21 would be laughed out of the back of the bunch, training rides not withstanding. Since then Continental influence has seen an increase to a 53 outer chainring and a smaller 39 for the inside with compact 50/34 as the alternative for sportives and touring.

Coupled with technical advances and 10 or 11 speed cassettes, these chainring standards supply a vast combination of cycling ‘inches’. The questions for me are, do we use them, are they relevant to most daily scenarios and, importantly, does the combination of chainring and sprocket size place the chain in the most efficient place while riding in a preferred gear?

Looking back now at the effect of the old school 52/42 ratios on a winter of training and club runs, I am reminded that it meant that every spring saw a renewal of the 42 chainring and the replacement of the middle sprockets, 18, 16, 15, equating to gears of between 63 and 76 inches. Today, using the sportive influenced sizes of 50/34, my gear choice invariable sees the 50 ring in action with the 17 to 21 sprockets, giving a gear of 64 to 79 inches.  

All that technical progress for a relatively unchanged cadence and gear requirement. However, using a 45 or 46 outer places the chain centrally within the cassette and enables better drive from the larger ring, unlike on a 50/34 or even 53/39 where I suspect a lot of people end up in either the lower or higher third of the block depending on their choice of large or small chainring. And 45×11 is the same as 52×13; high enough for most.



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