Wednesday, 28 November 2012

Some general randomness

I had a lovely ride into work this morning. One of those rides where everything seems easy, one's mood is positive and the miles fly by. It was in high spirits that I sat at my desk this morning with my usual banana and mug of tea. Even the prospect of an exceptionally dull day at work was not enough to break the spell!

When I used to run a lot, folk talked about the "runners' high" - the rush of feel-good, pain-killing endorphins that comes after exercise. No one really mentions a "cyclists' high" but there is a definite feeling of all being rosy and right with the world after even a short ride.

People pay good money to bad people or need a prescription to feel this good. When all you have to do is get out on your bike and get pedalling, it seems almost too good to be true.

Having used my large-wheeled, multi speed hybrid for a few weeks, I mused as I pedalled this morning some of the main differences between it and my Dahon.

Gear inch calculations show that, on paper, there shouldn't be much difference in speed between the two bikes. In truth, the hybrid is a bit faster and I think this is for a couple of reasons:

Narrower gaps between the gear ratios mean that one can maintain a particular cadence under most conditions by going up or down the gears. That is, after all, why they were invented!

Greater inertia from the larger wheels means that when coasting (or at a more micro level, between power strokes on the pedals) the bike carries itself forward better i.e. it slows less. This seems particularly so when grinding uphill or pushing into the wind.

However, though it may be a bit faster, it's not by a large margin. The minutes saved on my reasonably modest commute don't add up to much and anyway, who's racing? Besides, the lower weight of the Dahon make it much nippier and, well, just more fun to ride!

I have waxed lyrical about gearing a few times before and had planned to mess about with the Dahon's gears some more. However, I recently came across Justin Simoni's website ( He seems like a pretty serious cyclist having ridden the Tour Divide a couple of times (a 2,750 mile monster, unsupported mountain bike race) among other achievements. From his blog, most of his general riding (if you can call a 200 mile, mountainous, ultralight bike-packing trip "general") is done on a sort of single speed bike. Using a flip-flop hub and clever "dingle cog" arrangement he actually has (albeit with some mechanical messing about required) the choice of fixed and free in a few different ratios. What really interested me though, was that Justin's highest gear is set at about 60 gear inches. That's pretty low by geared bike standards and so it must be possible to spin along quite nicely at high speed in a low gear. Justin also wins races on this bike after all.

So it made me rethink. If such things are possible with relatively low gearing, I'm not going to mess with my Dahon's gearing for a while and just spin the pedals faster instead! It is after all supposed to be easier on the knees too.

I think when I'm managing 180 rpm with ease in top gear on the flat, I may have to rethink. But I doubt those days are just around the corner.

Happy spinning everyone!

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