Some Wonkishness On Bike Gearing

A long and longwinded post just to say that you’re not stuck with the gearing choices that your bike came with and that if you have a “road bike” you might want to consider lowering the gearing. 😉

A while back Guitar Ted wrote a post that mentioned that what we think of today as road bikes are really road racing bikes. You see that road racing focus cary over into other non-racing road bikes, or as I like to call them Good Basic Transportation, in a  few ways (mostly bad ways), the most noticeable of them being bike gearing (high) and tire widths (narrow).

Bike gearing is measured a few ways. I usually use speed at cadence which gives you how fast you’ll be going in a given gear at a given pedal cadence. Bike gears are denoted by how many teeth they have in them, always starting with the chainrings (gears in front)  and going from highest gear to lowest. For example: when I bought my bike it’s highest gear was a 50/11, meaning that the biggest chainring had 50 teeth and the smallest cog (gears in the back) had 11 teeth. Using speed at cadence we can see that pedaling as fast as I can, about 120RPM, with the bike in its highest 50/11 gearing I’m traveling at about 44MPH. There’s a bit of a problem with this as once I hit about 20MPH I generally coast. So… About half of my bikes gearing potential was largely unused. 34/32 was the lowest gearing on the bike meaning that I had to maintain about a 5MPH pace to stay in a high enough cadence to pedal comfortably, which is pretty much impossible to do while going up a steep grade with a trailer full of camping kit or groceries.

Like most “road” bikes my bike was way over-geared for how I actually road it and by “road” bike standards it came from the shop geared a little on the low side. After about 2 years of riding my bike with too-tall gears I got sick of it and headed down to my local bike shop to brain storm up a setup that was geared appropriately for the speeds I ride at and how I actually use my bike. You can see the results of what we came up with in the photos above. 44/34 up front and 12-36 in the rear. This means my bikes gearing “spins out” at about 36MPH, which is plenty fast for me. With a bottom gear of 34/36 I can spin at a comfortable rate up almost any hill whilst bringing home my groceries. It also means that where I previously wasn’t using a large chunk of my gearing I now use all my gearing which makes for more comfortable riding and means that I can ride further.

This change in gearing as been a huge improvement and didn’t even wind up costing me all that much, so win, win, win.

 

About Michael

A middle aged guy from a bit north of the middle of the country.
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