Timing Yourself To Determine Gear Ratio/Torque

Question

Since there are so many types of bikes IGR, belt, and gears, I have resorted to doing timed runs with the bike to determine how high the torque is. I throw it into the highest gear and ride on flat ground.

If I wasn't comparing bikes I would just use the gear ratios or use a gear calculator(still confuses me slightly).

Is doing timed trials on the highest gear effective for determining which bike has a higher gear ratio? I gather I am not factoring in wheel speed differences considering some wheels are faster.

Alternatively a tool would be nice that would help but I am guessing they are rather expensive.

Answer 1

The gear ratio is simply the ratio of the number of teeth on the two cogs. If you can see the gears, you can compute it by counting the teeth and dividing. If you can't see the gears (e.g., an IGH), just measure how many times the rear wheel turns for one turn of the pedals (or, for more accuracy, do ten turns of the pedals and divide the answer by ten).

Time trials would be a terrible way to compute the gear ratio since there are so many uncontrolled variables and confounding factors. For example, a higher gear ratio would potentially give you a higher top speed but it would take you longer to get there.

It's not clear to me why you think that computing the gear ratio is important.

Answer 2

Answering this:

is doing timed trials on the highest gear effective for determining which bike has a higher gear ratio?

No, it isn't. At all.

The gear ratio is simply the number or teeth on the front sprocket divided by the number or teeth on the rear sprocket.

A more useful calculation is length units of development - how far the bike moves per revolution of the cranks - which takes driving wheel size into account, and allows comparisons between bikes with different wheels and tires.

Development is simply the gear ratio multiplied by the effective circumference of the driving wheel.