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How to compare an IGH (Shimano Alfine 11) with a 10 speed cassette and 3x chainwheel?

6 min read

Asked by: David Santiago

How do you compare gear ratios?

The best way to compare chainring and cassette combinations between bikes is to check their gear inches. They’re very easy to calculate: it’s the diameter of the wheel, times the size of the front chainring, divided by the size of the rear cog.

What gear ratio is best for climbing?

The best mountain bike gear ratio for climbing is 46 to 49 on a chainring and 16 to 18 on a cassette. For more diverse rides, mountain bike gears of ratios 46/17 to 42/17 are what work for flatter terrain or occasional hills. However, with that being said, the perfect ratio usually depends on the terrain you’re riding.

How do you count cog teeth?

Teeth & Bike Gear Ratios Explained



The chainring (front) on my bike is 50/34T. That means the outer ring has 50 teeth and the inner ring has 34 teeth. The rear cassette is 11 speed 11-32. This means there are 11 cogs ranging from 11 teeth up to 32 teeth (the exact cogs are 11/12/13/14/16/18/20/22/25/28/32).

How do you calculate gears on a bike?

To find this: divide the number of teeth on the chainring by the number of teeth on the sprocket; multiply by the wheel diameter (as with gear inches); then multiply this figure by pi (3.14) and convert to metric.

How do you calculate gear ratio with multiple gears?

You just count the number of teeth in the two gears and divide. So if one gear has 60 teeth and another has 20, the gear ratio when these two gears are connected together is 3:1.

What gear ratio do pro cyclists use?

Pros often use a 55×11-tooth high gear for time trials. On flat or rolling stages they might have 53/39T chainrings with an 11-21T cassette. In moderate mountains they switch to a large cog of 23T or 25T. These days, they’ve joined the big-gear revolution like many recreational riders.

What size cassette is best for hill climbing?

For hill climbing and mountainous terrain, we recommend a road cassette such as the 11-32T SRAM Red 22 XG1190 11 Speed Cassette (A2), or the 11-34T Shimano Ultegra R8000 11 Speed Cassette.

What size chainring is best for climbing?

Mountain bike chainrings are available in smaller sizes all the way down to 26t, though I’d recommend most riders try a 30t or 28t first to experience how much easier it is to climb. For gravel bikes, I wouldn’t recommend going any smaller than 38t to maintain top-end speed on downhills.

Which gear is best for cycling uphill?

Low Gear = Easy = Good for Climbing: The “low” gear on your bike is the smallest chain ring in the front and the largest cog on your cassette (rear gears). In this position, the pedaling will be the easiest and you’ll be able to pedal uphill with the smallest amount of resistance.

What is the best chainring combination?

Standard Setup. Currently, the most common gearing setup on new road bikes is a 50/34 chainset with an 11-28 cassette. This means that the big and small chainring have 50 and 34 teeth, respectively, and the cassette’s smallest cog has 11 teeth and its largest cog has 28 teeth.

Is an 11 34 cassette good for climbing?

All other things being equal, the 34T sprocket on the 11-34T cassette is going to give you the easiest gear. If your bike is currently fitted with an 11-28T cassette, switching to an 11-34T cassette will make climbing less of a struggle.

How do I choose chainring size?

The larger chainring gives you bigger, harder to turn gears that move you further per pedal revolution – so it’s suitable for higher speeds – while the smaller chainring gives you gears that are easier to turn but move you a shorter distance per pedal revolution – so it’s suitable for lower speeds, including riding

How do you calculate 3 gear ratios?

To calculate the gear ratio:



Divide the number of driven gear teeth by the number of drive gear teeth. In our example, it’s 28/21 or 4 : 3. This gear ratio shows that the smaller driver gear must turn 1,3 times to get the larger driven gear to make one complete turn.

What is the speed ratio formula?

To calculate speed ratio, otherwise known as gear ratio, you divide the number of teeth of the input gear by the number of teeth of the output gear.

Does a higher gear ratio mean more torque?

Gear ratios are what engineers call “torque multipliers.” Higher numbers give more torque more quickly to allow better acceleration. Let’s compare that to, say, an early 1960s Ford truck transmission, with fourth gear at a 1:1 ratio, third at 1.69:1, second at 3.09:1 and first at a very short 6.32:1.

What is a 5 to 1 gear ratio?

For example, if a motor drives a 12T gear to a driven 60T gear on an arm, the 12T driving gear has to rotate 5 times to rotate the 60T driven gear once. This is known as a 5:1 ratio. The torque output is 5 times as much, however, the speed output is only 1/5.

Is it better to have more or less gears for racing?

In top gear, your car is working too hard to overcome a gearing disadvantage (higher gears mean less wheel torque) to accelerate. The more gears a transmission has, the more flexibility it has to find the most efficient engine speed for a given wheel speed.

How does the gear ratio work?

A gear ratio is the ratio of the number of rotations of a driver gear to the number of rotations of a driven gear. A colon is often used to show a gear ratio: gear ratio = rotations of a driver gear : rotations of a driven gear. For every rotation of the 45-tooth gear, the 15-tooth gear must rotate 3 times.

What gear ratio is best for torque?

With a 4.30 ratio, it turns 4 1/3rd times for every revolution of the rear wheel. The numerically higher gear ratio (in this case, 4.30) increases wheel torque and improves acceleration from low speeds.

What gear ratio is best for street racing?

If we have a daily driver, 2.55 to 3.25 gear ratios typically work best, whereas a street/strip application we would usually use a 3.42 to a 3.90 gear ratio, and race applications most commonly use a 4.10 and above gear ratios.

What axle ratio is best for speed?

Performance: Looking again at the ratios used above, the higher 3.55 ratio indicates faster acceleration whether the truck’s empty or loaded. The higher the ratio, the more revolutions per minute. Towing: For pickup trucks released after 2010, the best axle ratio for towing falls somewhere between 3.55 and 3.73.