This post compares the advantages and disadvantages of 11-28 and 11-32 cassettes.
The Advantages of 11-32 Cassettes
- Lower Gear
The difference between the largest sprockets found on 11-28 and 11-32 cassettes is 4 teeth and results in substantially dissimilar gear ratios.
The term gear ratio indicates how many times the rear cog and consequently the rear wheel rotates per 1 rotation of the cranks.
To calculate the gear ratio of a certain combination, one needs the number of teeth on the chainring and the rear cog. For example, a 42T chainring and a 28T cog result in a 1.5:1 gear ratio.
Or in other words, the rear cog and consequently the rear wheel will rotate 1.5 times per 1 revolution of the cranks. Meanwhile, a 42T chainring + 32T cog offers a 1:1.3 gear ratio. This means that the rear wheel has to spin only 1.3 times for every rotation of the cranks.
The smaller the gear ratio, the less effort is required to spin the cranks because the rear wheel doesn’t have to make as many revolutions. (Hence why it’s so hard to ride uphill in high gear.)
- Equal Speed at a Higher Cadence
The lower gear makes it possible to reach and maintain speed while operating at a higher cadence (RPM). (Note: Higher cadence around 90 RPM or so is considered more efficient and energy preserving.)
This happens because the rear wheel is rotating fewer times per one revolution of the cranks. To reach the speed that one would have in a higher gear, the rider has to increase their cadence.
To calculate the speed of a bicycle one needs the following data:
- Traveled distance
- Time traveled
- Wheel Circumference
- Gear ratio
In the following examples, the wheel circumference is 2161mm (28-inch wheel). The gears are 42/28 and 42/32.
At 42/28 and 70 RPM, the potential speed of a bike is 13.48km/h.
At 42/32, the user can maintain 13.45km/h at 80 RPM.
- Better Compatibility With 1x Drivetrains
Since 11-32 cassettes come with lower gearing, they are not as limiting when the rider is relying on a single chainring (1x drivetrain).
- Better For Touring
Bicycle touring is about “resilience” rather than maximum efficiency such as maintaining optimal cadence at all times. If you’re in the middle of nowhere, and you end up facing a scary hill after a long day of riding, you will be happy to have a very low gear even if the jumps that lead to it are not as small as possible.
The Downsides Of 11-32 Cassettes
- Larger Jumps Between The Gears
The only characteristic of 11-32 cassettes that can be considered a downside are the larger jumps between the individual gears.
The tables below compare the gradations of 11-28 and 11-32 cassettes to illustrate the differences between the two.
Jumps In %
|Range||Speeds||Jumps In %||Average|
|Shimano||11-28||9||9%-8.3%- 7.69% -14.3%-12.5%-16.6%- 14.3% -16.6%||12.4%|
|SRAM||11-28||9||9% – 8.3%- 7.69% -14.3% – 12.5%- 16.6% – 14.3% -16.6%||12.4%|
Conclusion: On average, the jumps between the gears of 9-speed 11-32 cassettes are 1.6% larger than those of 11-28 cassettes.
Jumps In %
|Range||Speeds||Jumps In %||Average|
Conclusion: On average, the jumps between the gears of 10-speed 11-32 cassettes are 1.7% larger than those of 11-28 cassettes.
Jumps In %
|Range||Speed||Jumps in %||Average|
Conclusion: On average, the jumps between the gears of 11-speed 11-32 cassettes are 1.48% larger than those of 11-28 cassettes.
The data makes it clear that the jumps on 11-32 cassettes are not nearly as large as one might expect.
Moreover, the biggest jumps include the three largest cogs which aren’t used as much as the mid-ones. Thus, the cadence of the rider will not suffer dramatically.
- Not Compatible With Short Cage Derailleurs
A 32T cog is notably larger and therefore requires a derailleur with a longer cage. Another way to increase the capacity of the derailleur would be to get a derailleur hanger extender.
- New Chain
The large cog will require a longer chain. Thus, if you’re switching from an 11-28 or a smaller cassette, a new chain will be needed as well.
The Advantages of 11-28 Cassettes
- Smaller Jumps
As pointed above, 11-28 cassettes come with smaller jumps between the gears which make shifting transitions smoother. Conversely, larger jumps can keep the rider in the wrong gear for a longer period of time and thus hurt comfort and efficiency. (The effect, however, isn’t substantial.)
- No Unused Gears
While it’s great to have a very low gear such as 32, if it’s rarely used, one is getting only the negatives of 11-32 cassettes and none of the benefits.
For many people, 11-28 cassettes offer “just enough” low end to the point where an extra gear is considered needless/redundant.
- Great When Paired With Compact Cranks
Compact cranks come with a 34T chainring. A 34/28 gear offers plenty of range for most locations apart from extremely hilly regions. And since compact cranks have gained serious popularity, many users will find 11-32 cassettes unnecessary.
- Better For Racing
On the highest level, every single component of the bicycle is deeply analyzed and optimized as needed for maximum output. If a pro rider is unlikely to need a 32 cog for the terrain ahead, then you will not find such a cog on their bike. Instead, the mechanics will install a cassette with minimal jumps between the gears and cogs that will be used during the race.
In most scenarios, an 11-28 or a 12-28 cassette satisfy those conditions better than an 11-32.
- Extra Stamina
A while back I bought a retro road bike in excellent condition. It came with a 7-speed 13-23 Suntour freewheel and 52/42 chainrings. That’s a pretty high gearing by today’s standards, but since the bike was in good condition, I kept the original freewheel.
The bike isn’t a great climber, but it did force me to get stronger due to the lack of needless low gears.
I don’t know if you’ve heard of the Parkinson’s principle. Anyway, it goes as follows – work expands to fill the time allotted for its completion.
If a man is given 3 weeks to finish a task, he will take all 3 weeks to complete it even if less time is needed. If the timeline is expanded to 3 months, the work period will increase to 3 months.
We often observe something similar when it comes to cycling gears. Or in other words, the rider is likely to switch to an easier gear when pedaling becomes harder even though the task can be completed while pedaling in a higher gear.
The only way to ensure that the rider is pedaling in a higher gear is to eliminate the lowest.