Flywheel Ultimate Guide: Cassette vs Rotary

In addition to integrated wheels and spoke wheels, ebike tires also have cassette flywheels and rotary flywheels. Cassette flywheels and rotary flywheels are widely used in speed change systems. Cassette flywheels and rotary flywheels are very different in structure, installation method and performance. This article will introduce in detail the differences between cassette flywheels and rotary flywheels and their applications.

1. Installation

Cassette flywheel: The cassette flywheel is installed on the rear hub through the cassette freehub. The flywheel group with different numbers of teeth can be replaced separately. The freehub can control the idling and power transmission during pedaling.

Threaded Freewheel: The rotating flywheel is an integral structure, which is directly screwed onto the threaded interface of the rear hub. Unlike the cassette flywheel, the rotating flywheel is an integral structure. The entire flywheel includes the ratchet and the flywheel gear. Once it needs to be replaced, it will be more troublesome and the entire flywheel needs to be replaced, which will be a large amount of work.

2. Structure and Maintenance

Cassette flywheel: The ratchet mechanism of the cassette flywheel is inside the freehub, and there is no overly complicated structure. The cassette flywheel is accepted by more riders for its simple structure and easy replacement, and the subsequent maintenance cost is very low, so riders are more inclined to use the cassette flywheel.

Rotary flywheel: The ratchet mechanism of the rotary flywheel is inside the flywheel. If it needs to be replaced, it needs to be replaced as a whole. In the past, the rotary flywheel was installed on relatively high-end ebikes, but now with the advancement of technology, the rotary flywheel is gradually being eliminated from high-end bicycles.

3.Weight and Efficiency

Cassette flywheel: Generally speaking, a cassette flywheel is lighter than a rotary flywheel because the freehub and flywheel are designed separately and the materials used are better. The cassette flywheel has a higher transmission efficiency because it is lighter.

Rotary flywheel: Different from the separate gears and freehub of a cassette flywheel, a rotary flywheel is generally integrated, so it is heavier, and because it is directly integrated, its efficiency is lower than that of a cassette flywheel.

4.Number of Gears

Cassette flywheel: Cassette flywheels are usually more suitable for high-performance mountain bikes, road bikes, hybrid bikes, and other high-performance ebikes. Cassette flywheels usually support 7-12 gears or more.

Rotary flywheel: Rotary flywheels are mainly found on low-end or entry-level bicycles. Rotary flywheels usually have 5-7 gears, which is a small number of gears and has an upper limit on the number of gears.

5.Market Positioning

Cassette flywheel: Cassette flywheels are common in mid-to-high-end electric bicycles. They are suitable for more professional and modern electric bicycles, adapted to more modern speed change systems, and have strong playability and controllability.

Rotary flywheel: Rotary flywheels are usually found on lower-end and older bicycle models and are rarely used on modern electric bicycles.

Conclusion

In summary, cassette flywheels are more common in modern bicycles because of their higher efficiency, lighter weight and more flexible gear selection. Rotary flywheels will gradually be eliminated in daily use with the advancement of technology.