Standard cassettes have uniform tooth shapes. The ZIP uses a variable geometry where every fifth tooth is 0.2mm taller and offset. This "altered" tooth catches the chain only under load, preventing the dreaded "chain suck" that plagued earlier prototypes.
The 2021 edition of the Altered Cycle ZIP represents a refined approach to cold-weather riding. Designed for the dedicated cyclist who refuses to let sub-10°C (50°F) temperatures dictate their training, this jersey bridges the gap between a traditional thermal long-sleeve and a softshell jacket. It prioritizes core warmth, moisture evacuation, and a race-oriented fit without the bulk of a taped winter jacket. altered cyle zip 2021
I spent three months in 2021 testing the Altered Cycle ZIP on a mid-travel Santa Cruz Tallboy. Here is the unfiltered verdict. Standard cassettes have uniform tooth shapes
The Altered Cycle ZIP 2021 represents a fork in the road for drivetrain design. While the rest of the industry chased wireless, app-controlled, servo-driven shifting, Altered Cycle doubled down on physics, metallurgy, and raw tactile feedback. It is flawed, heavy, and noisy—but it is also the most reliable mechanical shifting system ever built for high-power riding. Keywords: altered cyle zip 2021, altered cycle zip
Whether the brand ever returns to production remains a mystery. For now, the 2021 ZIP lives on as a testament to what happens when engineers refuse to follow the herd. If you see one for sale, grab it. Just don’t forget to buy the chain.
Keywords: altered cyle zip 2021, altered cycle zip cassette, 2021 mechanical drivetrain, belt-drive shifting, high-torque bicycle cassette.