ZTTO ULT2 12 Speed 11-30T 34T 36T Road Bike Cassette 11 steel with 1 AL Gravel Ultralight 12S Bicycle Freewheel 12V Sprocket

The ZTTO ULT2 12-speed cassette is praised for its extremely light weight and good value, but concerns exist about durability, especially in larger sprocket versions (30T+), with one reviewer analyzing a structural failure point. Shifting performance is considered decent, though not on par with major brands.

Pros

Extremely light weight.1 2
Good value for the price.2
Shifting performance is 'really decent' (90-95% of major brands).2
Visually appealing with nice colors.2

Cons

Potential structural failure point in the top two sprockets of larger sizes (30T, 32T, 34T, 36T).2
Design creates a cantilever beam effect and stress risers.2
Aluminum teeth can snap if shifting under load.2
Noisier than official Shimano cassettes.2
Durability not yet confirmed; reviewer needs more miles to be sure.1
Prioritizes weight saving over durability and safety factor.2

Key Facts

Larger versions (11-30T, 32T, 34T, 36T) have a 'double stack layout' for the top two sprockets connected by a thin ring of supports, increasing failure risk.2
The 11-28T version has a different, stronger web structure where only the largest sprocket uses thin support arms.2
Cassettes are CNC-milled from aluminum.2
Used on a sub-6kg climbing bike.1

Sources

1
Tom Bowers CyclingI Raced the Lightest Wheels I Own up a SAVAGE 24% UK Hillclimb
2
Trace VeloMy favourite AliExpress cassette might have a problem…

Reviews & Ratings

Tom Bowers Cycling

14:24

I Raced the Lightest Wheels I Own up a SAVAGE 24% UK Hillclimb

The reviewer uses a ZTTO ULT2 12-speed cassette on their lightweight climbing bike, noting it is extremely light and a good compromise between weight and durability, but they need more miles to fully evaluate it.

July 07, 2026Watch on YouTube

Trace Velo

09:52

My favourite AliExpress cassette might have a problem…

The reviewer analyzes a failure of the ZTTO ULT2 cassette, specifically the 11-36T version, focusing on a design weakness in the top two aluminum sprockets. They explain the structural and use-case factors that likely led to the failure and compare the design across different cassette sizes.

February 19, 2026Watch on YouTube

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