The ZTTO Ultraight cassette offers exceptional weight savings and value, but durability concerns, especially in larger sizes, due to aluminum construction and design flaws.
Pros
- Lightweight (lighter than Dura-Ace)
- Good value for money
- Decent shifting performance (90-95% of major brands)
- Visually appealing color options
Cons
- Potential structural failure in larger sizes (11-34T, 11-36T) due to design
- Sharp internal edges and 90° corners act as stress risers
- Thin support arms create cantilever beam effect on top sprockets
- Larger sprockets more flexible, increasing failure risk
Key Facts
- Weight: 165 g for 11-32 12-speed (Ultimate Gen 2 model)
- Construction: All steel except largest sprocket (aluminum) in Gen 2; other versions CNC-machined aluminum
- Design differs by size: 11-28T safer than 11-34/36T which have thin support arms and stress risers
Reviews & Ratings
The reviewer discusses the ZTTO Ultraight 11/12 Speed Road Bike Cassette, specifically the 'Ultimate Gen 2' model. They note it is lighter than Dura-Ace, costs only a quarter of the price, and is entirely steel except for the final sprocket which is aluminum. They have about 400 km on it and find its performance on par with Dura-Ace, provisionally rating it S tier pending further durability testing.
AI Summary
Pros
- Lighter than Dura-Ace (165 g for 11-32 12-speed)
- Only a quarter of the price of Dura-Ace
- Performance on par with Dura-Ace so far
- Entirely steel except for the largest sprocket (aluminum), promising good durability
Cons
- Durability not fully tested (only 400 km)
- Provisional rating; may be downgraded after more testing
Key Points
- Model: ZTTO Ultimate Gen 2
- Weight: 165 g for 11-32 12-speed cassette
- Construction: All steel except final sprocket (aluminum)
- Price: About a quarter of Dura-Ace (approx. 80-100 GBP?)
- Reviewer has 400 km of use on main race wheels
The reviewer analyzes the ZTTO Ultraight cassette, focusing on a structural failure in the 11-36T version. They explain the design flaw, compare it to the more robust 11-28T version they use, and discuss how use case and sprocket size affect failure risk. They conclude these cassettes prioritize weight over durability.
AI Summary
Pros
- Lightweight (prioritizes minimal mass)
- Visually appealing with colors
- Good value (built to a price point)
- Shifting performance is decent (90-95% of major brands)
Cons
- Potential structural failure in larger sizes (11-34T, 11-36T) due to design
- Sharp internal edges and 90° corners act as stress risers
- Thin support arms create a cantilever beam effect on top sprockets
- Larger sprockets are more flexible, increasing failure risk
- Noisier than official Shimano/SRAM cassettes
- Aluminium teeth can snap if shifting under load
- Questionable safety margin due to extreme material removal
Key Points
- Failure observed on an 11-36T version used in cyclocross.
- Design differs by size: only the 11-28T version has a safer design where only the largest sprocket uses thin support arms.
- Larger sprockets act as longer lever arms, increasing peel-off forces.
- Use case matters: spiky power delivery on rough terrain stresses the cassette more.
- Cassettes are CNC-machined from aluminium, pushing material limits.
- Recommends steering clear of the 11-36T and 11-34T versions.
Where to Buy
ZTTO Ultraight 11 12 Speed Road Bike Cassette 11s 12s 11-28/30/32/34/36T ULT Sprocket 11s 34T Gold Flywheel 11V 12V Gravel K7 HG
Questions about ZTTO Ultraight 11 12 Speed Road Bike Cassette 11s 12s 11-28/30/32/34/36T ULT Sprocket 11s 34T Gold Flywheel 11V 12V Gravel K7 HG
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