Reviews & Ratings
The reviewer discusses the ZTTO SLR Gen3 11speed Road Bike Cassette as a replacement for their worn-out monoblock steel cassette. They mention it is incredibly lightweight at just 122g and is the latest generation from ZTTO, referred to as the SLR Gen3. However, they express concerns about its durability, particularly due to the aluminum teeth on the first three sets, which they expect to wear out quickly. They plan to test it and provide updates on its performance.
AI-Summary
Pros
- Incredibly lightweight at just 122g
- Latest generation from ZTTO (SLR Gen3)
Cons
- Expected lower durability compared to the previous black cassette
- Aluminum teeth on the first three sets are expected to wear out very fast
- Suspects the underlying steel alloy is the same as the previous model
- Expects to get fewer miles (possibly less than 2,000) out of it
Key Points
- Weight: 122g
- Generation: SLR Gen3
- First three sets of teeth are milled out of aluminum
- Surface finish appears to be zinc plating
- Underlying steel alloy suspected to be the same as previous models
The reviewer discusses the ZTTO SLR Gen3 11-speed cassette as one of the most exciting upgrades made to their hill climb bike. They highlight its extremely low weight of 113g for the 11-28T version, which was a significant factor in their decision to purchase it. They note that the cassette's teeth are well-machined with proper Shimano-style ramps, resulting in brilliant shifting performance. However, they express concerns about durability since the top three sprockets are made from a single block of aluminum, suggesting it may not last long under heavy use. The reviewer clarifies that this is intended as a race-only cassette that won't see many miles, hoping it will last at least a season.
AI-Summary
Pros
- Extremely lightweight at 113g for the 11-28T version
- Teeth are well-machined with proper Shimano-style ramps
- Brilliant shifting performance
- Good value for a race-specific component
Cons
- Top three sprockets made from a single block of aluminum
- Durability concerns for long-term use
- Not suitable for high-mileage riding
Key Points
- Model: ZTTO SLR Gen3 11-speed cassette
- Weight: 113g for 11-28T version
- Construction: Top three sprockets are aluminum block
- Intended use: Race-only component
- Expected lifespan: Hoping to last at least one season
The reviewer discusses their experience with a cheap AliExpress cassette (likely the ZTTO SLR Gen3 based on context) that failed during a hill climb race. They mention the cassette started skipping under power, particularly when standing on steep gradients, which ruined their race performance. After replacing it with a Shimano 105 cassette, all issues resolved immediately. The reviewer reflects that while the lightweight AliExpress cassette (approximately 112g) offered weight savings, its unreliability outweighed any benefits. They acknowledge that sometimes budget components work, but this was a clear failure case.
AI-Summary
Pros
- Lightweight (approximately 112g compared to 300g for Shimano 105)
- Initially seemed like a cost-effective option
Cons
- Chain skipped repeatedly under power
- Made standing on steep gradients impossible
- Unreliable performance during critical moments
- Forced rider to sit and lose power
- Caused significant time loss in race
- Required immediate replacement
- Not as tested or designed as branded components
Key Points
- Approximately 112g weight
- Failed during high-power efforts
- Skipping occurred when standing on 20% gradients
- Replaced with Shimano 105 cassette (300g) which worked perfectly
- Purchased from AliExpress
- Described as a 'cheap bike component'
The ZTTO SLR Gen3 11speed Road Bike Cassette 11 Speed 11-30 11-32 11-34 11-36 11-28T 112g K7 11s Spokets HGR universal is not mentioned in this video.
AI-Summary
The reviewer analyzes the ZTTO SLR Gen3 11-speed cassette, focusing on a specific failure where the top two sprockets sheared off. They note the cassette is lightweight, visually appealing, and affordable. The design involves the top three sprockets milled from a single aluminum block with the rest being steel. The reviewer has used smaller versions (11-28T) for years without issue, but identifies a design flaw in larger sizes (11-30T and up) where the top two sprockets are connected by a thin ring of supports, creating a potential cantilever beam effect and stress risers. They attribute the specific failure to use on a rough cyclocross course with spiky power delivery. The reviewer concludes that these cassettes prioritize weight savings over durability and safety margin, advising caution with larger sizes.
AI-Summary
Pros
- Great looking
- Incredibly lightweight (e.g., 117g for 11-28T vs. 260g for Shimano 105)
- Affordable (about 60 quid)
- Shifting performance is 'really decent', about 90-95% as good as Shimano/SRAM
Cons
- Design flaw in larger sizes (11-30T, 11-32T, 11-34T, 11-36T) where top two sprockets are connected by a thin ring of supports, creating a weak point
- Risk of sprockets shearing off, especially under high, spiky loads (e.g., climbing out of saddle on rough terrain)
- Questionable safety margin due to extreme material milling
- Noisier than official Shimano cassettes during running
- Aluminum teeth on upper sprockets can snap if shifting under load, as aluminum is softer than steel chain
- Prioritizes minimal mass and competitive weight claims over long-term durability and high-cycle fatigue life
Key Points
- Brand: ZTTO
- Model: SLR Gen3
- Construction: Top three sprockets milled from a single block of aluminum, the rest is monolock steel
- Weight: 117g for 11-28T size
- Failure observed on an 11-36T cassette after ~150km while climbing
- Design varies by size: only the 11-28T version does not have the 'double stack' layout for the top two gears; larger sizes do, increasing risk
- Larger sprockets are more flexible/compliant, increasing failure risk
- Recommended for users who accept trading safety factor for weight savings
- Suggested alternatives: ZTTO cassettes milled from a single steel block with aluminum spider, or the older SLR Gen2 where only the largest sprocket is aluminum
Where to Buy

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