E-bike drivetrain upgrade promising accurate alignment and reliable pairing with KMC chains, the KMC Chainring targets riders who want quieter, more predictable shifting and neater installation. Solid construction and a spacerless-friendly layout reduce workshop time and roadside faff. Is this the right fit for a Bosch Gen 4 setup and a longer-lasting drivetrain?
⚡ At a Glance
- • Chainline Accuracy: Direct Mount with 7.0mm Offset maintains consistent chainline under load
- • Best for: Owners of Bosch Gen 4 Performance Line CX and Speed motors using KMC e-bike chains
- • Not ideal for: Riders with non-Bosch or older motor platforms without confirmed compatibility
Compatible with Bosch Gen 4 Performance Line CX and Performance Line Speed from MY2020. Matches KMC e-bike chains and is engineered for a minimum 3500km service life when paired correctly.
Precise chain alignment, with Direct Mount and 7.0mm Offset
Direct Mount interface positions the ring with a fixed 7.0mm offset, limiting lateral deviation and keeping the chainline true under pedalling loads. Accurate tooth placement reduces side-to-side movement and helps the drivetrain track correctly.
Consistent alignment reduces chain wear and keeps shifting smooth and quiet during climbs and hard efforts.
Tidy, straightforward installation, with spacerless-friendly design
Spacerless mounting removes the need for additional spacers and lowers stack height at the crank interface; user feedback notes a spacerless layout for neater assembly. Direct Mount geometry simplifies positioning during fitment.
Faster workshops and cleaner-looking drivetrains, useful for riders who service their own bikes or want minimal setup fuss.
Long-lasting pairing, with dedicated KMC e-bike chain compatibility
Designed to work specifically with KMC e-bike chains, including e1, e8, e9, e10, e11 and e12. Manufacturer guidance recommends pairing with an appropriate KMC chain to achieve a minimum service life of 3500km.
Matched chain and ring reduce premature wear and cut down frequency of replacements when the correct KMC chain is used.
✨ The 4 Key Reasons for KMC Chainring
- Bosch Gen 4 compatibility, secures direct fit on Performance Line CX and Speed motors
- KMC chain matching, prolongs chain and ring life when matched with KMC chains
- Spacerless-friendly layout, simplifies installation and keeps the chainline tidy without spacers
- Durable black finish, conceals grime and resists everyday wear during regular use
📋 Technical Details at a Glance
- Category: Sports, E-bike drivetrain component
- Brand: KMC
- Compatible motors: Bosch Gen 4 Performance Line CX and Performance Line Speed (from MY2020)
- Tooth count: 38T
- Chainline: 50.0mm
❓ Frequently Asked Questions
Q: Is the chainring compatible with my Bosch motor?
A: Designed specifically for Bosch Gen 4 Performance Line CX and Performance Line Speed motors from MY2020, compatibility with other motor generations is not specified.
Q: Which KMC chains should be used with the ring?
A: Matches KMC e-bike chains including e1, e8, e9, e10, e11 and e12; pairing with a recommended KMC chain aims for a minimum of 3500km service life.
Q: Is installation difficult for home mechanics?
A: User feedback highlights a spacerless-friendly layout that enables easier installation and a tidier setup, while Direct Mount geometry helps ensure correct alignment.
🏆 Our Verdict
The KMC Chainring is suitable for e-bike riders running Bosch Gen 4 Performance Line motors who want reliable shifting and low-maintenance drivetrains. Precise chainline via a 7.0mm Direct Mount offset and dedicated compatibility with KMC e-bike chains are the main selling points. While upfront investment may be higher than generic rings, the matched pairing and robust construction deliver better long-term value through reduced wear and fewer replacements.
