ROCKBROS Gravis 20inch Folding Bike 9-Speed Hydraulic Disc Brake 4130 Steel LUG
This page is affiliate-supported. Prices and availability can change after the last marketplace refresh.
About this product
The ROCKBROS Gravis 20-inch Folding Bike is equipped with a 4130 Cr-Mo steel frame featuring LUG construction and a 9-speed MicroSHIFT ADVENT drivetrain. This unisex adult bicycle comes with dual-piston CNC machined aluminum hydraulic disc brakes, utilizing 160mm front and 140mm rear rotors. It is designed with 20-inch tubeless tires, an aluminum folding stem, and includes features like an adjustable seat and quick-release seatpost clamp. A 3-year manufacturer warranty backs this model, which has a 150cm item length.
Our take
I'm impressed with the feature set of the ROCKBROS Gravis folding bike, especially the robust 4130 Cr-Mo steel frame, which provides a solid foundation. The 9-speed MicroSHIFT ADVENT setup is a reliable drivetrain choice, perfect for navigating varied urban terrain. The dual-piston hydraulic disc brakes are a fantastic inclusion, offering confident and consistent stopping power regardless of conditions. The 20-inch wheels make it compact for storage and transport, though they can mean a bumpier ride than larger wheels. Tubeless tires are a smart addition for fewer flats. The 3-year warranty really stands out, offering good peace of mind for an investment in a folding bike.
Pros & Cons
Pros
- Durable 4130 Cr-Mo steel frame
- Reliable 9-speed drivetrain
- Strong hydraulic disc brakes
- Compact folding design
- Tubeless tires for puncture resistance
Cons
- 20-inch wheel size
- No suspension for comfort
Specifications
- Handlebar Type Flat Bar
- Wheel Size 20 in
- Frame 4130 Cr-Mo Steel Frame with LUG Construction
- Item Length 150cm
- Number of Speeds 9 Speed
- Vintage No
Show all 35 specifications
- Department
- Unisex Adults
- Model Year
- 2026
- Cassette
- Lightweight 9-Speed 11-34T Cassette
- Unit Type
- Unit
- Manufacturer Warranty
- 3 Years
- Features
- Adjustable Seat, Lightweight, Quick-release seatpost clamp
- Shifter
- MicroShift Advent 1 X 9S
- Brakes
- Dual-Piston CNC Machined Aluminum Hydraulic Disc Brakes
- Folding Stem
- One-Piece Forged Aluminum Folding Stem
- Cable Housing
- LUG Housing
- Bike Type
- Folding Bike
- Tire Type
- Tubeless Tires
- Crankset
- Forged Aluminum Lightweight 44T Single Chainring
- Wheelset
- Aluminum Hub + Double-Wall Sleeve-Joint Aluminum Rim, 24 Spokes
- Brand
- ROCKBROS
- Custom-Built
- No
- Frame & Fork
- 4130 High-Strength Steel
- Brake System
- 160mm Front / 140mm Rear
- Brake Type
- Disc Brake - Hydraulic
- Suspension Type
- No Suspension
- Cockpit
- 6061-T6 Forged Handlebar & Seatpost
- Model
- ROCKBROS Gravis
- Shifter Style
- Trigger Shifter
- Drivetrain
- MicroSHIFT ADVENT 9-Speed
- Tires
- 406 x 1.95 inch CST Mountain Bike Tires
- Gear Change Mechanism
- Derailleur Gears
- Item Weight
- 11.8 kg
- Country of Origin
- China
- Frame Size
- 20 in
