Single-chainring (1x) gearing has become the go-to for adventure and gravel bikes, borrowing the best ideas from mountain bike and road tech. Here's why one-by works so well off-road, and how Shimano's GRX groupsets — the ones we build with — compare.
Why ride 1x on gravel?
With one chainring there's no front derailleur to think about: a simpler drivetrain, fewer gears to manage mid-trail, and a more consistent chainline. That means better power transfer, less drivetrain wear, and a smoother, quieter ride — exactly what you want when the surface is doing its best to distract you.
The GRX range explained
Shimano and SRAM both make gravel-specific groupsets; at Pearson we favour Shimano for its quality, functionality and dependable supply. The GRX line-up maps neatly onto Shimano's road hierarchy:
- GRX 600 — the affordable option with a strong balance of performance and price. Road equivalent: 105.
- GRX 800 — lighter, with Hollowtech II crank arms and a more durable cassette. Road equivalent: Ultegra.
- GRX 815 Di2 — GRX 800 quality with electronic shifting: precise, programmable, and customisable to your preferences.
How 1x keeps the chain on
The classic worry with one-by is dropping the chain on rough ground. GRX answers it twice over: a Dynamic Chain Engagement tooth profile — alternating thick-and-thin teeth shaped to grip the chain — and a clutch rear derailleur that tames chain slap for a quieter ride and a protected frame.
Gearing for the steep stuff
A typical setup pairs a 40 or 42-tooth chainring with a wide 11-42 cassette — enough range to winch up steep, technical climbs while still giving you something to push on the flat.
Ride it on the On & On
Our gravel range runs the full GRX spectrum, from the GRX 610 through to the GRX 815 Di2. Not sure which suits your riding? Talk to the team — we'll never spec you more than you need.
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