Independent editorial. Not affiliated with Brompton Bicycle Ltd.
The Brompton G-Line is Brompton’s all-road folding bike. It keeps the brand’s defining trick — folding small enough to carry indoors or onto a train — but adds larger wheels, wider tyres and a tougher build so it can handle gravel paths, broken tarmac and light trails that would punish a classic Brompton.
Short version: if you love the Brompton fold but ride rougher stuff than smooth city streets, and you’ll take the extra weight and bulk that buys you, the G-Line is your bike. I run one with a C-Line parked next to it, so most of what follows comes from living with both, not from a spec sheet.
Who the G-Line is for
- Commuters whose route includes towpaths, parks or rough roads.
- Travellers who want one bike that folds for trains and handles unpaved detours.
- Existing Brompton owners who find the 16-inch wheels harsh off smooth tarmac.
It’s not the bike if your priority is the smallest, lightest fold — that’s still the classic C-Line’s job, and I’ll tell you so even with both in my hallway.
G-Line vs C-Line at a glance
| Aspect | G-Line | C-Line (classic) |
|---|---|---|
| Wheel size | Larger (20”) | Compact (16”) |
| Tyres | Wider, all-road | Narrower, urban |
| Terrain | Mixed / light off-road | Smooth urban |
| Folded size | Larger | Smallest |
| Weight | Heavier | Lighter |
I’m keeping exact weights, gearing and prices out of here until I’ve checked them against Brompton myself — I won’t print a number I can’t stand behind. The specifications page has the structured table (same rule there).
What to check before buying
- Storage and carry. The folded G-Line is bigger than a classic Brompton. Measure where you’ll store it and how far you’ll carry it folded.
- Your real terrain. If 90% of your riding is smooth city streets, the C-Line may suit you better and fold smaller.
- Gearing for your hills. Confirm the gear range matches your climbs.
- Accessories that fit. Not all classic Brompton luggage fits the G-Line, so check before you carry one over — I’ve sorted what actually fits in the accessories comparisons.
Next steps
- Read the G-Line guides for setup, folding and maintenance.
- Check the full specifications.
- Compare accessories that actually fit.
Spotted an error or have first-hand G-Line experience? Get in touch.