Brompton M6L Review

Brompton M6L: the benchmark for compact folding

The Brompton M6L (now part of the C Line range) represents what many consider the gold standard for compact folding bikes. This review examines whether the reputation is deserved and who the bike actually suits.

Key specifications

  • Wheel size: 16 inches
  • Gearing: 6-speed (2-speed hub plus 3-speed derailleur)
  • Weight: Approximately 11.6kg (steel)
  • Folded size: 585 x 565 x 270mm
  • Handlebar style: M (mid-height)
  • Mudguards: Included
  • Rack: Not included (L denotes no rack)

Folding and unfolding

The Brompton fold takes around 15-20 seconds once practised. The three-step process becomes muscle memory quickly: fold the rear wheel under, swing the front wheel back, and drop the handlebars. The bike stands stable when folded without a kickstand.

The folded package is remarkably compact. It fits under train seats, in overhead luggage racks, and in small cupboards. Few competitors match this size.

Ride quality

Small wheels mean a different feel from full-size bikes. The M6L accelerates quickly from stops and handles nimbly in traffic. The trade-off is sensitivity to road imperfections: bumps transmit more than with larger wheels.

The 6-speed gearing handles moderate hills well. The range suits urban riding and gentle gradients. Steep or extended climbs may require lower gearing, available on the 12-speed P Line.

For typical UK commutes on reasonably maintained roads, the ride is entirely practical. It is not a leisure touring bike, but it is not meant to be.

Build quality and durability

Brompton's London manufacturing and quality control produce consistently well-built bikes. Frames rarely fail. Components are standard where possible, simplifying maintenance. The brand's dealer network means service is widely available.

Second-hand Bromptons retain value well, often selling for 60-80% of new price after years of use.

Who should consider the M6L

The M6L suits:

  • Train commuters who need the most compact fold
  • Flat or apartment dwellers with minimal storage
  • Riders making multi-modal journeys (bike plus bus, train, taxi)
  • Those prioritising build quality and long-term reliability

Consider alternatives if:

  • Budget is limited (see budget options)
  • You prioritise ride comfort over compact fold (see Tern or 20-inch folders)
  • Your commute involves significant hills (consider the 12-speed P Line)

Verdict

The Brompton M6L earns its reputation. The compact fold is unmatched, build quality is excellent, and the bike handles daily commuting reliably. The price is high, but the bike holds value and lasts.

For train commuters and city dwellers, it remains the default recommendation. For other use cases, alternatives may offer better value.

Compare with: Brompton vs Tern | Brompton vs Dahon