British steel enduro bikes exude a charm all of their own. The Auckland Marra is no exception, and with its eye-catching rear triangle design, it takes technical fascination to a whole new level. There’s plenty to admire about this hand-built frame set from England. Here, we take a closer look at this exotic model from across the Channel.
The Auckland Marra in detail
- Area of use: Enduro
- Suspension travel: 170–200 mm
- Wheel size: Full 27.5” or Mullet (29”/27.5”)
- Weight: approx. 17 kg
- Price of frame set including shock absorber: 5,600 GBP
- Special features: Kolarp rear suspension system, adjustable geometry and kinematics, made in Britain, custom geometry and paint finish available
Handmade in England
Inspired by rides he’d taken with the legendary ultra-distance cyclist Mike Hall, Auckland Cycle Works founder Gary Ewing wanted to turn the established norms for mountain bike rear triangles on their head. Ewing didn’t design the first models using CAD software on his computer, but rather by building them out of Lego bricks.
Even the first rideable prototype bikes relied on unconventional systems. For the frame builder, there were virtually no limits. Old bikes were cut up and reassembled. His first designs were so creative that they earned him an Innovation Award at the prestigious Bespoked trade fair.
Like many other frame builders, Ewing had found the time during the Covid-19 pandemic to refine his flagship product, the Marra. Under the Auckland Cycle Works label, an iconic steel and engineering company from County Durham, founded in 1898, was revived in 2023. The workshop’s first custom bikes are now available to order.
Ewing also caters to individual customer requests. As production is carried out in small batches, quantities are limited. There are still a few places left for 2026. The frameset, including a Cane Creek Kitsuma G2 or RockShox Vivid Ultimate RC2T shock, costs 7,000 British pounds. For this price, customers can choose their preferred frame colour.
Chassis with a rear pivot point
In order to realise his vision of the perfect mountain bike rear triangle, Auckland-based inventor Ewing came up with some wild ideas. The first prototypes were still based on a concept adapted from the 1990s called the “Unified Rear Triangle” (URT), familiar from the classic Klein Mantra bike, which the developer reimagined for his own purposes.
However, Ewing soon abandoned this design and created a new system, which he named “Kolarp Suspension” and had patented. The key feature of the high-pivot rear triangle, with its virtual pivot point and rearward-facing wheel travel curve, is that the chain guide is suspended not from the frame but from the lower rocker arm of the Auckland Marra. The I-Track pulley keeps the chain taut without the rear derailleur moving too much. To adjust the kinematics, the front shock mount can be adjusted in two-millimetre increments.
According to Ewing, the rear suspension performance of a modern full-suspension mountain bike deteriorates by 28 to 38 per cent during hard braking manoeuvres. By contrast, the impact of braking on the suspension of the Auckland Marra, which features the Kolarp Suspension System, is said to be just five per cent, which is claimed to improve its performance in such situations by 34 to 50 per cent.
The British rider’s enduro bike thus promises to extract more potential from the high-pivot rear triangle and significantly improve braking performance. Furthermore, the changes to the geometry caused by suspension movement are designed to remain consistently minimal in various riding situations, whilst optimised suspension stiffness is intended to enable the bike to climb more effectively in all gears.
Steel is real
In true British style, the Auckland Marra’s frame is crafted from high-quality Reynolds 853 steel. Frame builder Ewing works closely with the experts at Reynolds to provide the enduro bike with a bespoke set of tubes.
Another characteristic feature of the island’s mechanical engineering is that the bearings are designed to be particularly well-sealed, generously sized and durable. Naturally, the bottom bracket is fitted in accordance with the BSA standard.
The Auckland is only approved for 27.5-inch rear wheels. At the front, you can choose between 27.5-inch and 29-inch wheels. The frame is compatible with suspension forks offering 170 to 200 millimetres of travel.
For his personal show bike, Ewings has opted for a 180-millimetre fork with a 63.25-degree rake. The straight seat tube is 430 millimetres long in frame size L, yet still allows for a long seatpost insertion depth.
The seat angle measures 76.5 degrees, whilst the reach is 485 millimetres. A modular dropout design allows the chainstays to be adjusted by a total of twelve millimetres. In the neutral position, the chainstay length is a compact 429 millimetres.
Conclusion
Auckland Cycle Works’ short history is already steeped in heritage. The Marra is a unique steel full-suspension bike with British charm. It’s not a bike for everyone, but rather a custom project created with a great deal of passion, and one that has a story to tell. And isn’t that what our favourite hobby is all about? In any case, I find the Auckland Marra far more exciting than any off-the-shelf bike. - Jan Timmermann, BIKE editor
Jan Timmermann
Editor