The Ultimate Adventure Bike

The Curve GMX+ is inspired by the intrepid Overlanders of the 1890s, who covered incredible distances without support across the harsh Australian outback. Curve have designed a bike that can do the same, but with much more ease using today’s modern technology. The Curve GMX+ is an adventure bike designed with wider tyre clearance thanks to Curve’s innovative carbon fork, ultra-wide drop bars for stability, and numerous mounting points for storage or water.

Tested in real-life conditions, the original GMX was designed for Race to the Rock, a harsh, remote desert race in Australia. With testing came improvements to the bike geometry and fork clearance, and so the GMX+ was born. In recent years, the GMX+ has taken on some of the most challenging races worldwide, including Tour Divide, Silk Road Mountain Race, and Race to the Rock.

Curve GMX+ V2 Frameset

The new ‘V2’ GMX+ is still unmistakably a GMX+. It has just been improved in the right places. Still ready to take on multi-week tours through challenging terrain, and carry the water, food and gear to stay safe out there. Still a long, stable bike for rough roads, corrugations, desert sand and river stones. The idea hasn’t changed – just the execution:

• The geometry has been relaxed, with a longer head tube, especially in the larger sizes. At the small end, standover has come down a touch. The targeted geometry tweaks to match how riders have used this style of bike over the years, without noticeably compromising its load-carrying capacity or handling.
• The GMX+ V2 is now optimised around 2.6” tyres. That is what most GMX+ riders are actually using, and it also lines up nicely with wide-tyre availability right now. There is still room for 3.0” tyres for loaded missions on sandy desert roads when you need them.
• A new dropout system introduces the widest range of drivetrain flexibility possible. The GMX+ V2 uses the a sliding dropout mechanism with a wide range of insert options. The stock setup is SRAM UDH, but the frame can be configured for a huge range of combinations across axle spacing, brake mount type, axle type and drivetrain. That includes Rohloff, SRAM T-type, UDH, and hangerless single speed.
• The seat-stays are also more minimal, adding a touch more comfort
• The GMX+ V2 features more bosses, including top tube ‘bento box’ style mounts and new angled seat stay cargo mounts.

The GMX+ lets you carry more water or load more gear. The titanium frame includes mounting points on all rear stays and offset on the downtube, allowing riders to run a full-size frame bag plus 1 litre bottles to either side.

The new Seek 430 Flat Mount fork has 4 x M5 mounting points on each side, with a hugely increased load capacity of 7 kilograms each side, when attached via three mount points. To achieve this, Curve completely re-designed the way the mounts are added to the fork blade. They left the industry-standard rivnuts behind and instead developed their own unique thru-mounts made from 6061-T6 alloy. The mounts are supported by both sides of each fork blade, and they have a larger surface area – this results in a stronger, more durable mounting interface.

The Curve Walmer Bar is the perfect companion to the GMX+, as it was originally designed to work together with the GMX+ frame and Curve’s non-suspension-corrected SEEK 430 fork as an Off-Road touring system. This flared drop bar is available in several sizes and will provide the rider with more stability, hand positions, and storage space than other available handlebars.

Drop Bar or Flat Bar? Although conceived originally as a drop bar rig, the GMX+ can accommodate a drop bar or flat bar. Any wide drop bar, especially the Walmer Bar, will work with a shorter stem, as will Curve’s unique Remlaw Bar. Other flat bar designs may also work well, but a longer stem length may be needed.

A few words about the unique geometry of the GMX+. Over the last five years, the GMX+ geometry has been tested, refined and proven over thousands of kilometres of bike-packing racing and touring in remote areas around the world. The GMX+ is a big bike. It’s a long bike. But there are very good reasons for this. A long wheelbase is beneficial for control over rough terrain, and it also results in a super stable platform for both climbing and high-speed descending especially when carrying a substantial load.

The GMX+ is designed to be paired with a short stem and handlebars such as the Curve Walmer Bar, which has some back sweep. Both serve to shorten the effective reach. As an example, for a complete XL GMX+ (or XXL in titanium), we would recommend nothing longer than a 60 mm stem – going shorter is totally fine, too. Another element to consider when investigating reach is seat tube angle. The steep seat tube angle on the GMX+ moves the riding position forward, more forward than many bikes in its category, again reducing the effective reach – Curve have found this position beneficial for endurance riding in their many years of field testing.

The GMX+ stance is longer and lower than most bikes in its segment but this uniquely allows it to be set up in a number of modes – a drop bar or flat bar setup which is reasonably low, or a more relaxed and upright set up with a riser bar, without getting too high. Curve have also deliberately designed the GMX+ with a high stand-over to maximise frame bag and water-carrying space, critical for touring in more remote places. A large central triangle is important for maximising load-carrying capacity.