Curve Cycling
GMX+ Steel Frameset
GMX+ Steel Frameset
Customers outside Australia & European Union may be charged import fees (duties, taxes, etc) by local customs authorities upon delivery. Please see our shipping policy for more information.
.
Couldn't load pickup availability
Enquire
Enquire
For info on availability, please contact sales@curvecycling.com,
call us on 03 9088 0274.
Alternatively, Enquire Now.
Geometry
Geometry
You can find geometry charts for all our current frame models HERE.
Tech Info
Tech Info
- Headset Specs
- Headset Assembly & Service - IS42/52 | ZS44/EC44 | ZS44/ZS56
- Frame Specs
Shipping
Shipping
Free International Shipping for all Framesets, Complete Bikes, Forks, Wheelsets, Bars and Rocket Pooches is included in the sales price (*excludes Belgie DISC Ultegra)
All other products are subject to shipping charges calculated at checkout. See our Shipping Policy for further details.
FAQs
FAQs
Check HERE for further info regarding custom paint, bike set up and more.
| I want to attach bags. What will it do to the frame finish? |
Curve's steel frames are finished with high-quality and durable paint, but the paint is not unaffected by rubbing from bike bags or rock strikes etc. If you want to keep your paint looking pristine, we recommend that you use some kind of protective film - especially in the high-wear areas where bag straps are in direct contact with the frame. Stock Ti frames are not painted, but bag rub will affect the surface finish. The lighter, brushed, finish can be refreshed using a fine abrasive pad, but the darker blasted finish can only be refinished by media blasting. To keep your Ti frame looking pristine, we recommend using protective film. |
| I want to get a custom frame bag made. Can you give me the frame dimensions? | Of course! Have a look at our bagmaker page HERE where you can download full-scale PDFs showing the internal dimensions of all our frame models. |
| I want to use a rack. Is the frame compatible? | Yes, with a Relaxle you can use a rack on most frames regardless of whether they have integrated rack mounts or not. Some of our frames do not have upper attachment points on the seatstays (such as the Belgie range and AIR Kev for example), to get around this, you can use a seat clamp with built-in rack mounts. |
| How much weight can I carry on a rack? | The maximum weight when using the seatstay/chainstay M5 mounts should not exceed 20kg. Check the tightness of the bolts regularly! Note: This rating is for smooth roads & gravel. For anything rougher, the weight limit decreases. Use careful discretion when gauging how much weight to carry on rough gravel or off-road adventures. |
Built on the success of its titanium GMX+ cousin, Curve is proud to present the GMX+ Steel. After three years of development and testing, Curve's steel bikepacking bike is finally available in two colourways.
Introducing the Curve GMX+ Steel in vibrant Roadhouse Pink. This iconic colourway pays homage to the sun-faded pink paint of the legendary Pink Roadhouse in Oodnadatta. It's a hue that captures the spirit of the outback, where the scorching sun leaves its mark on everything it touches. Alternatively, the Nitro Chocolate colourway is a mesmerising fusion of rich chocolate brown with a subtle sparkle that evokes the enchanting play of moonlight on a remote Gibber Plain. It's like having a taste of Outback Australia's magic with you as you ride.
The GMX+ is inspired by the intrepid Overlanders of the 1890s, who covered incredible distances across the harsh, barren Australian outback without support. The GMX+ is a modern adventure bike designed with wide tyre clearance thanks to our innovative carbon fork, ultra-wide drop bars for stability, numerous mounting points and generous amounts of room for carrying water or other gear.
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. It's our very own reimagination of a bikepacking bike. In recent years, the GMX+ has taken on some of the most challenging races worldwide, including the Tour Divide, Silk Road Mountain Race, and Race to the Rock.
Load Up
The GMX+ Steel lets you carry more water and pack more gear. The steel frame includes mounting points on the rear stays and offset mounts on the downtube, allowing riders to run a full-size frame bag plus 1 litre bottles to either side. The Seek 430 FM fork has 4 x M5 heavily reinforced mounting points on each side, with a recommended maximum load capacity of 7 kilograms across three mount points (on each side). You read this correctly - it's a carbon fork able to carry a remarkable 14 kilograms of load safely!
Class Leading Carbon Fork
Our Seek 430 FM fork has been made to work in unison with our GMX+ (Ti & Steel) framesets and our popular Walmer Bar and Remlaw Bar. It improves on the original Seek 430 fork with updated brake hose and dynamo cable routing, the introduction of flat mount brakes and the addition of four heavily reinforced M5 mounting points per fork blade that can carry up to a whopping 7 kg each (maximum) when secured across three mounts! That's a total of 14 kg that can be safely carried on the Seek 430 FM! To achieve this, we left the industry-standard rivnuts behind and instead developed our own unique thru-mounts, completely re-thinking the way the mounts are added to the fork blade.
Drop Bar, Flat Bar or Riser Bar?
The GMX+ Steel can accommodate a drop bar or flat bar. Any wide drop bar, especially our Walmer Bar, will work with a shorter stem, as will our unique Remlaw Bar. Other flat bar designs will also work well but may require a longer stem. Due to the low front end on the GMX+ Steel, which isn't corrected for suspension, an even more relaxed touring position is possible with a high-rise flat bar.
Frame Sizing
The GMX+ Steel ranges from size XS to XL with clearance for up to 3" tyres. Sizes SM–XL are designed for 29" wheels. 27.5" wheels are required for size XS to ensure optimal performance. For more information on the GMX+ geometry click HERE!
Want to Carry More?
*There is ample room for bikepacking bags on all frameset sizes. To make sure current, prospective or custom bagging fits your frame size, please see our Bagmaker Drawing page.
Frameset
| Frame: |
- Columbus Cromor & 4130 chromoly |
| Seek 430 FM Fork: |
- Carbon construction |
| Curve Headset: |
- 44/56 mm zero-stack |
| Other: |
- Curve 29.8 mm Black Alloy seat clamp |
FAQs
| The reach on the geo chart looks long. What size is good for me? |
The short answer is that the reach number may be somewhat deceiving as the frame is designed to be run with a shorter stem. That, in combination with the comparatively steep seat angle, reduces the effective reach of the frame. Please reach out to sales@curvecycling.com if you have any questions about sizing. Read more about the GMX+ geometry here: GMX+ Geo Blog |
| Why flat mount? |
There are very few drop-bar groupsets available with post mount calipers, so we decided to introduce flat mount on GMX+ Steel to make the groupset selection for drop bar setups easier. |
| What are those black brackets on the downtube for? |
In order to reduce the number of holes and M5 mounts added to the downtube, and to add stability to the offset mounts, we decided to make these offset mount support guides specifically for the GMX+ Steel. These guides must be used when attaching bottle cages to the offset mounts. |
| What are the extra plates with three holes I got with my SM or XS frame? |
These are adapter brackets for the rear M5 mounts so you can attach a regular bottle cage to the back of the chainstays and seatstays. The plate is not needed for sizes MD and up. |
If you are building your Curve frameset with a self-supplied groupset, please see the specification guide via the link below to ensure the necessary parts are sufficiently compatible with our framesets.
The specification details may change over time. Please check HERE for the latest version.
Collapsible content
Frameset Specifications for Self-Supplied Groupsets
Customer Reviews
My steel GMX+ arrived two days before a trip that included carrying climbing gear and all other necessities for 800 miles. Set up was a breeze, Curve was thorough and thoughtful every step of the way.
This bike quickly planted itself at the top of my list of all time favorites. It's fast as hell, stable as a sure footed mule on the chunkiest of terrain, and fun going up, down or across. My bike was loaded pretty heavy and it never felt like I was near the max of what it could handle.
I got a size small and bumped my bar size up to a 55cm. Perfect fit. Riding in the drops is stable and fun. I often found myself bombing sections of the tour divide as if I was on my hard tail
Compared to other steel bikepacking rigs I have owned it is wildly light. I got the carbon Dirt Hoop upgrade. Someday I'll go to the carbon walmer as well.
No complaints. All around I am smitten with this machine, it made me wish I could disappear for years on end, instead of the weeks I had.
Just completed South Australia’s off road Mawson Trail (starting Adelaide), approx. 850km on a steel GMX+ (wireless X01 derailleur) purchased ~Sep-23 from Omafiets, Sydney.
Bike serviced pre-ride at Cyclemax Crows Nest with extra sealant.
Bike was flawless over the Trail, no mechanicals or punctures.
Walmer bars and Mezcal tyres helped out over the many descents and probably saved the day during the last descent into Mt Little Station (you’ll know the one).
Gearing was spot on, rode many climbs that others walked (e.g. day 1 Batchelor Rd). One click down/upshift of three gears brilliant for the many creek crossings in the Flinders Ranges.
All terrain handled: deep sand and gravel; fist sized rocks and babies heads; excelled on Corrugation Road Hell approaching Rawnsley Park Station.
The GMX+ is an imposing bike and can seem overbuilt - until it rides over everything with confidence and predictability, while loaded like a donkey.
Bike as stock except swapping the saddle for a Selle San Marco Shortfit 2.0 Supercomfort Racing saddle and DMR Vault pedals.
Additions: Tailfin alloy rack (thru axle 1.5mm pitch) + AP20 trunk bag; Tailfin 1.5L top tube pack; two Tailfin large Cargo Cages; Frameworks Design half frame bag (70mm width); 4L CrankTank; two Sea to Summit Big River 20L dry bags; Arundel steel bottle cages; four Bike Bag Dude feed bags; Apidura Backcountry Down Tube 1.8L pack; Sinewave Revolution USB Charger; Busch & Muller Secular Plus rear light; Schmidt SON Edelux II front light; Shutter Precision/SP Dynamo Connector.
Tip: get the MT app for info on each section and the current hazards, e.g. to avoid the prickles around Jamestown.
Used David Hume’s GPX file for Garmin which is 98% accurate. MT trail markers do exist.
Sexy beast
- Choosing a selection results in a full page refresh.
- Opens in a new window.