New Second Generation Geometron G1: Even More Adjustable

The Geometron G1 (which Benji previously called ‘the best mountain bike I’ve ever ridden‘) is getting a makeover. The G1 is already a bike that through its ‘mutators’ can be set up in a range of guises for most purposes, and the new frame brings with it even more options so you can get your set up exactly right for your body size and ride style. Which might excuse the length of the press release (though perhaps not the quantity of adjectives) because it all takes a bit of explaining. Here’s the TLDR version for those with journo-length attention spans:

• New rear end for UDH compatibility and more range of adjustment
• The new rear end is retrofit-able to the current G1
• ZS56/ZS56 headtube to allow reach or head angle adjustments
• Size specific geometry
• Continuous seat tube profile for longer dropper options
• Still developed by nice people trying to do good things

The geometry numbers haven’t changed drastically, we have in essence honed them around the lessons we’ve learnt in setting up the old G1 frame and paid attention to areas that we had run out of range of adjustment in and optimised our base geometries around handling characteristics we have enjoyed.

Geometron

Have yourselves a closer look at the changes with this press release.

Introducing the all-new 2025 G1, born from the collaboration between Nicolai Bikes and Geometron Bikes. Five years since its initial release in 2019, the new G1 retains its trailblazing attributes, being one of the most adaptable and robust all-round mountain bike frames on the market. Built to withstand the punishing demands of aggressive riding year after year, the G1 offers a versatile platform that transcends conventional mountain bike categories. 

The G1 chassis stands as the cornerstone of revolutionary mountain bike geometry, redefining modern standards in mountain biking and setting the benchmark for performance and reliability: Ride with confidence and conquer any challenge. Developed continuously from the groundbreaking G16 in 2015, which diverted from conventional mountain bike geometries.The Geometron geometry numbers are not just arbitrary figures but the culmination of extensive research and rigorous testing. The result is ride characteristics that elevate both novice and seasoned riders to newfound levels of confidence, control and fun. The revolutionary geometry, adjustable frame concept and customisable build options conceived by Geometron cater to a wide range of riding styles and disciplines, from aggressive downhill shredding or party laps with your mates, to technical multi day trail riding and everything in between. The G1 has gained numerous accolades, from taking riders down their first black run at a bike park or first off piste trail at their local, taming the gnarliest world cup race courses, epic endurance challenges to podiums at multi day enduro races. The G1 offers a complete solution for riders seeking the ultimate mountain biking experience with maximum stoke at the end of each ride. 

An instrumental aspect of the new G1’s development has been incorporating invaluable feedback gathered from long-term internal and external test riders, and customers within the mountain bike community over the past five years. This collaborative approach with continuous commitment to development has driven refinements and enhancements to every aspect of the bike, ensuring that it not only meets, but exceeds the expectations of our dedicated community.

Crafted from premium materials and components, the G1 exemplifies uncompromising quality and reliability. From the meticulously handcrafted aluminium frame produced in Germany by Nicolai bikes, to the top-of-the-line bespoke suspension components fastidiously developed and manufactured in Italy by Extreme racing shox, every facet of the G1 is engineered to endure the rigours of the trail. The new G1 introduces several key changes aimed at elevating the riding experience.

Evolutionary Excellence: Introducing the new G1 – Redefining Versatility 

The new G1 epitomises the vision of a versatile, comfortable, and rugged mountain bike. Rather than slotting into a specific category, the G1 is designed to be the go-to option for riders seeking a single bike capable of conquering any off-road challenge. In its base configuration for enduro/aggressive trail riding or long days in the mountains the G1 has 162mm or 175mm Rear wheel travel (RWT) easily adjustable with two mounting positions in the shock lever that not only changes the RWT of the bike but also the linkage curve and in turn the suspension feel and attitude of the bike. One of the G1’s most underrated secrets is its exceptional pedalling performance. The bike’s suspension kinematics and optimised riding position work together to deliver a ride that’s both comfortable and remarkably efficient.

At the heart of the G1’s design philosophy lies its adjustability, empowering riders to fine-tune every aspect of their ride experience. Whether smashing technical descents or powering through demanding climbs, the G1 can be tailored to suit individual riding styles, strengths, and the unique terrain encountered. The key to the G1’s adaptability are the super easily changeable modular frame adjusters, aptly named Mutators located at the chain stay and seat stay. They allow for incremental changes to the head angle, bottom bracket height, chainstay length and most importantly to change wheel size. Independently isolating geometry changes without compromising other ride characteristics. This system enables riders to optimise weight distribution and handling characteristics according to their preferences and the demands of the trail. Geometron has curated a useful tool called the Mutation chart (available on their website) which shows the geometry of each frame size and the range of adjustment available, and what incremental changes can be made so that each rider can select their preferred configuration.

Further enhancing its versatility, adjustment range of the Mutators can now be used to allow the use of three different shock sizes. The factory setting comes with a 230x65mm shock which offers up to 175mm of travel at the rear wheel. For a XC/ Trail biassed setup, a 210x55mm shock can be used which delivers 155mm of travel – with a careful selection of light components this set-up can be the perfect companion for long epics on the trails. If your cup of tea is  party laps in the bike park or a DH race season, then the adjusters offer enough range to use a 250x75mm shock turning the bike into a downhill ready race rig with a maximum of 200mm of travel at the rear wheel.

In essence, the G1 puts the power in the hands of the rider allowing for precise tuning of every aspect of the bike’s performance. With a plethora of configuration choices, from the simplest adjustments to the most intricate setups, the possibilities are limitless. Making the right decision shouldn’t be daunting, whether you’re a fan of frequent tweaks or prefer carefully selected single configuration, rest assured that the Geometron team stands ready to provide expert guidance and support at every turn.

While the G1 name remains unchanged and our approach has proven itself, the year 2025 brings forth key updates.

Here is what’s new:

KEY CHANGE #1 – Size proportional geometry

One of the standout enhancements in the new G1 is the implementation of proportional frame sizing, a feature born out of extensive in-house testing, customer feedback and test rides conducted by Geometron in the UK. Recognising the need for riders of all sizes and genders to experience consistent ride quality, Geometron Bikes have meticulously crafted each frame size to ensure that every rider, whether 202cm or 160cm (6’8” or 5’3”), enjoys the same ride feel. The attention to proportional frame sizing not only enhances comfort and control but also underscores Geometron’s dedication to inclusivity and rider satisfaction.

KEY CHANGE #2 – Updated frame standards

With an eye towards innovation and compatibility, the new G1 introduces updates to accommodate the latest bicycle frame standards. This required a completely redesigned rear end which includes the innovative RADO (REAR ALIGNING DROPOUT). It has been redesigned to accommodate the SRAM UDH standard and also continues to allow  precise alignment during the assembly stage of the frame. The G1 ensures seamless compatibility with all drivetrain setups, offering riders increased flexibility and ease of maintenance. The frame is also thoughtfully designed to accommodate new generation single-crown, long-travel Enduro suspension forks with revisions to the geometry and fork size specifications. Now with its ZS56/ZS56 headtube, the G1 offers even more adjustment capabilities offering reach or head angle adjustments with optional headset cups. Riders who are between frame sizes can fine-tune their setup in the front triangle to perfectly match their individual preferences and riding styles.

KEY CHANGE #3 – Design language

The G1 showcases a fresh design language aimed at elevating both aesthetics and uncompromising performance. The most distinguishable feature of this update is the redesigned top tube, which not only enhances the bike’s sleek profile but also improves rider manoeuvrability on the trail. By lowering the top tube 25mm, riders are afforded greater freedom of movement, allowing for enhanced agility and control to set new PR’s on descents or click new levels of steeze in the air. Integrated seat tube and head tube gussets further reinforce the frame, increasing stiffness for a more responsive ride feel. Additionally, the seat tube features a continuous internal profile, allowing easy integration of long dropper posts. These refinements underscore Geometron’s commitment to pushing the boundaries of mountain bike design, marrying form and function seamlessly. 

Continued Collaborative Innovation:

Many of today’s complex technological challenges require a multidisciplinary approach. The G1 project combines the knowledge, expertise and skill sets of three independent and innovative European companies. Nicolai Bikes, Geometron Bikes, and EXTREME Racing Shox form a collaborative ecosystem with diverse perspectives and expertise: aluminium frame craftsmanship from Nicolai Bikes, advanced geometry, bicycle handling, and suspension kinematics knowledge from Geometron Bikes, and pioneering damper technologies from EXT Racing Shox come together with a shared a goal: to create a mountain bike that sets new benchmarks for performance, reliability, and rider enjoyment.

G1 – Engineering Features

Geometron Concept: Optimising Rider Position for Confidence and Control

In crafting the G1 series, our paramount consideration was achieving a rider-bike synergy that maximises confidence and control on the trail. To empower riders across all 5 frame sizes, we meticulously tuned the geometry to ensure consistent weight distribution through the contact patches. This involved maintaining a balanced front and rear centre ratio that scales uniformly across frame sizes as well as a balanced reach to stack ratio. As a result, whether on a small or XXL frame, riders can confidently initiate direction changes, navigate obstacles, and optimise braking traction without the need for exceptional flexibility or skill. Riders are able to maintain a comfortable consistent body position while maintaining load on the tyres and use the available amplitude of their joints to efficiently respond to the trail. While advanced suspension systems undoubtedly contribute to that ride quality, the rider’s space and relationship between the contact points are fundamental to handling and manoeuvrability.

With reach measurements ranging from 455mm on the small to the 535mm on the XXL, our design accommodates riders ranging from 202cm to 160cm (6’8” to 5’3”). Similarly, the rear centre length adapts accordingly to ensure consistent handling characteristics across the size spectrum. – ranging from 446mm on the small frame to 480mm on the XXL.

At Geometron we have extensive experience guiding riders of all sizes, riding styles and disciplines in selection of the perfect set-up. The G1 has the flexibility to customise rider setups, allowing for variations if required- a small frame paired with a 480mm chainstay length or an XXL frame with the shortest chainstay option. Ultimately, the Geometron Concept represents a holistic approach to mountain bike design, where rider comfort, control, and customization converge to elevate the trail riding experience for all.

Here’s what you can play with:

• 5 different front centre lengths.
• 6 different rear centre lengths achieved with chain stay mutators that are compatible with all of the 5 front centres.
• Wheel size options: full 29”, 29/27.5” or full 27.5”.
• Seat Stay Mutators- incremental BB height and head angle adjustments possible.

Frame details not to be overlooked:

• External brake hose and gear cable routing – robust and user friendly. 
• Threaded 73mm wide bottom bracket (BSA standard).
• Replaceable threaded inserts located throughout the frame for frame longevity.
• New two part chain stay protector with integrated cable routing and replaceable rubber strips.
• Straight seat tube for long dropper post insertion.

Rear wheel travel options:

• Base configuration:
  • 230x65mm shock – 162/175mm travel at the rear, 170/180mm travel at the front
• Short travel configuration:
  • 210x55mm shock – 142/155mm travel at the rear, 140/150mm travel at the front
• Long travel configuration:
  • 250x75mm shock – 182/200mm travel at the rear, 190/200mm travel at the front

Optimised 4 bar linkage system – The G1 key features:

• Progressive linkage design with a constant rate of change. 31% total increase in progression from its starting point in the travel at a ratio of 3.4. 

This means the force required to compress the suspension increases throughout the stroke more than just the spring rate alone, a constant rate change keeps things predictable. This characteristic provides a soft initial part of the stroke to improve sensitivity, gives the rider support when loading the bike dynamically or taking bigger impacts and gives sufficient mechanical resistance at the end of the stroke to reduce bottom out forces.

• Anti Squat value of 100% at 30% SAG, rider in the seated climbing position with a Center of Gravity (CoG) of 1180mm (size large frame) and 32/44T gearing. 

This provides a neutral pedalling behaviour which is efficient and neither constrains the suspension system to bob/squat or extend/block, improving traction and comfort on technical climbs.

• Anti Rise value of 62% at 30% SAG, rider in a descending position with a CoG at 950mm (lowered CoG) on a large frame. 

With consideration to mass transfer, this characteristic produces a Neutral braking behaviour for predictable ride feel when you hit the brakes.

Frame bearing and its protection concept selected based on load case and exposure to the environment

Full complement deep groove and angular contact ENDURO ball bearings are used throughout the G1’s frame. The bearings are protected within the frame with additional o-ring seals that are strategically placed in the bearing caps and bearing spacers. Combined with the bearings seals, this offers a quadruply sealed system and guarantees a long bearing life.

RADO 148×12

Adjustable, replaceable right-hand thru-axle mount for factory setting of exact toe and camber of the rear wheel. No crabbing here!

Extra Love

Choose your dream colour from an extensive palette of vibrant powder coats, sleek anodized finishes, or opt for the classic allure of a raw aluminium frame.

Add a personal touch with our Extra Love kit, featuring shock linkage, cable clamps, and bearing caps, available in eight striking colours.

Complete your custom build with our new Geometron decal kits. Crafted from a thick protective material, these decals not only shield your downtube but also come in a variety of colours, allowing you to perfectly match or contrast with your frame and Extra Love accents.

Materials

• 7020 T6 Aluminium main frame, swingarm and seat stays.
• Specific alloy selection for the bolt on parts based on load case and part design.
• High strength to weight ratio, durable, recyclable, hard wearing.

NICOLAI manufacturing

• 28 years of in-house experience in CNC machining, welding, powder coating and assembly

Production quality

• Made in Germany

Warranty and spare parts supply

• 5-year warranty covering breakages and material failure even in racing use – minimum 10-year spare parts supply

Bespoke EXT Storia V4 G1

At the heart of the G1 is the EXT V4 Damper, expertly tuned and perfected to seamlessly integrate with the G1 chassis & kinematic. The EXT suspension units are tuned with painstaking attention to detail, ensuring a ride quality that’s nothing short of extraordinary. Here are pre-release notes on the new Storia V4 damper that will be released alongside the G1 in June. The G1 V4 damper will retain the same Spherical eyelet bearings first seen in the G1 Storia V3, that remarkably improve suspension performance and reduce maintenance. Now with externally adjustable hydraulic bottom-out resistance, the Storia V4 boasts a new steel shaft with a DLC coating and a bladder-style IFP, reducing the reservoir size and improving frame clearance. Additionally, hidden inside, the shock has a new anti-topout device with a one-way valve that adds damper resistance during the last few millimetres of shock extension.

Deviating from this optimised setup on the G1 would be like missing a note in a symphony.

Build options:

Experience the thrill of building your dream ride with Geometron Bikes’ unique bike configurator and build process. Our approach puts the customer in the driver’s seat, allowing them to handpick every component of their bike to suit the individual’s style and preferences. We understand that every rider is unique, we believe in keeping things flexible. The listed stock builds serve as a blank canvas, ready for you to unleash your creativity. We know that the perfect fit and personal preferences are crucial for an unforgettable riding experience. That’s why we empower you to customise your final build kit. If you want to swap out the brakes for something more powerful? Upgrade the drivetrain for smoother shifting? With their flexible approach, the possibilities are endless.

Discover the joy of building your own masterpiece with Geometron Bikes. Your adventure begins here.

Beginning with tiered bundle packages- *Prices Inc. 20% VAT

Below, you’ll find our comprehensive base full build specifications and pricing. At the core of all Geometron full builds lies a diligently curated selection of components, chosen for their durability and performance and sourced from reputable manufacturers with whom we proudly collaborate. While the fundamental elements remain consistent across our build options, the key distinction lies in the drivetrain packages. Here are our two base build options:

Availability:

Geometron G1 will be available for direct purchase starting May 31st, 2024. Secure your new bike’s production slot now by reaching out to either of the dedicated teams below. For those in the UK and international enthusiasts seeking the unparalleled Geometron experience, please contact the Geometron team. For customers in Germany and Central Europe, we invite you to connect directly with Nicolai Bikes who are releasing their own Nicolai variant of the G1 for the European market in the near future. 

Hannah Dobson

Managing Editor

I came to Singletrack having decided there must be more to life than meetings. I like all bikes, but especially unusual ones. More than bikes, I like what bikes do. I think that they link people and places; that cycling creates a connection between us and our environment; bikes create communities; deliver freedom; bring joy; and improve fitness. They're environmentally friendly and create friendly environments. I try to write about all these things in the hope that others might discover the joy of bikes too.

More posts from Hannah