Introducing the latest evolution of our unique MASON Definition, with configurable Campagnolo, SRAM and Shimano build options.

Already unique, the definitive sporty, all season, AllRoad Definition, has evolved further. Previously described as 'A masterclass in bike design and engineering' and 'Phenomenal' by road.cc, the latest version is even more refined, optimised and detailed for fast, variable surface speed and travel.

Shop Definition 3.0

Photographs captured during Josh Ibbett's Japanese Odyssey with the first Definition 3.0 Production Sample.

The Definition is mould-breaking. It is very hard to find a bicycle that competes with our MASON Definition on sporty, all-season, long-distance, AllRoad, practicality and performance.

The Definition shares the same overall geometry as our Columbus steel Resolution but is designed to have a sportier feel, whilst still retaining the engaging, long-distance comfort and dependability that MASON bicycles are renowned for. The premium Dedacciai aluminium frame is a super-efficient pedalling and power transmission machine. Low weight, custom shaped MASON x Dedacciai stays and large diameter down tube give it a punchy and responsive ride.

We have constantly updated, developed, and refined both the Resolution and Definition since their launch, but geometry and purpose stay unchanged. The Definition and Resolution started a new category and still remain in a class of their own.

This time around, the Definition has received some changes and new features to optimise and refine for the long-distance and All-Season riding that it already excels at. With our 'Ride Driven Design' mantra as a firm guideline, we have learned a great deal from our riders and customers since it's launch in 2015 and there have been many running changes, updates and new versions as our journey has progressed. 

Updates include:

- Revised hose and cable routing: As technology and components progress and evolve, we evolve too, but always following our 'Ride Driven Design' mantra. Modern electronic shifting and the increased use of 1x systems has allowed us to revise and clean up our cable and hose routing. For smoother runs and a cleaner aesthetic, all control cables and hoses now run through the down tube, via the special BB shell and out through the chainstays.

- We often fit modern dynamo lighting and charging systems to our builds, so for Definition3 we have added dedicated dynamo cable routing ports to the top tube, using the space freed up by refining the cable routing. This important revision means that the cable is more easily routed between front and rear lights and gives alternative mounting points, either at the seatclamp or dropout, depending on rack and bag setup and requirements.

- Optimised Seat Tube Sizing across range: Seat tubes on larger frames are oversize, to keep ride response and durability consistent throughout the size range and maximise power transfer for larger, more powerful riders. Lighter, smaller diameter, 27.2mm carbon seatposts on smaller sizes, add comfort for riders at the lower end of the height/weight range. 31.6mm carbon seatposts on larger sizes, add durability for taller, heavier riders whilst still helping to maintain comfort.

- Improved durability: Uprated tubing treatment and uprated accessory eyelets using 3M bonding plus compression fitting - for increased durability and resistance to harsh conditions.

- 8 frame size options are unusual for a small bicycle company like ours, but we believe that a large range of sizes helps to guarantee an optimised fit, essential for long-distance comfort and efficiency. 48cm through to 62cm, the geometry and clearances vary throughout the size range, meaning that there will be a Definition to fit you.

As always, we have been extremely careful not to 'mess with the formula' that made the original MASON Definition so magical, refined, dependable, engaging and confidence-inspiring... all year round. 

The geometry and clearances were right at the start and they are still right now, along with all the proper mounting points, so no changes there. The following changes changes and updates are designed to make your riding life even more practical, efficient and more fulfilling.

Shop Definition 3.0