Mason unveils Definition 3.0: new features sit alongside time-proven geometry on updated all-season bike

Mason has launched the Definition 3.0, its long-distance all-road bike that we first saw a few weeks ago when Transcontinental Race winner Josh Ibbett rode it in the 2,700km Japanese Odyssey endurance cycling event. At the time, we had the pictures but Mason was keeping shtum about the update. That has all changed with the official unveiling. 

We’ve been huge fans of the Mason Definition since its launch in 2015. Back then, we described it as “a four-season long-distance machine with the manners of a tourer and the temperament of a race bike”, and that pretty much sums it up.

The Definition shares a geometry with the Mason’s Resolution, made from Columbus steel, but it’s designed to offer a sportier feel while retaining long-distance comfort.

> Read our review of the Mason Resolution Force AXS

It’s built from Dedacciai aluminium alloy tubes with Mason’s customary attention to detail. If you ever chat with brand founder Dom Mason, you’ll soon recognise that he’s definitely the sort of bloke who sweats the small stuff. He’s meticulous-going-on-obsessive about the minutiae of bike design.

What has always set the Definition apart, though, is the ride quality. The Definition rides beautifully with sublime handling. 

When we last reviewed a Mason Definition in 2022, reviewer Stu Kerton said, “The way this thing rides is a masterclass in bike design and engineering.”

Mason has updated the Definition for 2024.

“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,” says Mason. “With our ‘Ride Driven Design’ mantra as a firm guideline, we have learned a great deal from our riders and customers since its launch in 2015 and there have been many running changes, updates and new versions as our journey has progressed.”

So what has changed? Well, first, we’ll tell you what hasn’t. The geometry remains the same as ever, and that’s a good thing because it allows you to ride all day in comfort. If you want to put some figures on it, the 56cm frameset comes with a 560mm seat tube (centre of bottom bracket to top of seat tube), a 561.1mm effective top tube, and a 170mm head tube. 

In our 2022 review we said, “The geometry is spot on, with a balance of angles and tube lengths that sits towards the endurance end of the market. The front end isn't as razor-sharp as the raciest of race bikes, but it’s very close, and the slightly slacker head angle – plus a wheelbase a few millimetres longer to accept full mudguards – means handling that's a little bit less frantic. It really allows you to ride the Mason quickly over long distances.”

That’s the whole idea of this bike. The Definition comes in eight different sizes from 48cm up to 62cm, catering to the vast majority of riders out there.

Mason hasn’t messed with the clearances on the Definition 3.0 either. You can still fit 32mm tyres with mudguards and 35mm without, so there’s plenty of practicality here. 

What has changed is the brake hose and gear cable routing. Mason says that the popularity of electronic shifting and the increased use of 1x [single chainring] systems has allowed it clean things up. All cables and hoses now run through the down tube and out through the chain stays via a special bottom bracket shell.

Mason uses the space freed up by the new cable routing to add dedicated dynamo cable routing ports to the top tube for those who want dynamo lighting and charging.

“This important revision means that the cable is more easily routed between front and rear lights and gives alternative mounting points, either at the seat clamp or dropout, depending on rack and bag setup and requirements,” Mason says.

Larger frame sizes now come with oversized seat tubes “to keep ride response and durability consistent throughout the size range and maximise power transfer for larger, more powerful riders”. 

Smaller frame sizes get a 27.2mm carbon seatpost that’s designed to add comfort for riders at the lower end of the height/weight range. On the other hand, taller and generally heavier riders now get a 31.6mm diameter seatpost.

Something that you might not notice is that Mason has also worked on improving longevity. 

“Improved durability is achieved through uprated tubing treatment and accessory eyelets, ensuring resistance to harsh conditions,” says Mason.

There are new colours too, Mason having transferred SensorBlue (main pic) over from elsewhere in its range and introduced a new metallic ShutterBlack finish (above). The existing Vela option (below) remains.

The Definition is available in Shimano, SRAM, and Campagnolo builds.

Has the old Definition magic been retained? Luckily, we won’t have to wait too long to find out because our tech writer Suvi Loponen has been riding the new model for the past couple of weeks. Stay tuned for a review on road.cc soon.

Get more info from masoncycles.cc.

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