Press & Reviews
Press
Cycling Weekly | ISO2
The ISO is a bike built with a specific purpose in mind - exploration. If you were heading off into the unknown you’ll want a bike like this beneath you. Rugged, comfortable and sure-footed with the option for carrying as much kit as you’re going to need.
Overall 4.5/5
Cyclingworld Europe Awards 2025 | ISO2
Silver Award for our improved go-anywhere drop-bar legend
Best Gravel Bike Silver Award
Gravel and Adventure Bike Of The Year 2019/20 | InSearchOf | road.cc
Mason ISO: "It’s an uncompromising machine and one we think is utterly worth it. A bike that makes you want to get out and ride sounds like it has priceless qualities and more than worthy to be our Gravel and Adventure Bike of the Year in 2019."
Overall 5/5
5/5 | Offroad.cc | InSearchOf Force 1X
Redefines what a drop bar bike is supposed to be capable of.
Overall 5/5
10/10 | CyclingWeekly | InSearchOf Force 1X
"...it lets you go further and more extreme than just about any other drop bar bike."
Overall 10/10
Fiets Magazine | InSearchOf | Grouptest WINNER
The ISO is made for much more than 'normal' gravel and fast stretches of strade bianche looking roads. It's an adventurebike made to do whatever you want.
Group Test Winner
MasonCite
Christian Berthold - ISO
It is amazing and supersedes my expectations
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I have built up the ISO and have now ridden with it on different terrains – it is amazing and supersedes my expectations. I have built the wheels myself with a SON dynamo hub – the dynamo cable routing is elegant due to the nice frame and fork design.
The ability to fit large tires really makes a difference on trails (I equipped it with 27.5 x 2.8 ones). With this setup riding a technical trail really makes for fun – and even on wet and slippery roots the ISO feels safe.
I use a mullet setup with a GX derailleur and a modified Rival lever for the correct cable pull ratio. Thus, very steep (20%) roads/gravel/trails are very doable. On normal gravel roads the ISO feels comfortable but due to the drops faster riding is also possible and fun. Finally, in combination with Hope RX4+ brake callipers, braking feels very smooth and precise.