Mason Cycles’ road & gravel bikes keep evolving with larger tires, modern geometry & more hauling capacity to extend their adventure capabilities. Now the new ISO takes #AdventureSport riding further afield In Search Of even more off-road trails to explore with dropbars, 29er or 27.5+ wheels, and some trick detailing…
Mason Cycles ISO 29/27.5+ steel bikepacking mountain bike
Mason Cycles started out developing the Definition and Resolution disc brake road bikes with larger tires to open up more places to ride year round. That quickly evolved into the 650B Bokehs for gravel adventures. And now the new ISO expands adventure trail riding even further off-road. The new ISO is an even more progressive bike for Mason, with a new Dedacciai steel frame and carbon fork design that can fit wide 29er tires or even full plus-sized 27.5 tires to take on ever steeper & rougher terrain on bikepacking adventures far from tarmac. beyond just adding a lot of mounting points for accessories, Mason added a few extra tricks including a unique lightweight, load-bearing front fender that will make taking loaded bags much more secure off-road.
Mason ISO bikepacking bike Tech Details
The new Mason ISO is built from a custom-shaped & butted Dedacciai Zero steel tubeset developed for Mason, plus a mix of a Reynolds 853 seattube, a stainless bottom bracket, and UK-made Mason x Bear flat mount dropouts. This unique tubing design & spec is really one of the key places where Dom Mason’s years of frame shines, setting his bikes apart.
The bike gets triple Anything cage mounts on both top & bottom of the downtube, plus forward-facing on both fork legs, in addition to standard seattube bottle bosses. Both frame and fork also get braze-on mounts for both full coverage fenders and front & rear racks.
The Boost-spaced frame uses an integrated headset for the 1.5″ tapered steerer fork. That new carbon Hot Shoe fork is suspension corrected for a 100mm travel fork (if you decide to go that way) and gets internal routing for a dynamo for extended off-road touring.
Strapped onto the Hot Shoe fork is the unique new Shutter Mudguard, an integrated fender that can support 500g of load and includes lash down loops.
The ISO routes the rear derailleur and brake internally (or internal Di2), and includes mixed internal/external routing to run a stealth dropper seatpost. The bike is optimized for 1x drivetrains, but it can be configured with a band clamp front derailleur too. The bike gets a threaded 73mm BSA bottom bracket and uses a 31.6mm seatpost.
The ISO is designed to fit up to 29 x 2.4″ or 27.5 x 2.8″ tires. A medium sized ISO (50cm) has a claimed weight of 2400g complete with its axle, derailleur hanger, and all bolts & cable ports. The ISO comes in a wide size range and in two colors – gray or green.
Mason ISO bikepacking bike Availability, Spec & Pricing
The new Mason ISO will be available either alone as a frameset for £1495, or in one of two complete bike builds. A SRAM Force 1x Hydro complete bike will sell for £3500 and a Rival 1x Hydro complete will sell for £3195.
Both complete bikes share a Truvativ Stylo DUB crankset with a 34T chainring, Ritchey VentureMax Flare bars & stem, Mason seatpost, a Fabric Scoop saddle and either a new Mason x Hunt ‘The Search’ 29er wheelset with a dynamo of Hunt’s 27.5 TrailWide wheels wrapped in either WTB Ranger 29 X 2.4″ or 27.5 x 2.8″ tires.
