Bokeh Ti Ultegra Di2 Hydro £6,145.00

InBoard Disc-Mount

The calliper is mounted on the chain stay, this allows us to use lighter more comfortable seat-stays and gives a flex free mounting for the post-mount components to be welded to. Mounting the brake on the chain stay also keeps it cleanly out of the way of rack and ‘guard stays.

Multiport

Our frames use an adaptable, internal cable routing system. Developed by us to allow your Mason frame to be used with a combination of control systems and adapt and evolve with your requirements and riding styles. We were the first to bring this type of system to a performance steel frame and now use this system across our range. Interchangeable alloy parts allow five options:

1. Full cable outer. 2. Hydraulic Hose. 3. Split outer. 4. Electronic cable [e.g. Shimano Di2]. 5. 2 x Hose/cable or Hose/Dynamo wire 6. Blank.

Taper Head Tubes

Our frames use modern 1-1/8” - 1.5” taper head tubes. Pioneered by composite frames, the taper head tube makes huge sense for metal frames too;

The large overall diameter provides a useful weld area. The fully integrated headset is light and has a very low stack-height. Large 1.5” lower bearing, mated to a tapered carbon fork steerer, spreads the load and gives flex-free braking and instant response to steering input.

Threaded Bottom Brackets

We choose a more traditional 68mm BSA, and T47 threaded standard for our frames because we know that it gives greater durability and creak-free reliability over many miles. The threaded BB is easier to service using standard tools and you are more likely to find a replacement when adventuring far from home. A properly lubricated, threaded BB is also an ideal interface with a metal BB shell.

BoatTail Stays

Unique to MASON. The seat stays flow out of the ovalised top tube and then curve and taper down to meet the chain stays which curve up towards the axle. We call this ‘BoatTail’, a custom bend giving disc-rotor and calliper clearance, helping to avoid chain-slap on the rough stuff and allowing a little compliance to help smooth the ride.

F-Stop Axle System

Internal Routing

We route the hoses and cables internally where practical, keeping the 'adventure nature' of our bicycles firmly in mind. For smoother runs and a cleaner aesthetic, all control cables, hoses and electronic shift control wires now run through the down tube, via the special BB shell and out through the chainstays, guided by our Mason 'MultiPort' adaptable inserts. Interchangeable Internal routing keeps the control cabling away from road dirt and grime, helps avoid accidental damage, makes cleaning easy, de-clutters your bike and means you can adapt your bike easily to work with various shifting and braking methods. For adventure and endurance riding, internal routing also has the advantage that it is easy to strap frame packs to the frame tubes without being hindered by external cabling and hoses.

Integrated Headset

Integrated, 41.8ø upper, 51.8ø lower, for taper head tube. Both bearings are ‘ACB’, meaning ‘Angular Contact Bearings’. The head-tube seat angle is 45º.

The headset drops into a tapered seat in the head tube and is tensioned using a headset tensioner within the fork steerer. Tensioning the headset centres it on the taper and prevents any play. The larger lower bearing allows a tapered steerer and larger crown. This gives sharper response, helps reduce flex under braking and spreads bearing load.

650B/700C

The Bokeh and Exposure are optimised for large-volume treaded tyres, and are designed for 650B and 700C wheel sizes. Using the smaller 650B wheel means that you can fit a larger-volume treaded tyre for off-road applications, or use a 700C wheel with a tyre of less volume, but with the same rolling radius, when prioritising rolling speed.

We've worked together with HUNT Bike Wheels to develop the tubeless-ready, extra-wide, 650B 'AdventureSport' wheelset: replaceable cartridge bearings; traditional J-bend spokes; easy strip down of the hub system requiring traditional tools only.

Bottle #3

A third bottle cage mount at the base of the down-tube to allow for an additional bottle or tool keg to be fitted. The third bosses are positioned close to the BB to maximise tyre clearance and keep the centre of gravity low. 

FlatMount Brake Calipers

Flat mount disc-brake callipers are lighter, neater, and open up more space within the dropout area for racks and ‘guards. The calliper is mounted to the dropout, allowing us to use a lighter, more comfortable seat-stay.  Up front, the calliper is mounted directly to the fork [via the brake manufacturers adaptor] and offers a cleaner and more minimalist appearance and also provides a compact packaging of the brake caliper.

D-Form Downtube

The DForm down tube is designed by us and tooled exclusively for MASON by Dedacciai in Italy. It is not a simple ‘D’ section and varies in shape from being taller/narrower at the head tube to being wider and lower in section where it meets the BB shell. This shape allows a very wide weld where the tube meets the BB, giving it great stability and ensuring that the weld doesn’t excessively overlap onto the base of the seat tube.

Structural Surface Finish

Re-Machinable Bearing Seats

QuadSlot Seat Tube

3D-Printed Ti Dropouts

We were heavily involved in the development of the highly advanced Reynolds UK, 3D printed Titanium, thru-axle/flat-mount dropouts that we use for the BokehTi and Aspect. The dropouts are extremely precise and lightweight and provide highly accurate and stiff axle retention. The interior is a highly complex structure, only made possible by using this advanced 3D ‘Additive Manufacturing’ process, internal ribs, gussets and guides deal with riding forces and guide internally routed electronic-shifting cables. Alongside the dropouts, we worked with Reynolds to create beautiful new double-bend and tapered titanium chain stays. The stays mate perfectly with the dropouts and combine to give us the tyre clearance and smooth propulsion that we require.

For you this means perfect alignment and extremely efficient power transfer, helping to give our titanium frames incredible ride quality and ultra-distance, multi-surface conquering mastery.

Thru-Axle Front & Rear

31.6 Seat Post

MASON x Dedacciai Ti Tubing

Our BokehTi, Aspect and Aspect Integrale use a full compliment of custom 3AL-2.5V/GR9 seamless tubing. Every tube is designed or shaped specifically for MASON, nothing is ‘Off the shelf’. Dedacciai tooled up for our special ‘Dform’ down tube and all other tubes have bends and profiles developed between MASON, Dedacciai and our frame makers in Italy. THIS is the key to the superb, ‘grin inducing’ ride of these award winning bikes.

Parallax2 Thru-Axle Fork

Unique to MASON. This frame is fitted with our ‘Parallax2’ 465g, Ø12mm thru-axle/flat-mount, monocoque carbon fork. We develop our own custom tubing and wheels, so when it comes to the forks for our bicycles it makes total sense for us to design and tool up for our own fork too. We don’t want to compromise ride-feel, balance and performance by using an ‘off-the-shelf’ and generic product.
Features: Custom layup UD carbon construction, Mason F-Stop axle with clockable axle, allowing you to re-position the release lever as things bed in. TrueTaper steerer, sealed Internal Routed brake & dynamo routing, dynamo light eyelet on crown, triple-boss eyelets on both fork legs, discrete eyelets for mudguard mounting. Huge clearance with full mudguard clearance even when using the largest tyres.

Recommended tyre sizing: 700c x 40mm [45mm Max.] 650b x 50mm/2” [2.1” Max.]