650B Touring Bike

This brief for this build was a long distance touring bike with the capacity for daily commuting. In the spirit of the traditional french touring bikes it is designed to carry a front load affording compact chainstays without the need for rear pannier heel clearance. 

The frame is fillet brazed from a combination of columbus spirit and life tubing. The resurgence in 650b is great for allowing generous tyre volume at the same time as achieving frame geo for a small rider. It features bentley components low mount rear dropouts, internal rear brake line routing, Llewellyn stainless downtube and chain stay gear bosses. The sloping top tube results in good standover and a good amount of exposed seat post for comfort.

Tyres are WTB horizon 47c setup tubeless on Stans crest mk3 with 23mm internal width. Hubs are SON SL dynamo and King R45 centre lock.

I wanted this bike to have all weather capability with full length HONJO fenders and integrated dynamo lighting. Bentley came to party with CNC machined stainless dropouts to suit the SON SL connectionless front hub, grounding through the left side and sending the power up the inside of the right. The Reynolds 853 disc blades allowed for low trail geo and the crown has been modified to remove the caliper holes, add top mount rack bosses and the under crown fender mount. The fork legs feature mid blade rack bosses, custom turned from stainless to pierce the opposite side when silvered in to reduce the peak stress. 

As soon as I saw the swift industries sugarloaf I new that this would create the versatility for everyday commuting and when combined with the mini roll top panniers with provide plenty of luggage space for adventures.

Not happy with any off the shelf solution for a basket and low mount pannier, I constructed a custom basket rack from 4130 tubing, including a mount for the SON edelux lamp and additional support for the fender. The lines of the custom rack are intentionally aligned with highly regarded tubus low mount rack.

The SON rear light is mounted to a modified brooks cambium inspired by a lovely bike from MAP cycles, with the wiring entering the downtube through a di2 grommet in a stainless boss and exiting from the end of the thomson masterpiece seat post.

The white industries G30 cranks are spec'd with a "super" compact gearing of 32/42 which together with the SRAM force 22 running a 32 rear cassette provides for a good loaded climbing gear at the same time as good top end.

The salsa cowchipper bars provide a nice wide position in the drops for when things get rough and the SRAM hydro with 160mm centre lock rotors give all weather braking performance.

The utilitarian grey paint was beautifully applied by velopaint with small bands of colour that coordinate with the swift bags, busyman bar tape and limited edition chris king/spur cycle bell. 

Approx complete build cost $9k AUD


The design brief was a bike capable of performing both the duty of an endurance road bike while also being capable of tackling adventures on typical Australian rural dirt roads. I resisted the temptation to design for 650b x 2.1 clearance due to the intended use being bias towards on road capability and not pure off road (that bike is next :)). The result is a form not compromised by excessive clearance when running closer to 700 x 30mm and bang on with 35mm tyres.

The numbers are;

Rider 178cm

Head tube angle 72deg

Fork offset 47mm

Seat tube angle 73deg

BB drop 72.5mm

Reach 391mm

Chainstay 422mm

Wheelbase 1024mm

head tube length 147mm

seat tube length 550mm

The bike is designed to cover long distances in a speedy manner so the position is close to that of a conventional road fit. The axle to crown of the enve gravel road fork is great as it allows for a good length head tube when using a lowish BB. Using a slightly sloping top tube allows for balance between comfort from seat post compliance and space for a frame bag. 

The frame is fillet brazed using Columbus spirit HSS tubing with a reynolds 853 oval top tube. The use of the large section down tube (GX shape) and oval top tube gives in a torsionally stiff frame that feels responsive to the rider when cranking hard on the pedals and precise when high speed cornering while the steel ride quality is maintained by the use of a traditional 28.6 seat tube with 17mm seat stays. The seat clamp is an integrated design from bentley components in Yorkshire and like all bottle bosses is stainless.

Using the new T47 BB format has allowed for internal routing through the down tube and into the chain stays with a 30mm spindle. The internal routing uses full length stainless tubing and the main tubes are reinforced at each point it enters to frame tubes to reduce risk of fatigue failure from the stress raiser caused by the hole.

The tapered 34/44 head tube results in a smooth flow into the fork as well accommodating an external 44mm bottom cup for the 1-1/4 tapered steerer.

It uses a full SRAM force 1 group set with a 42t chainring and 12-36 cassette, which for a fan of single speeds results in a completely usable speed range of 8-50kph out on the road. Wheelset is a Enve 3.4 disc with Chris King hubs, converted to tubeless using the new silva tape, running Clement X'PLOR MSO 36mm for gravel and dirt and 35mm compass bon jon pass for speedy road use.

I had a custom half frame bag made by stealth in NZ. I also used his front dry bag harness. I used a wildcat seat pack, which with its quickly removable tapered dry bag means you can chuck it in the tent. I put some pics in from the ride I did a couple of days after finishing the bike. Went on a solo mission to Melbourne taking in some parts of the wilderness I hadn't been ti before. Did a bit over 800km in 5 days with almost 200km of dirt and 13km of climbing. 

Approx complete build cost $10k AUD