The Bossi Strada SS is a titanium road bike that – uniquely – uses cast frame parts and hydroformed tubes, giving the frameset an almost carbon-like silhouette.
In designing the bike, Bossi wanted to make something that “bridges the performance gap to carbon while still maintaining the magical titanium ride quality", all while remaining – in the context of high-end titanium bikes – competitively priced.
Though it will take a bang-on-trendy 30mm-wide tyre, the Summit SS is absolutely focused on road racing. The Australian brand’s Grit gravel bike, Summit endurance road bike and round-tubed Summit road bike cover all other key disciplines.
Alongside framesets, Bossi also produces a line of carbon wheelsets, forks and titanium finishing kit.
A construction unique in titanium
The head tube, seat tube junction and rear dropouts on the frameset are all cast out of 6AL/4V titanium alloy.
Rather than mitring and welding the main tubes onto a conventional round head-tube and bottom bracket shell, these parts instead include ‘the roots’ of each tube. These parts are then sleeved into the tubes, welded and linished (essentially ground back with a belt sander) to a smooth and seamless finish.
The rear triangle uses typical welding around the bottom bracket and at the top of the seatstays.
The tubes themselves are hydroformed into “Kamm-like profiles” to improve aero performance (more on that in a moment) and double-butted to reduce the wall thickness while maintaining durability.
The process sounds similar to Specialized’s Smartweld design as seen on its alloy Allez Sprint, but this is the first time we’ve seen it employed with titanium.
In fact, Bossi claims that “the Strada SS is the only frame we’re aware of that blends all of those elements together”.
The construction is also said to reduce “hundreds of grams” from a typical welded titanium frame, with the Strada SS weighing a claimed 200g less than the brand’s standard round-tubed Strada.
“Incidentally aero”
Bossi is up-front in saying that "the Strada SS has spent exactly zero minutes in a wind tunnel", adding that it has "no numbers for how much faster it is over a 40km time trial at 40km/h either".
This is a refreshingly open approach.
You're unlikely to buy a bike like this for its aero chops and, either way, it's easier to believe an unquantified trust in well-known design principles than a marginal and caveated claim made for a bike ridden at a speed unachievable by most riders.
Indeed, the brand goes on to say "it's aero optimised, so more aero than a traditional round tube, but [we're] not trying to tell people it's going to be a physics-defying weapon built to destroy everything in its class".
With that said, Bossi describes the bike as "incidentally aero", with the aero-shaped cast frame parts, fully internal cable routing and finishing kit all likely contributing to a reduction in drag, albeit a reduction that hasn't actually been tested or modelled.
Fair play, we say.
A bike for life
The Strada SS bike is built around a T47 threaded bottom bracket shell, allowing riders to use pretty much any crankset on the market without the potential headache of a press fit shell.
Similarly, the Summit SS is designed to work with mechanical, electronic or wireless groupsets, with all cables and hoses fully internally routed on the bike.
We’re happy to be proven wrong but, as far as we know, we think this is the only titanium road bike on the market with fully internal cable routing – if you know of another, please let us know in the comments.
The bike is available in a plain brushed finish or, if you want something a bit more bling, you have a pick of four different painted or anodised finishes:
- As seen on the pictured prototype, a single colour on the front two-thirds of the frameset
- Painted to the chainstays, as seen on many classic steel bikes
- A faded blend between two colours
- Pretty much any anodised finish you desire – “if you can dream it, we can do it”
At AU$5,499 (approximately £3,025 / $3,960 / €3,350 ), the frameset is definitely not cheap, but it’s also not that far off what you would pay for a high-end road frameset from a mainstream manufacturer.
For that price, you get a frame, fork, seatpost and clamp, and headset.
The complete build as pictured – replete with SRAM’s top-end Red eTap AXS groupset, Bossi RD1R wheels and the aforementioned Vision cockpit – would set you back a heady $14,499 (approximately £7,985 / $10,445 / €8,835).
Again, that’s a whole lot of cash, but in an era when every brand launches a new model with an outrageous circa-£10k superbike, around £8,000 almost looks like good value… almost.
Full Bossi Strada SS cast titanium frameset specs
- 3AL-2.5V double-butted titanium tubing
- 6AL/4V cast head tube
- 6AL/4V cast seat tube junction with internal seatpost clamp
- 6AL/4V cast dropout
- 6AL/4V CNC T47i bottom bracket
- Linished, seamless welds on head tube and seat tube junctions
- Fully-internal cable routing
- Hydroformed top tube, down tube, and seat tube
- Aero-optimised D shape profiles
- 6AL/4V CNC T47i bottom bracket
- Braze-on front derailleur
- Toray T800 monocoque carbon flat-mount disc fork
- Double ovalised chainstays
- Tapered and lowered seatstays
- Flat-mount disc brakes
- 12 x 100mm front and 12 x 142mm rear thru-axle
- 1.5in–1.5in head tube
- Integrated headset – FSA ACR
- Two bidon cage mounts
- Electronic and mechanical compatible
- D shape aero carbon seatpost
- Laser engraved logos
- Brush finish
- CNC engraved head tube
- Clearance for 30c tyres
- Supplied with optional direct-mount hanger