Specialized is expanding on the ingenious Smartweld technology it first introduced on its alloy Allez three years ago, now adding the novel construction technique to the bottom bracket shell for 2016. The frame weight doesn’t change much but Specialized is claiming stiffness and strength gains that now put the new Allez Sprint nearly on par with the much pricier Tarmac.
The Smartweld bottom bracket shell is a truly brilliant, ‘why-didn’t-I-think-of-that’ piece of engineering, comprising two stamped thinwall aluminum halves and a machined central sleeve that’s all brazed together to form a hollow monocoque-like structure. The much bigger cross-sections not only yield expected stiffness increases in that immediate area; they also allow for much bigger down tubes and chainstays for greater overall frame rigidity.
The key to the specialized allez sprint’s design is the truly innovative three-piece bottom bracket shell. each half is separately formed from flat sheet while the bottom bracket sleeve is turned on a lathe. all three parts are mated together and then brazed to form the final structure
The key to the new Allez Sprint’s heady performance claims is the Smartweld bottom bracket shell
Even better, Specialized says there are substantial improvements in strength and long-term durability, too. Welds typically are weak points for the frame since they’re generally more brittle than the surrounding tubes and situated at high-stress areas. Smartweld moves the weld beads away from the traditional joint locations, shifting them further down the frame tube and positioning them in between two parts that are more similar in shape and where stresses are substantially lower.
Specialized hasn’t yet revealed final claimed weights for the production bikes but the target during the later prototype stage was around 1,100g – almost exactly the same as the current Allez, which only uses Smartweld in the head tube area. That frame isn’t exactly renowned for its rigidity but the new Allez Sprint supposedly more than makes up that gap.
When it’s fully built, the smartweld bottom bracket shell has a visible seam but it’s still quite subtle
Shaping like this was previously only possible with carbon frames
“Ultimate weight wasn’t the criteria for this,” said Specialized senior advanced R&D engineer Chuck Teixeira, an industry veteran with more than three decades of experience under his belt, much of which was spent at Easton. “This is more of a crit bike so we wanted really good stiffness. That comes at the expense of a little extra weight. We have lots of opportunity to make it lighter. In many of the pedaling tests, it’s stiffer than the Tarmac.”
As part of that rather narrowly focused design goal, Specialized is launching the new Allez Sprint in just two complete builds and one frameset to start – none of which have provision for a front derailleur. By Specialized’s reasoning, bikes specifically used for criterium racing or fast lunch rides simply don’t need that wide a gearing range, and the bare seat tube that results looks sleeker and cleaner.
Nope, your eyes aren’t deceiving you. there is no front derailleur mount, and no way to install one
Notice anything missing?
That approach is undoubtedly going to be met with a healthy amount of resistance from riders who might be interested in such an advanced alloy chassis but need more realistic gearing – including us here at BikeRadar. That said, Specialized is already hedging its bets. Front derailleur-compatible Allez Smartweld frames (that are similar but with taller head tubes and slightly slacker seat tubes) will be released in December, just three months after the release of the 1x-specific ‘X1’ models in September.
Kudos to specialized for wrapping all of the new allez sprint options in pleasantly understated paint schemes. this allez sprint comp will come with sram’s rival 1 groupset
The Specialized Allez Sprint Comp X1 will cost $2,000 with a SRAM Rival 1 groupset. All international pricing is TBC
The top-end specialized allez sprint expert will come with sram’s force 1 groupset
The Specialized Allez Sprint Expert X1 will cost $2,600 with a SRAM Force 1 groupset
Also available is a bare specialized allez sprint sl frameset with a sleek polished finish that not only looks fantastic but will save a fair bit of weight, too
Specialized will also offer the new Allez Sprint in a frameset, complete with a gleaming polished finish for $1350
What the future holds for Smartweld
What’s even more interesting is what Smartweld might do for other alloy frame designs. After all, it’s not just road bikes that can benefit from big stiffness and strength gains, and aluminum’s inherently lower costs will always make it more of a mass-market commodity than carbon frames, which have far greater workforce costs associated with their production.
Some level of Smartweld technology could theoretically be integrated into nearly every one of Specialized’s alloy bike collections, including the CruX, Stumpjumper, Crave, Camber, Enduro, and even the Fatboy.
Specialized first introduced the smartweld concept on the allez’s head tube, which is formed as a single piece and features far more complex shaping than a traditional mitered piece
Smartweld will certainly find its way into other Specialized bikes at some point
“We also have a number of other bikes in line for this technology and this approach is not limited to hardtails, either,” Teixeira said. “Ideas are floating around that would make this work on suspension bikes. How fast we move comes down to our aluminum product team’s bandwidth and platform strategy. I wish we could do it all tomorrow, but that’s just not going to happen.”
“The future bikes that we’re going to be folding this into – it just opens up a bunch of design opportunities for us to make better and better structures.”
Perhaps best of all is that all of this performance is coming at alloy-level prices that plenty of regular riders will be able to afford. Specialized has yet to release full international retail prices for the new Allez Smartweld bikes and frames, but even just based on the US figures, the landscape for value-minded buyers has never looked so good.
For more information, visit the Specialized Allez Sprint page.