THE NEXT BEST THING IN NEAR NET
Too much of the marketing for carbon fiber bikes is focused solely on the material: how high is the modulus? The rationale being that since modulus is a measure of stiffness, then surely the higher the modulus the better the material! And if higher modulus carbon fiber is more expensive, then clearly it must be better! It ain’t always true. That’s like saying white bread is better for us than whole wheat simply because it’s undergone more processes in it’s manufacturing.
The truth is, making the lightest, stiffest, most comfortable and most durable frame is not just about what carbon fiber you use, but how you engineer to use it and how you manufacture with it. It’s about what you lay-up and where. It’s about how you compress and set the fibers. Design and engineering are King. Compaction is Queen. And material is the Princess that the media and marketing love to write stories about.
We’ve taken our revolutionary Near Net dual-molding manufacturing process, that utilizes both silicone and polystyrene internal cores to support the frame shape while it is being pressurized within the steel mold, and added a vacuum purge procedure before molding that compresses and eliminates all air between carbon plies. Compaction is absolutely optimized. Not only is weight reduced while stiffness
and strength are increased, but over-reliance on fragile and harsh-riding super-high modulus fiber is minimized. The result is a lighter, faster, stiffer, stronger frame that simply rides better.
RIDE TUNED FOR YOU
The benefits of a properly fitted bike have been recognized for years. It is essential for injury prevention and maximized efficiency. And it is the primary
determinant in assuring the greatest comfort and enjoyment while riding.
Our first road bikes introduced in 1988, the Quest and Axis (for Jamis history
buffs, this later became the Eclipse), were designed in consultation with Bill Farrell, inventor of the first bike-sizing tool, the Fit Kit. Back then, bike companies generally plotted a single geometry on all frame sizes: the blow ‘em up or shrink ‘em down solution – lazy, cheap and thankfully long ago obsolete. We learned from Bill early on how to tune our frame geometries and specify component sizing to account for the multiple variables needed for a proper fit for every frame size. We’ve been honing our fits for every bike, every year, ever since.
But fit is a two-dimensional calculation. Stack and reach. How tall, how long, for me? It’s in the third dimension – the SST dimension– that Jamis continues to make a difference for you.
Slight changes in tube diameter have a significant impact upon performance.
As diameter increases, strength and stiffness increase along the length of the tube as well. Whether in aluminum, steel or carbon fiber, we vary the cross-section and sometimes even wall thicknesses to fine-tune the performance and comfort characteristics of each frame size.
SST — Size Specific Tubing– optimizes ride quality and assures the lightest possible weight for each frame size. By varying the diameters of the tubing in the main frames of each of our frame sizes (and sometimes even in the seatstays) by 10 – 20%, we can produce a bike that not only fits like a glove and handles precisely, but accelerates and climbs explosively and offers just right
compliance for every rider, every frame size.
THE NEXT GENERATION OF BREAKING THE WIND
Our chief design criteria when engineering the new Xenith frame platform was to make it lighter, stiffer, more impact resistant, more comfortable and more aerodynamic. In that order. The listing of “more aerodynamic” as last in this inventory of performance attributes is not without intention. Frame design is always about compromise; it’s always about prioritizing one riding attribute over another. Designing a frame to be the most aerodynamic, the lightest, the stiffest AND the most comfortable is simply not possible.
The professional riders of Team Jamis/Hagens-Berman p/b Sutter Home were adamant about what to do when told we were working on the next gen Xenith and wanted their feedback on every element of the frame they had been racing (and winning) on before our engineering team would commence. Their response was unanimous — if you can make it stiffer for sprinters likes JJ, great; if you can make it lighter for hill climbers like Janier and Tyler, great; as for impact resistance, comfort and aerodynamics, sure, if you want, but don’t change a thing about the fit, handling or the balance of the bike, it’s perfect as is.
With the teams’ design guidelines defined, we did lighten and stiffen the new Xenith frameset and we did increase impact resistance and comfort by implementing NearNet SPV. But we also improved aerodynamics. The advantages of our original Windshield fork, which shrouds the rear-facing front brake on our T2 time trial bike within the fork blades, has been proven time after time in the wind tunnel and on the racecourse. That project and experience led us to develop a lighter version for use on the new Xenith SL, Team and Pro. Our new Windshield II fork design with trailing direct-mount brake reduces drag by nearly 4% compared to last year’s fork with leading caliper brake. An advantage you’re sure to appreciate the next time you’re pulling a breakaway or closing the gap solo.
KEEPING IT ALL INSIDE
Before electronic shifting was a commercial reality, we were torn on the benefits of internal cable routing. The advantages – stunningly clean aesthetics, no cable stops to chip, ostensibly cleaner cabling systems – were counter-balanced by its chief disadvantages – the extra weight and friction of full-length housing or interior guide tubes and the labor-intensive challenges of installation and replacement. Given our engineering emphasis on performance-first design, we previously outfitted our road-racing Xeniths with externally routed gear and brake cabling. It was light. It was simple. It was easy to maintain. But with electronic shifting, it makes much more sense to run everything inside.
Attaching and affixing wiring and harnesses externally is every bit as laborious (think cable ties, adhesives and external mounts) as running them internally, where they are much more protected as well. Not to mention, running this stuff inside just looks right.
Which is why every 2014 Xenith is equipped with our new Adaptive Cable Entry system. ACE allows our frames to elegantly and easily manage the internal routing of brake and derailleur cable housing OR electronic Di2 wiring. Xenith models specified with standard cable-actuated drivetrains will be outfitted with ACE plates with integrated cable stops. But we also include with every bike an extra set of ACE plates for Di2 wiring should you ever wish to make the jump to electronic shifting.
THE EVER EVOLVING BOTTOM BRACKET
There are a number of BB standards in the bike industry right now. Here is what you will find on our bikes, and why. Traditional: The BSA standard. The standard forever. A steel BB spindle, 17mm in diameter, turns within a 68mm or 73 mm shell and upon sealed cartridge ball bearings that are threaded into the BB shell. Not particularly light, not especially stiff (by today’s standards), but reliably durable and definitely cost effective.
External Bearing: The BB shell is still 68mm or 73mm wide and just under 35mm in diameter, but the bearings have been moved outside the BB shell (Shimano Hollowtech II, SRAM GXP, FSA MegaExo). This allows the spindle diameter to be increased over 40% to 24mm and hollowed for a huge stiffness increase with a significant weight reduction. The larger diameter spindle does not compromise bearing size because all bearings now reside outside
the frame. The spindle is also better supported with bearings nearer its ends rather than its center.
PressFit30: PressFit30 (SRAM) is a derivative of the BB30 (FSA) system. BB30 increases the spindle diameter to a whopping 30mm for the ultimate in stiffness. But because the BB shell’s inside diameter is also increased from just under 34mm to 42mm, bearing size is not compromised. The challenge with BB30 is that bearings are pressed directly into the frame, leading to durability issues if there are any frame or bearing tolerance deviations. The beauty
of the PF30 system is that bearings are housed in nylon cups that are pressed into the frame’s bottom bracket shell. Bottom-line advantages of the PF30 system over BB30? Improved bearing-to-shell interface, greater bearing durability and simplified installation.
BB386EVO: The BB386 EVO bottom bracket design amplifies the benefits of the proven BB30 and PF30 system. It takes the lighter, stiffer 30mm alloy spindle from the BB30 design, incorporates press-fit bearing cups from the PF30 system and marries both to a wider 86.5mm BB shell (which is the same width as on a standard 68mm shell with external bearings). All without changing Q-factor. Why a wider shell? It allows us to increase the diameter of our seat and down tubes at the BB shell a full 30%, for increased stiffness where you really need it. We can also optimize chainstay design with an increased diameter that doesn’t crowd the rear tire.
11-SPEED SMOOTH SHIFTING
SHIMANO: Dura-Ace 9000 and Ultegra 11-speed move to the next generation. Reduced shifting effort lets you concentrate on riding. More control thanks to improved ergonomics. Unbeatable reliability gives you confidence. Tested in competition and taken to victory by pro riders in all conditions.
SRAM: The new RED22 11-speed group represent SRAM’s most advanced thinking yet on drivetrain performance. The ErgoDynamic Shifters, Yaw front derailleur technology and Exact Actuation rear derailleur technology provide the perfect interface between rider and bike while delivering precise, efficient shifting.
SRAM’s 11-speed chainring is developed for maximum chain control, each tooth’s thickness is precisely CNC-machined to support the chain’s inner and outer links perfectly. Each X-SYNC™ chain ring fits a single, universal spider—allowing you to change rings without removing the crank arm. Their 11-speed cassette delivers an incredible gear range while maintaining even, optimized steps.
FIT FOR ALL
Though we do make bikes with frame geometry and component sizing specifically targeted for women, not every woman is best suited or fitted on such a bike. We want to be clear about that from the outset. As always, the best advice for buying a bike is to go to your bicycle retailer, where you can be properly fitted on a bike. One of our “unisex” just might be the perfect fit for you (though a swap for a saddle with a wider sit-bonesplatform will likely be recommended). But if you discover that you are, in fact, best fitted
on one of our Femme geometry bikes, of which there are many, here’s what you’ll find:
• Top tubes will be shorter; stems shorter too, with seat tube angles possibly steepened, all to reduce the distance from saddle-to-bar for a more comfortable reach.
• Head tube angles may be relaxed and fork rake increased to eliminate or minimize the potential for wheel-toe overlap.
• Bottom bracket height may be dropped so standover clearance is increased and center of gravity is lowered.
• Handlebars will often be narrower with a shorter reach to the flats and drops.
• Brakes/Shift levers will often have a shorter reach as well and cranks arms may be shorter for any given frame size in comparison to the unisex version.
• Saddles will generally be shorter and wider, often with a pressure relief zone.
• We may even alter the weight and stiffness of our frame materials to better suit a lighter-weight rider (see SST info below)
And we make all our Femme bikes in a broad sizing range – from 44cm to 54cm, or 14” to 18”, so you can be assured of finding a Jamis Femme that fits perfectly.
TAKING IT TO THE LIMIT
All our frames and forks are tested continually to meet or exceed (in some cases, well exceed) EN standards 14764, 14765, 14766 and 14781. We conduct these tests at our frame manufacturing facilities, but we also use EN accredited testing laboratories such as Intertek and SGS to verify the results of our own tests. If these tests aren’t telling us everything we want to know about our bikes, we increase the loads and cycles, or we determine another way to test. Where current hydraulic testing machines, jigs and hardware aren’t up to the task of emulating some of the forces and impacts our bikes might be subject to, we’ve designed our own.
We relentlessly cycle test for fatigue from pedaling and torsional forces on every single frame size, with deflection tests for stiffness at every point of the frame. Brutal impact tests with massive weights dropped on fixed frames or forks are performed. Then reversed, with weights attached to the frame, the frame hoisted to a given height depending upon product type, then released.
This destructive testing is enormously instructive and important. And it is in continual process. But it’s our ongoing non-destructive testing of frames and forks fresh off the factory floor that’s just as vital.
For our carbon fiber frames, EVERY frame is weighed to make sure it’s neither resin rich nor resin deficient. We also measure the stiffness of each frame in 6 critical areas as a check on lay-up production. Each deflection test must fall within 5% of the standards our machine and field-testing have established. This weighing and stiffness deflection testing guarantees every single frame we produce meets all Jamis manufacturing protocol and will deliver the ride qualities we defined and demand.