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Frame Notes

CARBON FRAMES

Now in partnership with Criterion Composites Santana has engineered and produced a state of the art molded tandem frame right here in California! A monocoque design produces an incredibly strong and lightweight frame with a high stiffness to weight ratio. That’s why it’s the preferred method for top of the line single road bikes, but no bike company had committed to the engineering and tooling necessary for a monocoque tandem due to the smaller volume in what they consider a niche. Besides offering stunning looks and incredibly lightweight this engineering project has resulted in the most comfortable tandem yet.

CARBON FRAMES

and BILAMINATE DAMPING™

Lighter bikes:
How much faster?

This age-old question—and the resulting debate between engineers and enthusiasts—has finally been settled. Engineers had claimed weight was relatively unimportant. They insisted that any bicycle, even one weighing 100 pounds, would be equally fast on a totally-flat century. Armed with cryptic formulas, engineers wanted us
to believe a heavier bike was only a disadvantage when accelerating or climbing. Cycling experts (including magazine editors, lionized builders and winning racers) knew better. A lighter bike, they declared, was the true path to speed and performance. Want to ride faster? Buy a lighter frame and equip it with lighter components! Saving a pound of rotating weight (wheels and pedals), they told us, was as good as saving two pounds of frame weight. Better yet, we were assured, saving two pounds at the frame was as good as saving four pounds of body weight. Whose argument won? Most of us (this writer included) sided with our heroes and ignored the engineers. After all, which is more fun: dieting, training, or shopping for lighter wheels?

After we invested in our carbon frames, titanium hardware and featherweight wheels we felt hours faster. At the very least, we convinced ourselves, our finishing times were improved by dozens of minutes. Now that thousands of enthusiasts are using watt me- ters that accurately record rear wheel power output, however, repeated 32 real world testing proves that those darned engineers were right. The effect of bike weight on speed is easily quanti- fiable, and conforms to Newtonian Physics. Even on an exceptionally long ride a lighter bike is only a few seconds faster. Minutes faster? That was an impossible fantasy.

Watt Meter Findings

• On a totally flat 100-mile ride, a pound of extra weight will slow a cyclist by about 8 seconds (due to increased rolling resistance).

• On a challenging century, a pound of extra weight will slow a cyclist by about 30 seconds.

• On Alpe d’Huez, where the gradient averages 7.9% for 8.6 miles, pro riders using watt meters have verified what Isaac Newton proposed centuries earlier. On this famous climb, the energy required to lift a pound by 3,500 vertical feet will cause solo competitors to reach the summit about 30 seconds later.

The difference between a pound of frame weight and a pound of wheel weight? Less than a second. Excess body weight, which needs to be both lifted and nourished, has a bit more impact than excess bicycle weight.

Discouraged by this news? For tandem riders it only gets worse. When engineers insert doubled power, their formulas confirm that
a tandem’s frame weight becomes half as important. If your tandem’s frame is a pound overweight, for instance, you and your partner will finish a challenging century (or reach the summit of Alpe d’Huez) about 15 seconds slower. Unless you can escape the laws of Newtonian Physics, on most tandem rides the speed advantage of a pound-lighter frame won’t exceed 10 seconds.

Can Lighter be Slower?

While a lighter frame can’t possibly save you more time than the aforementioned examples, it might actually make you slower. If your frame doesn’t adequately resist pedal-induced flex, energy that could have propelled you forward will instead be wasted in lateral frame distortion (which creates heat instead of propulsion).

Because the faddish “open” tandem frames are undeniably flexier, these suddenly popular designs with their missing frame tubes are apt to reach the summit behind a pound-heavier frame with all tubes present. (Legs are also heavy, but finding a tandem partner with missing limbs won’t cause you to win races.)

Although the advantage of a lighter frame is less than most of us formerly believed, the energy required to accelerate and/or lift excess weight cannot be denied. While your body weight is difficult to control, and the lightest bike components may fail or wear out, a light and well-designed frame should provide decades of reliable performance. Because a lighter and more efficient frame
is more enjoyable to ride, you’ll use it more often. Extra use is the factor that easily justifies a frame’s expense. If you spread the cost over a number of years, Santana’s lighter and more efficient frames become a healthy bargain and a superior long-term investment. Since the effect of weight is relatively small (and the lightest frames from leading tandem builders are all within a two-pound spread), is it possible to believe a new frame will allow you to keep up with faster couples? Better yet, some might ask, is there a new technology that will allow you to finish ahead of teams that are younger, thinner or stronger? Actually, there is. We call it Bilaminate Damping™.

More Important than Weight

Even though most cyclists haven’t yet heard of Bilaminate Damping™ (Santana’s specific application of a phenomenon engineers refer to as Constrained Layer Damping or CLD), this exciting technology is a game-changer that’s helping engineers at Boeing and Ford to define the next generation of airplanes and automobiles. Santana became aware of constrained layer damping after we tried to understand dozens of reports received from owners of our Beyond frames built with IsoGrid®* carbon tubing. Most of these couples had upgraded from a previous Santana, and nearly all reported longer rides at higher speeds. Especially intriguing were reports from competitive seniors who claimed their Beyond had “turned back the clock” and was allowing them to regain performance they’d lost through aging. Because Santana’s design team knew these fantastic reports couldn’t possibly be explained by the 6 lb. weight of our Beyond frame (which is only a pound-and-a-half lighter than our frames built with titanium or scandium), we challenged a group of engineers to provide an explanation. Their three word response, constrained layer damping, encouraged a surprising path of discovery.

Following four years of additional research and ride testing, Santana understands constrained layer damping well enough to explain why you’ll feel younger. Further, we realize how an advanced version of this technology (i.e., Bilaminate Damping™) is actually more critical than frame weight, and can enable you to enjoy longer rides and finish minutes faster.

Interested? Continue reading to discover an unexpected source of cycling performance months before your bike-racing buddies read about it in their favorite magazines.

What’s the Buzz?

If you place your fingertips on your frame while you ride, you’ll sense the vibration that occurs as the result of your wheels rolling along the road surface. Experts confirm that all materials resonate, and that thin sections of high strength materials will continue to reverberate indefinitely. Your bicycle frame not only resonates like a cymbal, the lighter and stiffer the frame, the greater the vibration.

This explains why a resounding wind chime can be produced from the same materials that create light bicycle frames (i.e., aluminum, steel, titanium, carbon and even bamboo). The difference, of course, is that the sustained notes of a wind chime are pleasant. Sustained road vibration isn’t. While the vibration we sense through our fingertips seems innocuous, miles of exposure to road buzz has a debilitating effect on human joints and muscles. The faster the speed, the greater the road’s impact. The lighter the bike, the greater the reverberation. Even on the smoothest courses, competetive speeds and bikes take a toll on performance, limit your endurance and makes you feel old.

Doesn’t a carbon frame damp vibration? Although certain materials won’t resonate as efficiently as others (which is precisely why discerning cyclists prefer the comfort of titanium over carbon, and carbon over aluminum or steel), the degree of vibration damping between various high strength materials is comparatively small. A light and stiff racing frame built from titanium or carbon can be less comfortable than a recreational frame built from aluminum or steel.

How Bilaminate Damping™ Works

When two materials that resonate at different frequencies are bound together, each inhibits the other’s ability to resonate. Engineers call it “Constrained Layer Damping.” Additionally, if the weights of the materials are roughly equal, the two frequencies cancel each other. The effect of Bilaminate Damping™ is immediate and profound. Vibration is terminated. Boeing’s initial plan for their 787 Dreamliner was an “all-carbon” stucture. Partway through development they changed the design to approximately equal weights of carbon and aluminum. Through careful engineering and the use of constrained layer damping (CLD), weight did not increase. Instead, vibration disappeared. A flight in a 787 will change your perception of air travel. Because the quieter plane is more comfortable, flights are less fatiguing. Once you’ve experienced the difference, other jetliners become second rate.

The Ultimate CLD

Bilaminate Damping™ is Santana’s term for an advanced adaptation of constrained layer damping. Typical CLD is acheived by bonding structural and non-structural materials (usually elastomers) in unbalanced ratios. With this simple approach, vibration is merely reduced. Employing VyaTek’s patented ExoGrid® and IsoGrid®* technologies, Santana eliminates the bonding layer by using extreme heat and pressure to fuse together a proportioned and complementary pair of ultra-strong materials. In short, other CLDs add weight to reduce vibration. Santana’s Bilaminate Damping™ eliminates vibration without adding a single gram of non-structural weight.

*IsoGrid® and Exogrid® are trademarks for Vyatek’s patented, cutting edge method for creating the world’s finest hybrid composite carbon/metal tubes.

THE STORY BEHIND ISOGRID®

In the early ’90s, after the fall of the Berlin Wall, American aerospace companies scrambled for alternate markets. One of those companies, Simula, decided to use defense technology to build advanced equipment for athletes. Their sports division headed by Howard Lindsay courted the leading innovators in the cycling industry, including Cannondale, Answer, Trek, and Santana. In 1993-94 Santana worked with Simula to develop a one-piece carbon fiber tandem frame. The insurmountable problem was the cost of molds that would be limited to one specific size and geometry. Eventually Simula launched their own brand of single bike, High Zoot, which although incredibly advanced, was too expensive for mid ’90s mountain bikers.

In 1997 Lindsay was recruited by True Temper and worked for three years as dual Vice President (heading both Engineering and R&D). In 2000, when Simula opted to sell their sporting goods division, Howard left True Temper and formed VyaTek to buy Simula’s patents and technology. In 2002 after patenting a way to manufacture carbon fiber bicycle frames without troublesome glue or immutable molds, he excitedly contacted Santana.

Wilson Sporting Goods licenses VyaTek’s IsoGrid® technology to produce the racquets used by Venus and Serena Williams. Two days after agreeing to give the new racquets a one week trial, the world’s most recognized female athletes switched to IsoGrid®. Their reason? See if the following attributes sound familiar: Lighter weight, higher velocity, greater accuracy, and reduced muscle and joint strain.

Other licensees include Scott (ski poles for World Cup racers), Matrix Motorsports (racing technology for German car makers), and Holland Cycles (single bike frames).

*IsoGrid® is a trademark for Vyatek’s patented, cutting edge method for creating the world’s finest hybrid composite carbon/metal tubes.

TITANIUM FRAME NOTES

Other builders combine standard single bike tubes (including a teensy pair of chainstays) with impressive looking down tube and bottom tubes made from heavier industrial pipe. The resulting titanium tandem frame weighs more than Santana’s aluminum frames. Additionally, due to the unfortunate combination of a round bottom tube and undersized chainstays, these frames lack drivetrain stiffness and efficiency, a performance handicap that becomes obvious during out-of-saddle sprints and climbs. Finally, the use of relatively heavy gauges negate titanium’s famous comfort.

Santana is the only builder using a custom-drawn tandem-specific titanium tubeset. While it is often hard to spot differences in tubing, here are three places—all exclusive to Santana—where a visual inspection will verify the superior performance of our titanium frames.

• Oversize taper-diameter stays are properly ovalized for tire and chain clearance.
• The world’s only oversize taper-diameter titanium downtube.
• A bottom tube that is larger and properly ovalized.

Why settle for 30% less when Santana’s titanium tandem frame is a Ten?

ALUMINUM FRAME NOTES

Whereas other builders have saved money by switching to unbranded tubesets from Taiwan, Santana continues to work with Easton to draw superior tandem specific tubes.

• Our custom-drawn 20/10/20 thinwall double-butted 7000-series Santana/Easton aluminum tubing is half the weight, 55% stronger and transmits 60% less road shock than 25/25/25 plain-gauge 6000-series tubing found on other aluminum tandems.
• 35mm top- and lateral- and seat-tubes
• Conical 44–54mm down tube
• 65x35mm ultrawide oval bottom tube
• Comfortable quad-butted seat stays strengthen the brake boss weld zone
• 43x26mm oversize unindented chainstays
• While other aluminum tandem frames deliver an uncomfortable ride and weigh-in at 10 pounds (heavier than our steel frames), Santana’s aluminum frames weigh just over 7 pounds.

NIOBIUM FRAME NOTES

CroMoly, the typical steel alloy that’s been used for decades, is commonly drawn to 9/6/9 gauges. The seamless CroMoly used by Santana can be drawn to a higher-performance 8/5/8. Some tubing manufacturers harden their tubes in order to achieve 7/4/7. Because hardened tubes are brittle, a frame built from these tubes is more easily damaged and has a shortened fatigue life. While hardened tubes aren’t a bad choice for a (more disposable) single bike, a good tandem should endure for decades.

In concert with German car manufacturers, Columbus has developed a lightweight alloy tube to protect passengers against side impact intrusion. Columbus’ amazing Niobium is not only an achievement in automotive safety, a double-butted version of this tube heralds a new era of bicycle design. Because this new steel alloy gets its strength from rare elements instead of a risky heat treatment process, dependable impact-resistant tubes can be butted to 6/3/6 gauges. Since Santana alone builds tandems from this material, if you want the planet’s lightest, strongest and fastest steel tandem, don’t settle for anything less than Santana’s Spirit.

SCANDIUM FRAME NOTES

When Jim Easton inked a deal with the world’s only source of refined scandium, the rare element found only in Soviet missiles and fighter planes became available to the world of sports. When added to Easton’s 7000-series aluminum, Scandium aligned and tightened the grain structure to create home run-hitting baseball bats and race-winning bicycle frames. Unfortunately, Easton naively used “Scandium” to identify their revolutionary new alloy, thus paving the way for counterfeiters and con-artists. Because international law won’t protect the name of an element, anything can be branded Scandium, even if it doesn’t contain a single molecule of this expensive alloying element.

While Easton’s Scandium is a worthy challenger to titanium and carbon tubesets, various builders, magazine test editors and consumers who’ve only experienced non-Easton “Scandium” haven’t a clue. If you’re seeking real performance instead of “fool’s gold,” insist on Scandium from Easton.

Following years of development and testing, Santana and Easton Sports, Inc. joined forces to create an exclusive Scandium tubeset for tandems. When added to Easton’s 7000-series aluminum, Scandium aligned and tightened the grain structure to create race-winning bicycle frames. Since Santana alone builds tandems from this material, if you want the planet’s lightest, strongest and fastest aluminum tandem, don’t settle for anything less than our eSCape. 

Santana, in order to gain hands-on experience with this unique alloy, became one of Easton’s initial customers for their Scandium tubing, and used it to build a limited series of Stylus single bikes. Following years of development and testing, Santana and Easton joined forces to create an exclusive Scandium tubeset for tandems. Since Santana alone builds tandems from this material, if you want the planet’s lightest, strongest and fastest aluminum tandem, don’t settle for anything less than our eSCape.

FRAME FEATURES

1. Evolution™-sized head tube – Instead of a too-small head tube with innocuous machined edges, Santana’s head tube gets its strength from a diameter that allows stronger Evolution (1-1/4″) sized headset, fork and front stem.

2. Integral cable adjusters – Santana designed special braze-ons and moved the adjusters up front to allow captains to fine-tune derailleur indexing and rear braking—easily and comfortably, while riding.

3. Easy-adjusting eccentric – Santana’s elegant one-piece eccentric allows quick, easy and precise chain retensioning with a lightweight pin tool and 4mm allen wrench. You’ll never use a hammer or pry bar again.

4. Round top and lateral tubes – Some builders ovalize top and lateral tubes even though torsional rigidity in these areas is essential. Tests prove these misplaced ovals add weight and rob performance.

5. Rack and fender capability – Santana installs threaded fittings for attaching front and rear racks and fenders. Steel forks include mid-fork through-bolt braze-ons that accept the stiffer, lighter and more secure Custom Lowrider rack from Tubus. Carbon-V forks accept standard lowrider racks.

6. 160mm frame spacing – Because “dishless” (symmetric) wheels with widely separated flanges are 30-80% stronger, Santana’s frames are built to accommodate them. Further, 160mm spacing offers improved shifting, and clearance for today’s large discs and tomorrow’s 11th cog.

7. Disc brake ready – To add a disc brake to other tandems you can spend hundreds to modify your frame and buy a new wheel. By contrast, Santana tandems that don’t already have a disc or drum are ready—with the correct hub, frame clearance and Santana’s versatile platform-style braze-on that facilitates easy installation of various brands of disc brakes or the venerable Arai drum brake.