Eclipse X20

The Pirate Ninja

It’s more than fast and light enough to launch a brigand’s attack on an unsuspecting roadie, yet stealthy enough to slip – folded and shrouded – into the subway unnoticed. The Eclipse X20 is as lithe and sleek as a ninja. But with its super-wide 25-107” gear range and lightning-fast Kinetix Pro wheels it’s got pirate-worthy swagger that demands attention. Slice to the heart of the city – whether you prefer a katana, a cutlass, or both. A winning combination if there ever was one. Debate settled.

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N-Fold Technology

The Faster Fold

Folding bicycle design hasn’t changed much in decades. N-Fold Technology is a small but important change that results in a faster, and more compact fold. N-Fold Technology includes new frame and handlepost geometries and spins the front wheel by 180 degrees before the central fold, resulting in a package 40 mm (1.5") shorter. Using N-Fold technology, our bikes are only very slightly larger than the typical small wheel folding bicycle. Bicycles with N-Fold technology can also be folded – easily – in less than ten seconds.

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OCL Joint

Stronger, Better, State of the Art

The OCL Joint is a new reference in folding frame technology. It includes two new patents and everything we know about making the safest, strongest, and most durable frame joint.

  • Stronger, Stiffer — Making the hinge taller and moving the pivoting surfaces outward from the center axis more than doubles overall strength and stiffness and it’s a difference you’ll feel from your very first ride.

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Stronger by Design

Folding bikes have a sometimes deserved reputation for flexy frames. All Tern frames feature patented DoubleTruss technology which turns the rear half of the frame into a three dimensional truss so that it’s much more resistant to torsional forces.

Traditional bike frame seat stays start at the seat tube to create the rear half of the bike. On Tern bikes, the seat stays form a rigid triangle with the seat tube to fashion a continuous structure that extends to the rear axle.

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Smooth TIG Welding

Beauty Meets Function

The normal TIG welding process for aluminum bicycle frames is done by hand and involves the welder laying down a series of small, overlapping beads covering the two parts to be joined. The better the welder, the more uniform the beads. In the smooth TIG process, the welder makes a “double pass”, laying down a second layer of beads on top of the first. These beads are then sanded down by hand in an intensive process that requires extreme care. Done properly, the frame is strengthened because the possibility of stress risers is reduced. And the result is a very smooth weld joining the two tubes.

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Physis 3D Handlepost

3D-Forged = Even Stronger, Stiffer, Better Ride

Flexy handleposts and noodly handling are the Achilles heel of many folding bicycle designs. The Physis 3D handlepost solves this with a massively strong, precision machined design that virtually eliminates flex. The Physis is 3D-forged from a single piece of aluminum, eliminating welds to give a stronger, lighter, and more cost-effective part.

The Physis uses four patented technologies and is 100% serviceable, so all parts can be replaced if needed. It has igus™ bearings for smooth operation and rubber seals to protect headset bearings.

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Syntace VRO 47 Stem

Fitted to You

The VRO 47 stem fine-tune your riding position for speed or comfort. The stem is 47 mm long (14 mm longer than the standard VRO) and it’ll go anywhere from -45 degrees to +90 degrees or even backwards if you want to reduce the reach. And it exceeds Syntace’s brutal in-house test procedures for downhill gear. Custom-built for Tern.

Syntace is a German company renowned for their incredibly light but amazingly strong stems and bars. The Syntace VRO handlebar system used on select Tern bikes allows adjustment of handlebar height and reach for perfect rider fit.

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Ergon GS2 Leichtbau Grips

Relax Your Hands

Once you go Ergon, you’ll never be able to go back to standard grips. They’re just that comfortable. GS2 grips are bigger with softer and more generous wings to reduce pressure on your ulnar nerve and ease wrist strain. The soft kraton rubber main body gives just enough while a textured rubber insert on top dissipates jolts and vibration. Originally designed for endurance mountain bike racing, the GS2 Leichtbau grips make long rides comfortable and provide plenty of options for positioning your hands as you ride. Welcome to 21st century grip technology!

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Stasis Seatpost by Syntace

Strong and ultralight

Syntace makes some of the strongest and precisely engineered seatposts on the market. We wanted the best so we worked with Syntace to develop a 580 mm seat post with a variation of their 3D cold-forged P6 clamp. The Stasis is made from ultra-light 7075 aluminum and weighs only 447 grams. ERS technology delivers loads of fore/aft adjustment for the saddle: you can run the saddle forward for zero offset stiffness, or all the way back when you want more room to stretch in the cockpit. Two bolt micro adjust for infinite angle adjustment.

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Ashima Aero CNC Cartridge Brake Pads

Smooth Stoppers

Ashima pads are the lightest on the market and pack more tech per square mm than almost any other component on our bikes. The CNC machined pad holders are ultra light and the multi-color, multi-function pads feature patented airflow cooling and a wear indicator that shows when they need replacing. So grab a handful. It’s satisfying to know your brakes are in good hands.

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Light and Fast

The Kinetix Pro 507 wheels represent everything we know about making the best possible wheels, costs be damned. We start with the best ingredients: custom ultra-light American Classic hubs rolling on stainless steel bearings; Sapim bladed spokes custom-forged to our specific lengths; Niobium-alloy rims that are light but incredibly strong. A master wheel-builder then hand laces each wheel to incredibly strict standards as defined by the man, Rolf Dietrich. Each wheel is laced and trued, de-stressed with our custom Black Box, trued again, and de-stressed, before the final truing.

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Schwalbe Kojak Tires with RaceGuard Puncture Protection

Liven Up Your Ride

We’re pretty sure the folks at Schwalbe were thinking ‘70s American TV when they named this tire because, yes, Kojaks are bald and more than a little sassy. Comfortable and surprisingly fast, we like the SpeedGrip multilevel dual compound for high levels of grip and low levels of rolling resistance. And there’s the proven RaceGuard protection belt, developed specially with racing in mind. Who loves ya baby? Kojak does. Ol’ Telly would be proud.

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Tern Tail Masked Paint

Super-fine Details

Getting this finish just right needed a LOT of work with our paint factory. It basically involves incredibly meticulous hand-masking to achieve the final result. With the silver/black finish, we hand-polish the aluminum frame to a mirror finish and then follow that with hand-masked black paint. Detail: the shape of a Tern’s tail is echoed in the paint masking.

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General Info
Black/Black Matte
Wheel Size: 24 inch wheels
Speeds: 20
Weight: 10.7 kg (23.6 lb)
Folding Time: 10 sec
Folding Size: 42 x 89 x 76 cm (16.5" x 35.0" x 29.9")
Frame Sizes: One size
Gear Inches: 25" - 107"
Distance: Seatpost to Handlebar: Min: 560 mm (22.0") Max: 700 mm (27.6")
Distance: Saddle to Pedal: Min: 770 mm (30.3") Max: 1040 mm (40.9")
Suggested Rider Height: 148 - 195 cm (4'10" - 6'5")
Max Rider Weight: 115 kg (254 lb)
Frame: Eclipse, hydroformed 7005-Al w/ smooth TIG welding, patented OCL Joint and DoubleTruss technology, Igus bearings
Fork: Aluminum 6061
Handlepost: Physis 3D, 3D forged construction, 4 patented technologies
Stem: Syntace VRO 47, adjustable
Headset: Flux Pro, angular contact cartridge bearings, dual-seal technology, machined aluminum cups
Handlebar: Kinetix Pro, double-butted 7050-AL, for VRO
Grip/Bars Tape: Ergon GS2 Leichtbau
Saddle: Kore Road Performance, SL foam, hollow cro-mo rails
Seatpost: Stasis by Syntace, 7050-AL, hard-anodized
Seatpost Clamp: Syntace OverLock
Front Brake: Kinetix Pro, Ashima Aero CNC cartridge brake pads
Rear Brake: Kinetix Pro, Ashima Aero CNC cartridge brake pads
Brake Levers: Avid Speed Dial 7
Brake Cable & Housing: LiveWire 7.0, anti-compression housing, slick cables, DuPont L3 lubricant, alloy ferrules
Front Hub: Kinetix Pro by American Classic, stainless steel cartridge bearings, ultralight 58 gram design
Rear Hub: Kinetix Pro by American Classic, stainless steel cartridge bearings, ultralight 205 gram design
Spokes and Nipples: Sapim CX-Wing Bladed, custom forged
Rims: Kinetix Pro, matte anodized finish, laser-etched graphics
Tires: Schwalbe Kojak, 40-507, foldable Kevlar bead, RaceGuard puncture protection, 85 psi
Shifter(s): SRAM SL700 flatbar trigger, 2 x 10 spd.
Front Derailleur: SRAM Rival
Rear Derailleur: SRAM Force
Crankset: FSA Gossamer Compact, 50/34T, BB386 oversized aluminum spindle
Cassette/Freewheel: SRAM 10 spd., 11-32T, alloy spider
Bottom Bracket: FSA MegaEVO, BB386
Chain: KMC X10L
Pedals: MKS EZY QR
Shifter Cable & Housing: LiveWire 8.0, sealed alloy ferrules, DuPont L3 lubricant
Bell: Aluminum
Clip System: Magnetix 2.0
Luggage Socket: Yes
Rear Light: BioLogic TailLight
Innovation & Tech Today
December 15, 2014

"This bike is the perfect gift for anyone looking for a full bicycle experience, while being able to fold their bike down for travel and/or storage."

Outside Online
November 25, 2013

"Lots of folding bikes are sluggish and clunky. Not the X20. Thanks to larger-than-most 24-inch wheels and an impressive array of high-end components, the X20 is downright zippy It also weighs less than 24 pounds and folds down to half its size, making it easy to throw in a trunk or cary up stairs."

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LA Times
October 11, 2013

"A superb ride. It has the best of both worlds: a compact fold-up bike with a "big-bike" ride, due to wheels just 2 inches shorter than those of a mountain bike. "

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Czech Online Mag
September 10, 2013

"Celkově je tento model ideální pro dojíždění po kvalitní cyklostezce a spíše po rychlejší rovině, kde naplno vyniknou jeho sportovní ambice podpořené i nízkou hmotností. Trápit se na hladkých pláštích a svazkovém výpletu po rozbité dlažbě, na to je této luxusní verze přece jen trochu škoda."

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June 2, 2013

"Es gibt gute Gründe für den Besitz von mehr als einem Faltrad. […] Mit dem Eclipse X20 kann man jederzeit an einer radsportlichen Jedermann-Veranstaltung teilnehmen."

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May 9, 2013

"Ordet foldecykel er simpelthen ikke et fint nok superlativ for Eclipse X20. Der meget mere tale om en velkonstrueret og bygget sporty kompakt dagligdagscykel som i tilgift kan sammenfoldes. Den kører og opfører sig som en almindelig sportscykel, og giver i tilgift den funfactor med i købet alt for mange dagligdagscykler mangler. Cyklen er svær at sætte i bås hvad der sikkert vil gøre den endnu mere atraktiv for mange. Den ultimative urbane foldekøremaskine for legesyge piger og drenge."

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February 18, 2013

"Possibly the world’s fastest folding bike that you can fold in 10 seconds, Tern Eclipse X20 is fast and light enough to outdo its rival on road."

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February 15, 2013

"Lovingly called the Pirate-Ninja because they couldn’t decide which of the two was more badass, the Tern Eclipse X20 is quite possibly the world’s fastest folding bicycle. It’s a super light and super sleek 24 bike that is built for speed."

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Headset Press
November 15, 2012

"The Eclipse P7i is easily a very good contender for a practical bike. We at Headset Press really like the look of Tern’s, coming in good colours and generally well styled (not common for folding bikes!). They pay a lot of attention to the aesthetic of their bikes and it really shows. So if you’re in the market for a folder or solid commuter bike look no further than Tern."

Read the entire article online here.