Eclipse S11i

The Ultimate

We set out to build the ultimate in two-wheeled urban transport. No price point targets, no competitive analyses, no focus groups. Just a bunch of guys living in Taipei, Taiwan; Austin, Texas; Turku, Finland; Stuttgart, Germany; and Schaffhausen, Switzerland — otherwise known as the Tern product team — working together in the cloud and designing our collective dream bike for urban commuting.

Photo may show optional accessories.
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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Marco Dropouts

For the Right Amount of Adjustment

Proper chain tension on a hub gear in horizontal dropouts, when it’s also fitted with disc brakes, is an interesting engineering issue. We solved it with Marco dropouts, with integrated, adjustable chain tensioners and tunable disc caliper positioning. Custom CNC machined.

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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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Andros Stem

Adjust to Fit

The Andros is a patented, adjustable stem that lets you adjust your handlebars to the way you want to ride. Easily set the bars low and far for more aggressive riding or higher and closer for a more relaxed position. The Andros makes it simple to adapt a bike for different riders.

Adjusting is simple and can be done with just one hand. Release the safety latch and open the Andros to change the stem and handlebar angle simultaneously. It takes only seconds to get the right position.

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Ergon BioKork Grips

Sustainable Comfort

Ergon grips deliver the ultimate in ergonomics for the hand, reducing fatigue and numbness, even on the longest rides. Ergon’s grips are made from a newly developed BioKork material using 40% cork, sourced from certified, sustainable forests in Portugal. In addition, the inner core is plastic reinforced using natural fibre, which makes up 40% of its mass. In place of mineral oil, the gel in the palm section of the grip is vegetable-oil based.

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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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BioLogic Joule 3 Dynamo Hub

Make Your Own Juice

The Joule 3 is one of the lightest, smallest dynamo hub on the market and is one of only a handful that exceed the High Efficiency (HE) 70% threshold. That means more power at a given speed for brighter lights or for charging devices on your bike while you ride. Most other dynamo hubs have much lower efficiency; the lower the efficiency, the more drag you feel when you’re riding.

The Joule 3 is so efficient, that you’ll hardly notice it’s there, even as you’re using it to power your lights or charge your phone.

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Schwalbe Big Apple Tires

Big and Cushy

There’s an unfortunate misconception that wide, large volume tires are slow and inefficient. We were guilty of this ourselves the first time our Swiss and German product guys recommended we try the Big Apple’s. But then we rode the tires and fell in love. As you might expect, the Big Apple’s are super plush and give a great feeling of security on streets where potholes, train tracks, and drainage gates are the norm. But they are also surprisingly fast and easy rolling. Integrated puncture protection and reflective sidewalls add to urban functionality.

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Shimano Alfine 11 Drivetrain

Shifting Refined

The Alfine 11 hub is a masterpiece of engineering. 11 evenly and widely spaced gears are enclosed in the rear hub shell and deliver 409% of total gear range. But the hub is much more than this: it’s also very light, coming in even lighter than the already svelte Alfine 8-speed hub, and special needle bearings are very low in rolling resistance. Shifts (with an XTR style trigger shifter) are butter smooth and can be initiated any time, while you are stomping on the pedals or while you are waiting for the light to turn green.

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BioLogic FreeDrive

Clean and Quiet

The BioLogic FreeDrive encloses the bicycle chain to keep the rider’s clothing protected from grease and dirty spray. The FreeDrive’s ingenious design moves with the chain so it is friction free, unlike with some other chain protection methods. It also reduces chain vibration and noise. With a FreeDrive, you can say goodbye to bulky chainguards and enjoy the looks and cleanliness of a belt drive with the efficiency of a chain drive.

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Luggage Socket

Carry More Stuff

When you need to carry more stuff on your bike, just plug the optional Luggage Truss into the Luggage Socket that’s welded to the head tube of most Tern bikes. The Luggage Truss works with any bag, basket, or rack with a KLICKfix adapter. The benefit of a frame mounted luggage system (as opposed to fork or handlebar mounted) is that it doesn’t adversely affect steering.

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Valo 2

Always at the Ready

Engineered to integrate directly with the Andros stem or the Syntace VRO 47 stem used on many Tern bicycles, the Valo 2 is a powerful hub-dynamo powered light designed to help you navigate safely at night. It is optimally positioned for visibility and well protected from accidental knocks and bumps, as well as theft. Clarity™ optics project the type of wide, even beam pattern that a cyclist needs - no more lighting the tops of trees or narrowly focused hotspots.

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Cargo Rack

Load 'Er Up

The Cargo Rack is a robust rear rack for hauling large loads. Constructed with thick-gauge aluminum tubing using an ultra-rigid DoubleTruss™ design, the rack supports it all – full-sized panniers on upper or lower rails and KLICKfix™ Rackpack compatible baskets and trunk bags on the top deck. The unique SideStrap™ anti-roll bungee system keeps cargo on the top deck tied down securely. Fully adjustable upper and lower stays allow you keep the rack low and sleek when you’re tooling around town and up high when for when you’re touring with full-sized panniers.

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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
Wheel Size: 24 inch wheels
Speeds: 11
Weight: 15.2 kg (33.5 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: 27" - 109"
Distance: Seatpost to Handlebar: Min: 570 mm (22.4") Max: 730 mm (28.7")
Distance: Saddle to Pedal: Min: 755 mm (29.7") Max: 1030 mm (40.6")
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: Andros, adjustable, patented technology, Norglide bearings
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 GP1 BioKork
Saddle: Kore Sola for Tern, hollow cro-mo rails
Seatpost: Stasis by Syntace, 7050-AL
Seatpost Clamp: Syntace OverLock
Front Brake: Avid DB3, hydraulic disc
Rear Brake: Avid DB3, hydraulic disc
Brake Levers: Avid DB3
Brake Cable & Housing: Avid DB3
Front Hub: BioLogic Joule 3 dynamo, disc
Rear Hub: Shimano Alfine, 11-speed
Spokes and Nipples: Double-butted 18/10 stainless, Sapim Polyax nipples
Rims: Kinetix Comp, mirror finish
Tires: Schwalbe Big Apple 50-507, LiteSkin sidewall, RaceGuard puncture protection, Reflex
Shifter(s): Shimano Alfine, 11 spd.
Crankset: FSA Gossamer custom for Tern, MegaExo, 38T, CNC Guard
Cassette/Freewheel: Shimano for hub gear
Bottom Bracket: FSA MegaExo
Chain: RustBlock, GST coated
Pedals: MKS EZY QR
Shifter Cable & Housing: Shimano
Bell: Dulcet, brass
Chainguard: BioLogic FreeDrive
Kickstand: Premium single, aluminum
Clip System: Magnetix 2.0
Luggage Socket: Yes
Front Light: Valo 2, 41 lux/150 lumens
Rear Light: Spanninga Premium, Dynamo LED with Standlight
Fenders: SKS Aluflex PET, stainless hardware
Rack(s): Cargo Rack
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.

Folding Bikes
October 16, 2012

"Overall, the Tern Eclipse P9 folding bicycle rides like a dream on the street, with the 24” wheels rolling over the bumps and crevices with ease. With its range of gears you’ll be able to ride up bridges and hills during your commute, or carry some groceries home from the store. At the end of your ride, fold up the bike and stow it away. The Tern Eclipse is a great blend of comfort and portability."

Read the full article online here.
July 2, 2012

"And when it comes to handling, the Eclipse S11i is on a class of its own. The bike’s Andros steering system is solid and responsive. I tried the bike on three different kinds of riding: short and middle distance commutes, long-distance day tour – and I am happy to report that all had turned out really smooth."

Read the full article online here.

June 29, 2012

"Das Tern ist die eierlegende Wollmilchsau, die sich wirklich fährt wie ein großes Rad. Größere Laufräder und ein etwas größeres Faltmaß bringen beim Tern ein vielfaches an Fahrfreude an einem rundum gelungenen Rad. RADtouren Kauftipp!"

June 27, 2012

"Was die Eclipse-Serie von Tern auszeichnet, ist unseres Erachtens vor allem das Fahrverhalten: Die um zehn Zentimeter größeren Durchmesser im Vergleich zu den üblichen 20 Zoll-Rädern stabilisieren durch ihre höheren Kreiselkräfte die Fahrt, sie loten mit ihrem größeren Radius nicht jede Plattenfuge aus, und sie verkürzen Dank des höheren Rahmens den Überstand von Sattelstütze und Lenksäule. Diese werden dadurch wesentlich steifer. Zudem hat Tern gegenüber früheren Dahon-Modellen die Rahmen komplett überarbeitet und mit deutlich größeren Faltscharnieren versehen. Wiegetritt, einhändiges oder gar freihändiges Fahren – unterm Strich fährt sich das Eclipse P9 fast so, als sei es kein Faltrad."

The active Times BETA
May 18, 2012

"The Tern’s larger wheels and stout frame take it in stride, and feel quite comfortable at speed, too. The double-braced, fully adjustable stem, in particular, gave this bike the most assured front-end stiffness of the bunch — plus it’s a great feature for fitting riders of varying sizes."

Read the full article online here.

April 16, 2012

"The Tern Eclipse S11i is one of the most well conceived folding bicycles from Tern. It has more features than any other Tern bike: dynamo lights, hydraulic disc brakes, rack, fenders, adjustable handlebar, and the list goes on! If you want the best of the best folding bikes from Tern the Eclipse S11i is the one for you."

Watch the full video review of the Eclipse S11i.

The Gear Caster
November 5, 2011

"So you got a folding bike, you can just go in (to the ferry) and sit down. So while everybody kinda has their bikes deck on each other. You can just hang out and have your bike next to you for the next ride. This is pretty cool."

Read the full article online here.

RADtouren Magazin
October 18, 2011

"Ebenfalls auf der Eurobike nahm die Redaktion des Magazins RADtouren auf dem 24″ TERN Eclipse S11i Platz. Das überaus positive Fazit des Kurz-Checks."