Categories
Japanese Road Bikes

TOEI Randonneur: This Week’s Featured Japanese Bicycle

Introducing a Unique Two-Wheeler

By James Hickman — Former USA Cycling Expert Coach, Masters Racer

Quick Answer: This TOEI Randonneur is a custom lugged steel touring bike built on a TOEI Frame B Cut Lug (560mm), finished with a French-influenced component set — Grand Bois cockpit and fenders, a TA Cyclotourist crankset, Huret Jubilee derailleur, and MAFAC Competition centerpull brakes. It’s a working example of how Japanese frame builders adopted and refined the classic French randonneuring formula.

Toei Japanese bicycle Sports Model

This week’s featured bicycle is a TOEI Randonneur — aJapanese Steel classic bicycle design from Japan technically advanced touring build with a detail worth noting up front: it’s the first TOEI Randonneur completed without the long build delays the workshop is known for. The owner specified a French-influenced parts list, and the result shows how a Japanese frame builder interprets a design tradition that originated on the other side of the world.

Frame Construction and Geometry

The frame is a TOEI B Cut Lug, a traditional lugged steel construction sized at 560mm for this build. TOEI’s lugged joints are hand-filed rather than left as cast, a labor-intensive step that’s largely disappeared from production frame building but remains standard practice among Japan’s boutique steel builders.

Toei Japanese bicycle stem and headset
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Steering runs through a Grand Bois Small Vintage headset, chosen for its classic profile, paired with a Tange LN7922 bottom bracket supporting the drivetrain. The stem is a custom TOEI unit built without a cable-routing hole — a small detail that reflects how this build’s cable routing was planned around the rest of the touring kit rather than adapted to a stock part.

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Up front, a Grand Bois French-type handlebar in 420mm width sets the hand position, and a TOEI front carrier (6mm tubing) adds cargo capacity for randonneuring or light touring. A Grand Bois PJ700 mudguard set keeps road spray off the rider — a non-negotiable on a bike built for all-weather distance riding.

Drivetrain Configuration

Toei Japanese bicycle components

Power goes through a TA Cyclotourist crankset — a French-made part with a long history in touring and randonneuring circles, prized for its serviceability and wide gearing range. It’s paired with TA chainrings in a 48×36 setup, giving the rider a meaningful spread between spinning gears for climbing and taller gears for open road.

Shifting is handled by a Huret Jubilee derailleur, one of the lightest and most recognizable French derailleurs of its era. The chain is a Shimano HG71, running against a Shimano Dura-Ace 7400-series freewheel spanning 14-26 teeth across seven speeds. Christophe toe clips and straps complete the pedaling system, working with the crankset to keep the rider’s foot properly positioned over long distances.

Wheels, Tires, and Braking

Toei Japanese bicycle shifters

The wheelset is built around Campagnolo Nuovo Tipo quick-release hubs in 100/126mm spacing, laced to Grand Bois Papillon rims in a 700C, 36-hole configuration. Grand Bois tires in 700x28c width round out the wheel package, striking a balance between rolling resistance and the comfort a randonneur bike needs on rough or unpredictable pavement.

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Braking comes from MAFAC Competition centerpull brakes, a classic French design known for strong stopping power and symmetrical pad wear — a favorite among randonneur builders for decades. Campagnolo brake levers control them from the bars.

Finishing Details and Touring Accessories

Toei Japanese bicycle down tube

The rider sits on an Idéale #90 lightweight saddle, a classic French leather saddle chosen for long-distance comfort. This TOEI Randonneur is fully equipped for after-dark riding, running a dynamo-powered lighting setup with a pin-bulb headlight and a rear taillight, backed by a bottle dynamo for power — no batteries required. A Silca Impero frame pump handles roadside repairs, keeping the bike self-sufficient on longer routes.

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TOEI Brand Context

TOEI is one of Japan’s respected lugged-steel frame builders, working in the same tradition as shops like Cherubim and 3Rensho but with a particular focus on touring and randonneur geometry. Frames like this one reflect a builder-client relationship closer to custom tailoring than production manufacturing — specs are worked out directly with the customer, and turnaround has historically run long, which is part of what makes this particular build notable.

The combination of Japanese frame construction with French componentry (TA, Huret, MAFAC, Idéale, Grand Bois) is a hallmark of serious randonneuring builds worldwide, and this bike is a clean example of that formula executed well.

Frequently Asked Questions

What frame material and construction does the TOEI Randonneur use?

It’s a lugged steel frame — TOEI’s B Cut Lug construction — sized at 560mm for this build. Lugged construction joins tubes with hand-filed lugs rather than direct welding, a traditional technique still used by boutique Japanese frame builders.

Why does this bike use French components on a Japanese frame?

French componentry — TA cranksets, Huret derailleurs, MAFAC brakes, Idéale saddles — has a long history in randonneuring, the French tradition of long-distance, self-supported cycling. Pairing a Japanese-built frame with these parts is a common approach among builders and owners aiming for an authentic randonneur build.

What wheel and tire size does the TOEI Randonneur run?

700C wheels with 700x28c tires, built on Grand Bois Papillon rims and Campagnolo Nuovo Tipo hubs.

Does this bike have lighting for night riding?

Yes. It runs a dynamo-powered lighting system with a front headlight and rear taillight, eliminating the need for batteries — a standard feature on randonneur bikes built for all-conditions, self-supported riding.

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Categories
Japanese Road Bikes

Discovering The Koga Miyata Full Pro-A

Discovering The Koga Miyata Full Pro-A

By James Hickman — Former USA Cycling Expert Coach | Bicycle of the Week: Vintage Japanese Road Bikes

Quick Answer: The Koga Miyata FullPro-A was the Dutch-Japanese brand’s flagship racing model, built for two model years (1984–1985) with a fillet-brazed, double-chromed Hardlite FM-A tubeset and a full Shimano Dura Ace AX aero groupset. It’s one of the most collectible steel racers of the mid-80s aero era.

Koga Miyata full pro

This week’s Japanese Bicycle of the Week is the The Koga Miyata Full Pro-A, the top-of-the-line racing model from a brand built on an unusual partnership: Dutch manufacturing and marketing under Koga, paired with Japanese frame-building and component sourcing through Miyata. That combination is what let Koga Miyata build a genuinely competitive racing bike around Shimano’s parts group at a time when most European pro teams were still riding Campagnolo.

The Full Pro-A sat at the top of the Koga Miyata lineup forJapanese Steel classic bicycle design from Japan the 1984 and 1985 model years only, which is part of why surviving examples are relatively scarce today. It wasn’t a mass-production frame — it was the brand’s technical showcase, built to demonstrate what fillet-brazing, chrome plating, and aerodynamic tube shaping could do for a steel race bike before carbon and monocoque construction existed.

What the “A” in Full Pro-A Stands For

The “A” stands for Aero. Aerodynamics became the dominant engineering trend in road racing in the early 1980s, and Koga Miyata built the FULL PRO-A specifically to compete in that conversation. The frame uses drop-shaped, aerodynamically profiled tubing rather than the round tubes typical of the era’s racing steel, and the whole bike — tube shaping, cable routing, brake and pedal design — was engineered around reducing drag rather than just reducing weight.

This wasn’t marketing dressed up as engineering. Koga Miyata’s own 1984 catalog quantified the aerodynamic gains, and the brand backed the claim by building a nearly identical model, the Aero Miyata, for the export market — evidence this was a deliberate design program, not a one-off show bike.

Koga Miyata

Frame and Construction: Hardlite FM-A Tubing

The Full Pro-A frame is built from Koga Miyata’s Hard lite FM-A triple-butted tubing, fillet-brazed rather than lugged. Fillet brazing lets the builder smooth the joints into continuous, seamless curves — a more labor-intensive process than lugged construction, and one that shows up clearly at the head tube and bottom bracket junctions on a well-preserved example.

Geometry followed what Koga Miyata called Full-Power-Drive: a 55cm seat tube that, combined with the raised foot position of Shimano’s Dyna Drive pedals (more on those below), put the rider’s effective saddle height closer to what you’d expect on a 56cm frame with conventional pedals. It’s a detail that trips up collectors trying to size a Full Pro-A off the seat tube measurement alone.

Fully Chrome-Plated Perfection

The signature visual feature is the double-layer chrome plating over the entire frame — not just the fork and stays, as was common on lugged steel racers of the period, but the full frameset. Chrome plating on a fillet-brazed frame is unforgiving of imperfect joint work, since there’s no paint to hide inconsistencies in the brazing. A clean chrome FullPro-A is as much a statement about the builder’s confidence in the joinery as it is about aesthetics.

Practically, the chrome layer also protects the tubing from corrosion far better than the paint of the era did, which is a real part of why so many surviving FullPro-A frames still present well four decades later.

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Shimano Dura Ace AX: An Aero Groupset Ahead of Its Time

The FullPro-A was built around Shimano’s Dura Ace AX groupset, introduced in the early 1980s as Shimano’s answer to the industry’s aero push. AX componentry reshaped nearly every touchpoint on the bike for reduced drag: an enclosed rear derailleur pulley cage, aero brake levers with internally routed cables, and a crank and brake caliper design that moved away from the exposed, drilled-out look of contemporary Campagnolo and SunTour parts.

AX never became a commercial mainstream success — it was more expensive and more specialized than most riders needed — but it’s become one of the more sought-after group sets among collectors specifically because it represents a genuine engineering dead-end: an ambitious idea that didn’t stick, executed at a very high level.

Koga Miyata

Shimano Dyna Drive Pedals

Paired with the AX group set, the Dyna Drive pedal system moved the pedal axle up under the ball of the foot rather than below it, lowering the rider’s effective foot position by several millimeters. The idea was a more direct line of force from foot to pedal and a slightly lower center of gravity. It required proprietary shoes with recessed cleats, which limited adoption outside of AX-equipped bikes — another example of Shimano experimenting boldly in this era, whether or not the idea caught on long-term.

Saddle and Wheels: The Concor Profile and Wolber Profile 18

Period-correct Full Pro-A builds typically ran a Cinelli Unicanitor Concor saddle — a favorite among professional racers through the early-to-mid 80s for its support and low weight — mounted on Wolber Profile 18 aero rims, which used a rounded rim profile intended to reduce drag at speed, a wheel-design trend that would resurface decades later with modern aero rim shapes.

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Why the Full Pro-A Still Matters to Collectors

The Full Pro-A’s real legacy isn’t that it won races outright — it’s that it captured, in one production bike, the exact moment steel construction and early aerodynamic theory intersected before carbon fiber made most of these solutions obsolete. Fillet-brazed, fully chromed, aero-tubed race bikes built for only two model years don’t turn up often, which is exactly why a clean FullPro-A remains one of the more desirable finds in Japanese vintage road cycling today.

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A Note on This Bike’s Current Build

This particular example stays close to its original 1984/85 catalog spec, with two small deviations worth noting for collectors: it now runs Ritchey tires in place of the original Wolber Record Route tubulars, and Christophe pedal straps in place of the factory Koga Miyata straps. Neither change affects the bike’s authenticity in any meaningful way — they’re the kind of practical, period-appropriate swaps you’d expect on a bike that’s actually been ridden and maintained rather than kept as a static display piece.

Frequently Asked Questions

What years was the Koga Miyata FullPro-A made?

The Full Pro-A was produced for two model years, 1984 and 1985, as the top model in the Koga Miyata racing lineup.

What does the “A” in Full Pro-A stand for?

It stands for Aero. The Full Pro-A was Koga Miyata’s dedicated aerodynamic racing model, built with drop-shaped tubing and an aero-focused Shimano Dura Ace AX group set.

What tubing did Koga Miyata use on the FullPro-A?

The frame uses Koga Miyata’s own Hardlite FM-A triple-butted tubing, fillet-brazed and finished with double-layer chrome plating over the full frameset.

Why did Koga Miyata use Shimano instead of Campagnolo?

Koga Miyata built its bikes in partnership with Japanese manufacturing, and Shimano was the natural component partner. The Dura Ace AX group set also let Koga Miyata differentiate the Full Pro-A with an aero-specific parts group most European brands weren’t offering at the time.

Are Koga Miyata Full Pro-A bikes valuable today?

Well-preserved, catalog-correct examples command strong interest among vintage Japanese and aero-era steel collectors, largely because of the short two-year production run and the labor-intensive fillet-brazed, fully chromed construction.

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Categories
Japanese bicycles

Maruishi Emperor 901-SXR: A Rare Japanese Road Bike Find

Quick Answer:

The Maruishi Emperor is the touring flagship of Maruishi Bicycle, a Japanese manufacturer with roots going back to the 1880s. The Emperor 901-SXR is a rare departure from that touring identity — a road-specific variant built almost entirely around a Sugino SG75 component group, featured once in a 1990 Japanese cycling magazine, and rarely seen since.

Nitto Tsubasa 3 handlebar and stem cockpit on Maruishi Emperor 901-SXR
SPECIAL THANKS TO PEDAL ROOM AND BUILDER YPCHAKREE FOR THE IMAGES AND INFORMATION CONTAINED IN THIS ARTICLE.

Most of what collectors know about Maruishi Bicycle comes fromJapanese Steel classic bicycle design from Japan the brand’s touring lineup. The Emperor name has carried that reputation since the 1970s, built around long-haul comfort, rack mounts, and frames that could carry a loaded rider across Japan without complaint. So when a road-specific Emperor shows up wearing a Sugino house build top to bottom, it’s worth a closer look.

That’s exactly what the Maruishi Emperor 901-SXR is. I haven’t been able to track down another example of this bike anywhere online, and the only documentation I could find traces back to a single magazine feature from 1990. For a Maruishi bicycle this specific, that scarcity is part of the story.

If you’re chasing down a Japanese road bike from this era and you’re not sure what you’re looking at, the model name stamped on the down tube or top tube is usually your fastest path to an answer. Serial numbers help narrow a build year, but they won’t tell you whether you’re holding a touring Emperor or something closer to what’s pictured here. When the spec sheet doesn’t match what you’d expect from the nameplate, that’s usually a sign you’ve found something built outside the standard catalog run.

Maruishi Emperor 901-SXR seat stay crossover
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What Is the Maruishi Emperor?

The Emperor line is Maruishi Bicycle’s longest-running touring nameplate, dating to at least the 1970s. Most Emperor models built their reputation on triple-triangle frame geometry — a French “campeur” style where the seat stays cross over the top tube for extra rigidity under loaded panniers — paired with long wheelbases and rinko-friendly quick-release fittings for train travel. It’s a working bike, designed for distance, not speed.

That context matters because it makes the 901-SXR such an outlier. For the full story on the brand, including serial number identification, see our Maruishi Bicycle guide.

Maruishi Emperor 901-SXR Sugino SG75 crankset and drivetrain
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The Maruishi Emperor 901-SXR — A Different Kind of Emperor

The 901-SXR drops the touring brief entirely. This is a road bike, and a special one. Where most Emperor models from this era mix components from Suntour, Shimano, and Sugino — typical for Japanese builds of the period — the 901-SXR is built almost entirely from a single Sugino SG75 group. That’s an unusual choice for any Maruishi bicycle of this era, let alone one wearing the brand’s touring flagship name.

Sugino SG75 rear derailleur on Maruishi Emperor 901-SXR
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Frame and Build

The drivetrain runs Sugino SG75 throughout: crankset, bottom bracket, pedals, chainring, front and rear derailleurs, and shifters all share the same group designation. The brake calipers and levers are Sugino SG75 as well. Up front, a Nitto Tsubasa 3 handlebar and stem handle the cockpit, paired with a Selle San Marco Rolls saddle and a Sugino carbon seatpost — an exotic touch for a Japanese road bike of this vintage. Wheels are first-generation Aerospokes front and rear, which tells you this build leaned into being noticed.

Selle San Marco Rolls saddle on Maruishi Emperor road bike
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If you’re restoring a road bike from this era yourself, Competitive Cyclist carries a solid range of period-correct components and tools worth checking before you start sourcing parts piecemeal.

Maruishi Eimporer front spoked wheel
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How the Emperor 901-SXR Compares to the Touring Emperor Line

Set the 901-SXR next to a standard Emperor touring model, like the triple-triangle RE-C-A “Camper” built for loaded long-distance riding, and the contrast is sharp, as detailed in this restoration writeup of a Maruishi Emperor RE-C-A. The Camper prioritizes stability and cargo capacity, with a long wheelbase and rack mounts built into the frame from the start. The 901-SXR prioritizes speed and a near-monobrand spec sheet that reads more like a special order than a catalog model. Both wear the Emperor name, but they’re built for different riders entirely — which is part of why this bike stood out enough to earn magazine coverage in the first place. It’s a reminder that even within one model line, a Maruishi bicycle could be built for two completely different jobs.

For saddle and cockpit upgrades on your own vintage build, Competitive Cyclist’s saddle and handlebar selection is a good place to compare modern equivalents to period parts.

Maruishi Emporer reversed mounted rear brake caliper
SPECIAL THANKS TO PEDAL ROOM AND BUILDER YPCHAKREE FOR THE IMAGES AND INFORMATION CONTAINED IN THIS ARTICLE.

Maruishi Bicycle History

Maruishi Bicycle traces its roots to the 1880s, when the company claims to have been the first in Japan to import high-wheel bicycles from England. The brand built its reputation on durable, luggage-bearing bikes and became known for its kangaroo logo, still used in company branding today. According to company lore, the kangaroo mark came from an old British gentleman in a swallow-tailed coat, who looked like a kangaroo riding his bicycle through the field — an odd origin story, but one Maruishi has held onto for over a century.

Maruishi Bicycle also produced shaft-drive models alongside its chain-driven lineup — a detail we covered in depth in our piece on Maruishi’s drive-shaft bicycles. The company hit a rough patch in the mid-2000s before resurfacing under new Chinese ownership, but the Emperor name survived the transition and remains part of the lineup today. That continuity is part of why a find like the 901-SXR matters — it’s a snapshot of what a Maruishi bicycle could be when the brand stepped outside its usual touring playbook.

Frequently Asked Questions

What is the Maruishi Emperor?

The Maruishi Emperor is Maruishi Bicycle’s long-running touring flagship line, in production since at least the 1970s, known for triple-triangle frame geometry and loaded-touring durability.

Is the Maruishi Emperor 901-SXR rare?

Yes. The 901-SXR is a road-specific Emperor variant documented in only one known magazine feature, from 1990, and no other surviving examples have been publicly documented online.

What components came on a Maruishi Emperor 901-SXR?

The 901-SXR was built almost entirely around a Sugino SG75 group — crankset, bottom bracket, pedals, derailleurs, and brakes — with a Nitto Tsubasa 3 cockpit and first-generation Aerospoke wheels.

Is Maruishi still in business today?

Maruishi Bicycle continues to manufacture bikes in Japan, though the company has been owned by Tianjin Fushida Bicycle Co. of China since 2006.

Related Reading


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Categories
Classic Japanese Bicycles

Cherubim Bicycles Air Line: A Handmade Steel Aero Frame Built for the Velodrome

Quick Answer

The Cherubim Air Line is a handmade steel aerodynamic bicycle produced by Tokyo-based Cherubim (Konno Cycle Works), founded in 1965. Designed by second-generation master builder Shinichi Konno, the Air Line eliminates all right angles and hard edges from the frame geometry, replacing them with elongated ellipses and flowing curves intended to minimize aerodynamic drag. It is built for velodrome and hour record competition.

Most handmade steel bicycles are celebrated for their rideJapanese Steel classic bicycle design from Japan quality, their geometry, or the precision of their welds. Among Cherubim bicycles, the Air Line is celebrated for something different: it looks unlike any other bicycle ever built. No right angles. No hard edges. No concession to the conventional diamond frame that has dominated bicycle design for over two centuries. What Shinichi Konno created with the Air Line is a fully rideable machine that also functions as a serious argument about the future of aerodynamic bicycle design.

cherubim bicycles the future of aerodynamic bicycle design
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This week’s Bicycle of the Week profile takes a close look at the Cherubim Air Line — its design philosophy, the engineering decisions behind it, and the six-decade history of the workshop that produced it.

The History of Cherubim Bicycles

Cherubim bicycles trace their origin to 1965, when Hitoshi Konno founded the company in what was then a virtually nonexistent custom frame building industry in Japan. According to Subsequence Magazine, the company started out as a garage brand in the most literal sense, but within three years a track bike made by Hitoshi in his tiny workshop had debuted at the 1968 Mexico City Olympics and set a new Japanese national record. That result — just three years after founding — established Cherubim as synonymous with the highest level of Japanese frame building.

Cherubim bicycles synonymous with the highest level of Japanese frame building
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The name itself carries meaning. The brand name Cherubim was chosen by Hitoshi’s mother, a Christian, and the angelic name was intended to give wings not only to the riders of Cherubim bicycles but to their family members as well. Hitoshi’s approach to frame building became legendary within the industry. Industry insiders referred to his passionate approach as “welding mania,” as he continued to churn out novel ideas and revolutionary designs throughout his career.

The Konno family’s influence on Japanese frame building extended beyond Cherubim. Three Konno brothers and their frames — Cherubim, 3Rensho, and Miyuki — led the early age of the frame building industry in Japan. Cherubim is the only surviving brand carrying the family tradition forward. Cherubim bicycles also won seven consecutive Best Handmade Bicycle Awards from 1998 to 2005 at the prestigious annual show sponsored by the Japan Cycling Association.

Cherubim bicycles Awards from 1998 to 2005 at the prestigious annual show sponsored by the Japan Cycling Association
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After Hitoshi retired, his son Shinichi Konno took over. Shinichi operates from the belief that the best bike is a custom steel frame that can be adapted to the rider’s physique, riding style, and preferences — creating bikes of functional beauty that combine the best ride with a shape that appeals to the rider at a high level, without being bound by existing ideas. Today Cherubim operates from a workshop in Machida, a suburb of Tokyo, producing made-to-order chromoly steel frames one at a time.

The Air Line: Design Philosophy

The Cherubim Air Line is not a production bicycle. It is a concept machine, built to challenge the foundational assumption that a bicycle frame must consist of straight tubes joined at angles. Every element of the Air Line’s design flows from a single aerodynamic principle: eliminate anything that creates a hard edge against moving air.

As reported by Designboom, the Air Line’s minimalist form is designed to avoid the right angles and hard edges that cause air resistance in conventional bicycles. Instead it rides on undulating lines and elongated ellipses — a frame geometry that draws more from fluid dynamics than from traditional bicycle engineering. The result is a machine that appears to have been shaped by wind rather than built by hand.

Cherubim bicycles a frame geometry that draws more from fluid dynamics than from traditional bicycle
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The frame is finished in a deep red coat with chrome accents. There are no visible welds in the conventional sense — the transitions between tubes dissolve into curves, making it genuinely difficult to identify where one structural element ends and another begins. The Air Line features an integrated electrical shifting system and 31.8 steel seat tubing, permitting the rider to maneuver efficiently while the low wind drag allows for optimal speed.

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What Konno Set Out to Solve

Shinichi Konno has been direct about the engineering problem the Air Line was built to address. The conventional diamond frame — a design with over 200 years of documented history — is structurally efficient but aerodynamically compromised. Every junction, every tube angle, every abrupt transition creates turbulence. For road racing in a peloton, that drag is manageable. For solo events like the hour record or velodrome time trials, it represents a measurable and addressable performance loss.

Konno’s position on this is unambiguous. In his own words: “Aerodynamics is the largest theme in bicycle history all the time. Cherubim created this bike by breaking the regulations and traditional concepts, because we believe this is the only way to expand the horizon of bicycle design. We’re too wedded to the traditional diamond-shaped bike. Air Line presents the new possibility for the race like the hour record and velodrome time trials.”

This is not a decorative claim. The UCI’s regulations for competitive cycling prohibit many frame designs that deviate significantly from the traditional diamond shape — which is precisely the point. Konno built the Air Line outside those constraints intentionally, as an exploration of what is physically possible when regulations are removed from the design process. The resulting machine is as much a research object as it is a bicycle.

Cherubim bicycles Despite its unconventional appearance, the Air Line is built using the same fundamental material that defines all Cherubim bicycles
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Construction and Materials

Despite its unconventional appearance, the Air Line is built using the same fundamental material that defines all Cherubim bicycles in production: chromoly steel. All Cherubim frames are made from chromoly steel, a special alloy composed of chromium and molybdenum. In contrast to more common carbon or alloy frames, individually hand-welded chromoly tube frames require a high level of skill to produce, and are becoming scarce even in European ateliers.

Chromoly is a deliberate choice for Konno, not a compromise. The material’s properties — its elasticity, its ability to be formed into complex shapes, its response to skilled welding — make it uniquely suited to the organic geometries the Air Line demands. Carbon fiber, while lighter, does not bend and flow the way chromoly can under the hands of a skilled builder. The Air Line could not exist as a carbon frame.

Cherubim bicycles are made to order. Based on a rider’s height and cycling needs, a builder will assemble the frame to exacting specifications. The workshop in Machida operates with a small team, and the hand-built works of Cherubim bicycles have won numerous international accolades including awards from the Hand Made Cycle Fair in Japan and the North American Handmade Bicycle Show (NAHBS).

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The Air Line in Context

The Air Line did not emerge in isolation. Shinichi Konno has a history of producing experimental frames that challenge conventional geometry while competing alongside his mainstream chromoly production work. His Silver Flyer track bike won both Best in Show and the President’s Choice award at the North American Handmade Bicycle Show. The Air Line represents a continuation of that same experimental impulse taken further — to the point where the frame no longer resembles a bicycle in any conventional sense.

What separates the Air Line from purely aesthetic bicycle art projects is that it remains functional. It is fitted with real components, real gearing, real contact points. Konno built it to be ridden, not displayed — though it has been displayed extensively and photographed widely since its introduction. The tension between those two identities — art object and race machine — is part of what makes it one of the most discussed frames in contemporary handmade bicycle building.

For collectors and enthusiasts of classic and contemporary Japanese bicycle craftsmanship, the Air Line represents the current outer edge of what Cherubim bicycles’ six-decade tradition of handmade steel frame building has made possible. It is, in both literal and figurative terms, what happens when a master builder stops asking whether something is allowed and starts asking whether it is possible.

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Frequently Asked Questions

Who makes the Cherubim Air Line bicycle?

The Air Line is made by Cherubim, also known as Konno Cycle Works, a handmade steel bicycle workshop based in Machida, Tokyo. It was designed and built by Shinichi Konno, the second-generation master builder who took over the company from his father Hitoshi Konno, who founded Cherubim in 1965.

What makes the Cherubim Air Line different from other bicycles?

The Air Line eliminates all right angles and hard edges from the frame, replacing conventional straight-tube diamond geometry with elongated ellipses and continuous flowing curves. The design is intended to minimize aerodynamic drag for velodrome and hour record competition. It is built from hand-welded chromoly steel and is made entirely by hand in Cherubim’s Tokyo workshop.

Is the Cherubim Air Line a rideable bicycle or a display piece?

It is a fully functional bicycle. Despite its sculptural appearance, the Air Line is fitted with real drivetrain components including an integrated electrical shifting system and is built to be ridden on the velodrome. Shinichi Konno has stated that the bike was designed specifically with the hour record and velodrome time trials in mind, not as a display piece.

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