100th Anniversary Airhead: BMW R100 Special

100th Anniversary R100 from Bolt Motor Co… 

The BMW R100 is the 1000cc version of the beloved “airhead” machine. Over the years, these flat-twin engines have become nothing short of iconic. They last forever, can be worked on with basic hand tools, have plenty of low-down grunt, and will run forever at speeds in excess of 75 mph. They are likely the most recognizable motorcycle engines in existence.

Two-valve boxers have been the basis for everything from early AMA superbikes (hello Butler & Smith) to new-fangled “Enduroboxers” to mile-eating Iron Butt superstars.

“The flat twins have a very low center of gravity, making it a pleasure to maneuver in any situation… Where it reveled was on long distance, two lane highways, such as British Columbia’s highway 97C through the Okanagan Valley. The huge gas tank meant a range of 400 km, and I often drained it without a stop. Doing that on my RZ350 would mean a month of traction!” –Curbside Classics

The 1000cc airheads also make great candidates for customization. In fact, we see so many custom boxers come our way it’s easy to get a little jaded…until you see one that breaks the mold, showing you something you’ve never seen before. That was the case with “Elvira,” the Wolfsmiths R100/7 we featured earlier this week. And it’s the same with this R100 from our friends at Spain’s Bolt Motor Co.

The Bolt team has a background in professional racing, which shines through this build, both in terms of the aesthetics and performance updates. The customer who commissioned the build brought in the donor with thousands of miles on the odometer and years’ worth of neglect — the perfect candidate for a “neoclassic” transformation.

The team gives us the full rundown of the upgrades below. Highlights include Marzocchi forks, Brembo brakes, Motogadget lighting and electronics, rebuilt engine with tuned carbs and exhaust, rain-resistant suede saddle with matching embroidery elsewhere on the bike, and one very trick dual-use tail section that switches between a monoposto and two-seater in seconds. 

The paint is a tribute to the 100th anniversary of BMW Motorrad, founded in 1923. All in all, this is one bold and beautiful R100 that would surely have the original BMW engineers shaking their heads at how far the old airhead engine has come…and how beloved it remains to this day.

In the Builder’s Words…

New BOLT, new project, new challenge… and a new dream come true.

This is a project we’re especially excited about — based on one of the most iconic models in the world of custom builds: the classic BMW Boxer. We’re about to carry out an exclusive transformation on a bike that was released in several versions, and the personalization we’re applying to it is something very special.

The client brought in the bike with thousands of kilometers on the clock, having spent years neglected and in serious need of some love — just the kind of story that gets the entire BOLT team excited. We love bringing these machines back to life — bikes that were once unique and full of soul.

The briefing we received was detailed and ambitious, but at the same time the client gave us full creative freedom to shape the concept. The goal: to create a special with real character and a bold, one-of-a-kind neoclassic style.

So we started by dissecting the bike.

The client wanted powerful braking and a very secure ride feel. To achieve that, we installed a complete Marzocchi front end and added oversized brake discs with a high-performance Brembo master cylinder and calipers, giving this classic bike exceptional control. The rest of the components were assembled at our workshop — forks, yokes, discs, wheel axle, steering shaft, etc. — with meticulous craftsmanship and top-tier results.

We fitted a super comfortable Renthal enduro handlebar, Biltwell grips, Motogadget bar-end indicators, and stunning Highsider mirrors from Germany. All of this is combined with Motogadget domotic controls and the Pro digital display.

The front end features a next-gen LED headlight with a completely different design aesthetic — bold and unique — mounted on our very own 3D-designed headlight mask, created in-house by BOLT.

Up top, we put a lot of care into the details. The paint was a perfect choice: a tribute to BMW Motorrad’s 90th anniversary, interpreted through the lens of the R100. A truly unique and special design, just like every BOLT build.

The seat is a fully handcrafted piece, made from rain-resistant suede with embroidery matching the tank and side covers. We also installed a dual-mode tail section, 3D-designed and removable: use it as a monoposto or convert it to a two-seater in seconds. Pure craftsmanship.

Electrically, we remapped the ECU and tweaked the engine behavior. The entire electrical system was designed and installed by our engineers, who come from a competition background. We used high-performance wiring and fully reprogrammed all dashboard functions.

Mechanically, the engine was fully restored — every last bolt. Our techs pushed the motor’s potential to the max, refining the carb setup and installing handcrafted Turbokit exhausts. The result is a punchy, torque-heavy engine full of soul and attitude.

In the rear, we restored the original wheel and driveshaft. The license plate holder is a BOLT custom piece, with fully hidden wiring.

The clutch and brake levers are top-of-the-line Nissin components, matching the quality and detail level of this standout build.

This is a truly special BOLT project, crafted with a high level of engineering, design and refinement — a project taken to another level.

A special with unmistakable personality and bold presence. One that will make waves, and — as always — another happy BOLT client, now a friend.

Build Sheet

Base Bike: BMW R100RT
Year: 1982
Engine: BMW
Carburation: BING
Ignition: ELECTRONIC
Clutch: BMW
Flywheel: BMW
Front End: MARZOCCHI
Swingarm: BMW
Brake Calipers: BREMBO
Discs: BREMBO
Brake Lines: GOODRIDGE
Yokes: CNC Custom by BOLT
Fuel Tank: BMW
Headlight Bracket: By BOLT Motor Co.
Subframe: By BOLT Motor Co.
Air Filters: By BOLT Motor Co.
Exhaust: TURBOKIT
Silencer: TURBOKIT
License Plate Holder: By BOLT Motor Co.
Front Fender: By BOLT Motor Co.
Rear Suspension: YSS
Front Light: Husqvarna Next-Gen LED
Tail Light: MOTOGADGET
Indicators: MOTOGADGET
Tyres: METZELER
Electronics: BOLT
Electrical Wiring: By BOLT Motor Co.
Seat: Llop
Paint: Airbrush Custom
Foot Pegs: TAROZZI
Rear Sets: PUIG
Grips: PUIG
Mirrors: HIGHSIDER

Follow the Builder

• Website:  www.boltracer.com
• Instagram @boltmotorcompany
• Facebook: boltmotorcompany
• Photography: Mario Rodrigo Martín

More Bolt Motor Builds

---