JAX Garage builds an aggressive Airhead…
BMW Airheads may have covered more miles in more different countries than any other European motorbike. They were once the go-to machine for two-wheeled circumnavigators, and they proved themselves in arenas as far-ranging as the Paris Dakar Rally, Baja 1000, and AMA Superbike.
In recent years, these old air-cooled flat-twins have found themselves in the limelight once again, not only as design inspiration for machines like BMW’s own 1800cc R 18, but as foundations for custom builds from all over the world.
The ’83 R100 you see here comes by way of Melbourne’s JAX Garage, a small family-run workshop that specializes in vintage BMW (R and K series) and Honda (CB and CX series) builds, as well as custom parts, fabrication, and engineering solutions.
This R100 was built for the owner of an adventure-touring company based in Australia’s Victorian Alps, aka the High Country. He had two main criteria for the build: He wanted a bobber with sport influence, and he wanted it to be Satin Papaya Orange — the color of the McLaren F1 team.
Given that the owner is used to stand-up adventure riding, the JAX Garage team decided to go above and beyond a regular bobber build to forumulate a machine that would truly excite such a rider:
“We didn’t want to create another R-series bobber. We knew the customer liked adventure riding, so we spent considerable time to make this right, and it paid-up big in the end when it was completed. Hence why we call it a Sport Bobber.”
Highlights include upside-down GSX-R forks mounted with JAX Garage’s own Fork Conversion Riser Kit, as well as larger 310mm brake discs and fully adjustable YSS shocks for the rear. The seat is higher than most bobber builds for more aggressive riding, mounted on a custom fabricated chromoly subframe, and the bike is running a full suite of German-made motogadget electronics with a custom loom.
The bike now inhales through a set of Mikuni flat-slide carbs, and the bike is covered in small custom-machined items like the engine breather and oil cooler cover:
“Don’t ask how many hours we spent on small items like this, but when you get sucked down that custom-machined rabbit hole it’s hard to get out of it.”
While headman Jas isn’t sure the new carbs really translate to 25% more power, as Mikuni claims, he says the bike definitely packs a harder punch:
“The 30kg weight saving also means this R100 is considerably lighter than what it was — coupled with the improved power, it pulls exceptionally well for a 40-year-old bike.”
While some custom bikes ended up sitting in garages or even living rooms, the new owner has been putting this R100 “Sport Bobber” through its paces both on road and off:
“Within the first week he added close to 800km on it. Guess he couldn’t get off it, which is always a good thing to hear.”
Below, we talk to headman Jas Babalija for the full story behind this R100 custom.
BMW R100 Sport Bobber: Builder Interview
• Please tell us a bit about yourself, your history with motorcycles, and your workshop.
JAX Garage was officially created in early 2019 by Jas Babalija, the founder, engineer, and builder. It was created to scratch a personal itch; that is, pursuing a creative outlet.
The team also consists of two others: Dom Scarpari, a Motor Mechanic by qualification with over 30 years’ experience and a wealth of knowledge in custom machining, and our Creative Director, Christina Babalija, who captures all the work we do.
We’re not just any Melbourne-based custom motorcycle workshop. As a team and a family, we do 3 things:
- We create custom motorcycles.
- We offer custom parts (JAX Garage Original range, motogadget, Rick’s Electrics, Highsider, YSS Custom Shocks).
- We offer fabrication and engineering solutions.
We’re firm believers that anyone can build a truly great custom motorcycle as long as they’re not afraid to make some mistakes and get their hands dirty.
Note that we specialise in BMW K and R bikes, and vintage Hondas (CB’s and CX’s).
• What’s the make, model, and year of the donor bike?
1983 BMW R100.
• Why was this bike built?
Customer project — they asked for a Bobber crossed with something more sporty. So we coined it a Sport Bobber as it sits more aggressively than most bobbers, has a higher seat, as well as front and rear shock upgrades for a better ride. It also boasts new tech wherever you look, but with an old-school look and feel.
• What was the design concept and what influenced the build?
The customer provided us with a significant amount of creative freedom. Two criteria had to be fulfilled.
- It had to be a bobber.
- It had to be Orange (Satin Papaya Orange, to be exact — McLaren F1 team inspired).
We sorted out the rest, and kept the color scheme to only two additional colours (black and silver / polished finishes). This gives a mix of old-school and new-school with the bold Papaya Orange, which is what we’re all about.
• What custom work was done to the bike?
1. Complete front-end change: JAX Garage Fork Conversion Riser Kit with 2007 Suzuki GSXR forks, a custom brake rotor adapter kit to suit the original front wheel but with bigger brake discs (310mm). The bike now handles and stops fantastically.
2. Fitted out with motogadget electrics and ground-up wiring loom (there’s a complete wiring diagram available for this bike on our blog page), switchgear, Bluetooth compatibility (the whole lot, really — we’re motogadget dealers, and love their products so it makes sense for us to walk the talk when it comes to fitting parts).
3. Custom chromoly steel subframe to accommodate the bobber seat — but at a higher elevation for a more aggressive stance and seating position. (The customer is used to standing up on pegs and riding road-trail bikes in the Victorian High Country — hence the company logo on the tank advertising his motorbike tour company.)
4. YSS Bobber shock upgrade housing custom YSS shocks RG-CB-362-TRCL in a Naranga Orange colour scheme to tie in the rest. The customer now gets pre-load, length, rebound, and compression adjustment at a dial.
5. Aftermarket exhaust system with shorty mufflers fitted.
6. The purists will hate is even further, but we ditched the airbox and the original Bing Carbs and fitted Mikuni flat slides for an additional 25% power.
7. Considerable adjustments to the centre-stand and ride-height of the bike with the new suspension fitted.
8. Plenty more other smaller features like a custom billet engine breather that we made on our lathe + mill — don’t ask how many hours we spent on small items like this, but when you get sucked down that custom-machined rabbit hole it’s hard to get out of it. We also made an ornamental aluminum cover for the oil breather (because the oil breather looks very much out of place on the 80’s R100s).
• Does the bike have a nickname?
We simply call it our BMW R100 Sport Bobber build.
• Any idea of horsepower, weight, and/or performance numbers?
It hasn’t been dyno tested, and we don’t quite believe the 25% power upgrade claims that Mikuni make, but it definitely packs more of a punch than it used to. The 30kg weight saving also means this R100 is considerably lighter than what it was — coupled with the improved power, it pulls exceptionally well for a 40-year-old bike.
• Can you tell us what it’s like to ride this bike?
We never got to utilize the road-trail aggressive tyres off-road, so we never got to put the bike through its paces. But the owner sure has. This bike has since gone to the owner, and within the first week he added close to 800km on it. Guess he couldn’t get off it, which is always a good thing to hear.
• Was there anything done during this build that you are particularly proud of?
The stance, simplistic look and ride that we achieved. We didn’t want to create another R-series bobber. We knew the customer liked adventure riding, so we spent considerable time to make this right, and it paid-up big in the end when it was completed. Hence why we call it a Sport Bobber.