Breaking Away: BMW “R100STR” Scrambler

Xavi Dynamische’s BMW R 12 G/S-inspired Airhead…  

In recent years, we’ve seen a ton of BMW airheads customized along similar lines: retro flat or tractor seats, black-painted engines, minimalist finishes, and vintage scrambler or café racer handlebars. Our friend Xavi Dynamische wanted to break away from that style. 

“Many of those bikes are beautiful and the formula works very well. But personally, I was becoming tired of seeing the same type of customization over and over again. Too many of the bikes were beginning to look almost identical. So with this R100R, I wanted to do exactly the opposite.” -Xavi

Instead of the café racers and scramblers of the 1960s, Xavi looked to more modern platforms for his inspiration. Specifically, the BMW R 12 G/S and Triumph Scrambler 1200 XE. 

“I wanted something with that kind of presence: tall, purposeful, and roughly fifty percent road bike and fifty percent off-road-inspired machine. Above all, I wanted it to be fun.”

So Xavi turned the bike into a machine that blends that kind of stance and all-terrain utility with an unpainted engine that retains its patina and vintage appeal.  The resulting machine is a cross between the modern and vintage, with nods to the Marlboro-liveried Dakar bikes and white-painted G/S machines of yesteryear.

“What I’m trying to achieve is a motorcycle that still has a few vintage touches, but where most of the components and design details have a modern appearance. I wanted somebody to look at the engine and immediately recognise that it is an old BMW boxer, but then look at the rest of the motorcycle and feel that it appears much newer. That slightly unusual contrast was very intentional.”

We absolutely love this build, and the way it departs from the airheads that so often show up in the custom world. With this “R100STR,” we have the best of both worlds: vintage charisma and patina matched with a big, modern presence. Below, Xavi gives us the full story of all the changes — both subtle and major — that brought this build to life.

In the Builder’s Words…

As you know, it’s a BMW R100R. It belongs to the final generation of carbureted boxer motorcycles built by BMW before the arrival of the four-valve boxer engines and the Telelever front suspension. This model already came with BMW’s Paralever rear suspension and shaft-drive system.

Throughout my life, I’ve owned almost every kind of BMW boxer. At one point or another, I’ve had air-cooled, water-cooled and oil-cooled: R65, R80, R1100GS, HP2 MM, R1200GS, R1200GS LC etc. I’m definitely a BMW enthusiast. I’ve always loved the brand, but strangely enough, I had never owned this particular model.

I originally went to test this bike for a client who was thinking about buying an R100R. In the end, the client decided that he didn’t want it, but after riding it, I simply couldn’t resist buying it myself. Honestly, I couldn’t avoid it.

The bike felt incredibly refined for an old boxer. It was smooth, elegant and extremely well balanced. It was also completely standard and in very good condition. I bought it without really knowing what I was going to do with it. I wasn’t sure whether I would customize it or eventually sell it. In fact, I advertised it for sale for a while because I wasn’t using it very much. But in the end, I decided to keep it and build something with it. That raised the main question: what exactly could I do with an R100R?

For roughly the last ten years, we’ve seen the same style applied to many classic BMW boxers: vintage seats, retro fenders, café-racer or scrambler styling, old-fashioned exhaust systems, engines painted black, frames painted black and very clean, minimal finishes. There’s nothing wrong with that style. Many of those bikes are beautiful and the formula works very well. But personally, I was becoming tired of seeing the same type of customization over and over again. Too many of the bikes were beginning to look almost identical. So with this R100R, I wanted to do exactly the opposite.

I painted the frame white, inspired by some of the old Dakar BMW GS race bikes and the Marlboro-liveried GS models that used white frames. Instead of fitting a flat vintage seat, I installed a much more contemporary seat. It comes from a Honda CBF250 from around 2018.

The rear tail section also rises upwards because I wanted the bike to have a more aggressive, modern-looking rear end. The tail section itself was made at home from a sheet of plastic that we shaped and bent using heat. It also incorporates the licence plate mounting.

The exhaust follows the same philosophy. I could have fitted a traditional reverse-cone silencer, a SuperTrapp or another vintage-style exhaust, but I deliberately chose not to. Instead, I fitted a modern carbon-fibre silencer with titanium end caps. It is very light and it sounds excellent.

The engine is another important part of the concept. The obvious approach would have been to dismantle it, paint everything black and make it look completely restored, immaculate and almost brand-new. But I didn’t want that. I wanted to preserve the engine exactly as it is, with its natural aluminium finish and even some of its age-related oxidation marks.

It has been thoroughly cleaned and mechanically inspected. We have serviced the engine, replaced and checked some gaskets and rebuilt and adjusted the carburettors. Mechanically, the motorcycle runs perfectly. But visually, I wanted to retain the original colour and character of the BMW aluminium. I didn’t want this to look like a flawless, high-budget show bike. This is a home-built custom motorcycle, created with a lot of care and many hours of work, but without an excessive budget.

At the front, instead of using a traditional vintage fender, we installed a high front fender from a modern AJP enduro bike. It has sharp and aggressive lines. That modern fender is combined with a round headlight and a small screen that hides the instruments and electrical components. The round headlight and small screen are probably the most traditionally scrambler-inspired elements on the bike. It also has a BMW GS handlebar from the 1990s.

For the handguards, I again chose a modern solution. The bike has Barkbusters rather than old-fashioned hand protectors. The mirrors are also contemporary. They are adjustable aluminium mirrors with carbon-fibre inserts.

What I’m trying to achieve is a motorcycle that still has a few vintage touches, but where most of the components and design details have a modern appearance. I wanted somebody to look at the engine and immediately recognise that it is an old BMW boxer, but then look at the rest of the motorcycle and feel that it appears much newer. That slightly unusual contrast was very intentional.

There are two modern motorcycles that clearly inspired this project. The first is the new BMW R 12 G/S. The second is the Triumph Scrambler 1200 XE, which is another motorcycle that I really like. I wanted something with that kind of presence: tall, purposeful, and roughly fifty percent road bike and fifty percent off-road-inspired machine. Above all, I wanted it to be fun.

To make the bike more entertaining and responsive, we also changed its geometry. At the rear, we installed an adjustable White Power shock from an R100GS. It is approximately two centimetres longer than the standard R100R shock. The original shock measures around 47.5 centimetres, while the GS unit measures approximately 49.5 centimetres.

At the front, we raised the fork tubes through the triple clamps by around 2.4 centimetres. This gives the motorcycle a much more forward-leaning and purposeful stance. It also improves its behaviour on asphalt. The bike turns more quickly, feels more reactive and is more enjoyable through corners. However, the suspension remains relatively soft, so the motorcycle still retains the smoothness and elegance that are so characteristic of the R100R.

Regarding the paintwork, the frame is white because I wanted it to act as a visual frame around the boxer engine. I wanted the engine to remain the centrepiece of the motorcycle and to be clearly visible inside that white structure. The rest of the bike uses a combination of satin white and satin black, with a few small red details. We also added some Marlboro graphics as a subtle tribute to the enormous BMW GS rally bikes that competed in the Dakar with full Marlboro liveries. It is only a reference. I didn’t want to copy the typical red-and-white Marlboro GS paint scheme because that would have been the obvious solution.

The main theme of this motorcycle has always been to break away from the traditional vintage BMW scrambler formula. Just because a motorcycle has an old boxer engine doesn’t mean it automatically needs a brown flat seat, knobbly tyres, clip-on handlebars, a black engine, a black exhaust and a black frame. Everything doesn’t need to be dark, minimal and inspired by the 1960s. Instead, I wanted to move the visual reference point forward by a few decades, towards the 1980s and 1990s.

After all, this is not a motorcycle from the 1960s. It’s a BMW from the early 1990s, built just before the major transition to BMW’s four-valve boxer generation. So rather than making it look older than it really is, I wanted to reinterpret it as something more contemporary, brighter and more playful. The idea was to bring some white and some light back into the custom-bike world. That, ultimately, is the philosophy behind the entire project.

Follow the Builder

Instagram: @xavi_dynamische
Xavi’s business partner and welder: @francolinerr

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