Fuller Moto’s custom BMW R18 is inspired by the iconic R5

When Bryan Fuller learned that BMW had secretly sent prototype 1,800 cc engines to a handful of custom builders ahead of the BMW R18’s release, he went straight into imagination mode. The founder of Fuller Moto couldn’t get the big boxer out of his mind—so when he was finally approached to build a custom R18, you’d better believe he was on board.

The original BMW R18 concept bike was heavily inspired by the BMW R5—a bike that Bryan has been lucky enough to study closely. But when the R18 finally hit the market, it had grown considerably in size.

Once you get the mammoth power cruiser off the line, the weight magically disappears and it’s a total hoot to ride. Nevertheless, the the fact that it has a reverse gear speaks volumes. Bryan wanted to address the neutron star-like mass of the thing, and bring back some of that vintage R5 charm.

With a fresh BMW R18 on the bench at their workshop in Georgia, USA, Fuller Moto set to work. The team started by removing the airbox, only to find that the R18 had direct injection.

Figuring out a way around the numerous sensors would have taken weeks. Instead, the whole system—from the wiring to the intakes and even the ABS traction control setup—was ripped out. “When in doubt, no need to fret—just grip and rip,” Bryan quips.

“The amount of weight removed, I’m guessing, was around 250 pounds [113 kg]. We removed two large moving boxes worth of stuff.”

With the weight down and a bare chassis and engine waiting patiently, Bryan unleashed his artistic side. “In the back of my mind was the Nigel Petrie [Engineered to Slide] BMW R nineT chopper I saw, courtesy of BMW USA at the Barber Vintage Festival a couple of years ago,” he explains. “It was an incredible mix of high-end fabrication and old-school chopper lineage. He just killed it on that bike.”

Bryan also set out to use a set of 23” wheels to drive home the old-school nature of the build. Custom steel rims were laced to the stock BMW hubs with stainless spokes, and the swingarm was extended to allow the larger-diameter wheels to fit. A Fox rear shock was bolted on, and all the brakes were upgraded with purpose-built Beringer components.

Next on the agenda was the bodywork. A set of recycled fender blanks were trimmed and massaged into shape, supported by custom chromoly braces, all built to mirror the original BMW R5. The team did an incredible job of making such large pieces of metal look fine and delicate (take note of the tasteful lip welded onto the edge of each fender).

The tank is from an original BMW R5. The front mounting tabs were (amazingly) an exact fit for the modern R18 frame, but the bottom of the tank had to be trimmed and made to fit the backbone.

A custom solo saddle was made too, inspired by the Denfeld seats of old. The rear rack and license plate holder are both custom items. The headlight is OEM, but Bryan gutted it and installed a simple H4 globe to light the way, along with a vintage-style lens.

With the rest of the bike taking shape, attention was turned to the BMW’s beating heart.

“One of the highlights of Nigel’s BMW chopper is the Morris Magneto ignition he adapted from traditional Harley applications,” says Bryan. “Nigel was nice enough to take the time out of his Australian fabrication shop activities to answer some of my questions about adapting this type of unit. Shockingly, Nigel said it was pretty easy!”

The Morris Magneto is mounted at the top of the engine, right at the front, above the timing cover. It’s driven by a belt (using Ducati belt tensioners), which spins a magnet inside a field of windings. The magneto acts very much like a car alternator. That, paired with a very vintage Morris points setup, is how the spark plugs get their power and the ignition timing is set. It also looks bloody awesome.

With the engine breathing through a custom airbox, mated to an original round BMW air filter housing, a pair of 40 mm SC2 SmartCarbs hurl fuel down the 3D-printed aluminum intakes. The factory rocker covers were taken off and replaced with a stripped-down Fuller-ized versions. Not only do they save a bit of weight, but they also have a certain mechanical charm to them, giving the cylinders the squared-off look of a classic BMW airhead from the 50s.

A stainless steel exhaust was fabricated and terminated with a pair of Cone Engineering reverse-cone mufflers. Waterjet stainless pieces were added on for even more vintage flair, with a modern twist.

Single-stage black paint was laid over all the bare components, with Bryan’s mate Chastin Brand finishing it off with pin-striping and silver leaf. In case you miss them, there are even tiny LED turn signals mounted on the fenders at each corner.

“I’m particularly proud of this bike, it really lives up to the vision I had in my head,” says a beaming Bryan. “Classic lines, comfortable, powerful, and only what it needs to help the owner spend a great day in freedom.”

Fuller Moto has stripped this BMW R18 behemoth down to its core components, and it looks all the better for it. The combination of skinny tires, a huge engine and classic lines is certainly a formula for success.

There’s just one thing it might struggle with; traction. We’re sure Bryan won’t be complaining, though.

Fuller Moto | Facebook | Instagram | Images by Steve West