Enter the R100X | Custom builder turns 1990s BMW R80R into £40,000 stripped-back dirt demon

What happens when you take a humble 1995 BMW R80R, pluck it from retirement and inject 800 hours of unbounded engineering mastery into it?  

The result is what Formula One engineer Ben Norton has dubbed the R100X – a bike which became a poster child of this year’s Bike Shed Moto Show, in London

“Bike building is stress relief for me,” Norton said. “It’s all about getting back to working with my hands.” 

Rear three quarters - photo credit Christopher Bailey

The R100X is his third boxer build, although this one certainly injects a different flavour into the classic Bavarian machine than his two previous builds. 

Whilst his prior offerings have been decidedly street oriented – including a bonkers bored-out, and then supercharged R80, this final machine in his BMW trichotomy is aimed squarely at the dirt. 

Norton describes how his off-road routes growing up in Zimbabwe inspired the R100X: “I’ve always loved watching the Dakar. BMW has such a rich history in desert racing, and I wanted to create a modern take on those old bikes.” 

Right hand side shot - photo credit Christopher Bailey

BMW’s own enduro heritage heavily influenced Norton’s creative pathway, with the engineer adding: “The X designation is me providing a nod to the innovation that BMW applied to the G450X.” 

Starting with the motor, Norton added a 1000cc kit, upping the boxer’s bore from 798cc. Accompanying that are revised gear ratio’s to improve low speed usability, a custom oil sump for improved ground clearance and the whole motor has been pitched up too, again in efforts to improve clearance and accommodate the big 21” front wheel and longer travel fork. Ben also designed his own billet timing and front covers for the engine to shed excessive weight. 

An exposed K&N air filter sits atop a custom mounting plate, with all breather pipes routed through it. This is protected by an extended rear mudguard, which Norton claims to be sufficient to keep dust at bay. A chunky, nearside mounted titanium end can from SC Project is then on hand to deal with exhaust duties. 

Left hand side shot shows the SC project exhaust - photo credit Christopher Bailey

Power is delivered to the 18” Excel rear wheel via a custom drive shaft housed within a modified monolever swingarm lifted from an R100RT. This joins a bespoke aluminium rear hub, which has been engineered to accommodate 36 spokes (rather than the standard 40), whilst also retaining a drum brake set up. All in, the rear hub is responsible for 50 hours of engineering time alone! 

Gone is the original flimsy suspension and in its place, a one-of-one Penske monoshock delivers 225mm of bounce out back, and upfront, beefy 48mm forks lifted from a KTM 690 Enduro offer 250mm of rock swallowing travel. These are connected to a 21” front wheel for maximum off-tarmac potential. 

Bodywork is minimal but no less detail mad than the rest of the build. Simple plastic fenders jut out front and rear, but the tank is the real gem here. Norton has opted for a BMW R65 fuel tank, chosen for its angular nature, which in his words: “creates a strong visual lower line through the seat and to the rear fender.” 

Front three quarters shot of the long legged custom desert racer - photo credit Christopher Bailey

Looks aside, functionality has been meticulously attended to, and off-road, that means stripping mass. A lithium battery has been opted for to provide juice for the bike’s bespoke wiring loom and holding everything together is a lightened, stiffened main frame, plus new aluminium subframe that also forms the seat base.  

The result of this extreme dieting? The R100X now weighs just 165kg ready to rock, 40kg less than when it left the factory. 

Got deep pockets? 

To make room for his next project, Norton has listed the one-off R100X for sale. Want it? That’ll be £40,000 please. With so many hours invested it was never going to be cheap. The engineer is also selling off his supercharged R100RT ‘Kompressor’ too. 

Norton's BMW R100X uses an lengthened R100RT monolever swingarm - photo credit Christopher Bailey

Stop the show 

Upfront, a Brembo caliper grabs a beefed up 320mm disc. The rear brake is still a drum, but has been converted to hydraulic action for added stopping power. Brake lines throughout are all custom affairs made by ATEC. 

Let there be light 

Adding to the iconic desert racer looks are a pair of bugeye Baja Designs headlights upfront – good for nearly 10,000 lumens. 

Ultra-bright Baja Designs headlights sit upfront - photo credit Christopher Bailey

Trick loom 

Norton says that the whole wiring loom can be removed in a jiffy by simply removing three bolts, thus making it possible to jet wash the bike without incurring any unwanted water ingress.