Once again Purpose Built Moto steps on new ground for the shop with this Custom Harley-Davidson Fatbob. Built around the M8 Engine and frame, this bike rolled into us reasonably stock, with only a few thousand KM’s on it. Phil had been coming into the shop trying to find his perfect bike for a while, test riding and buying a few bikes before he landed on his new Harley. The torque, and thunder from the M8 powerplant instantly grabbed his attention and after a few rides he was hooked.

That’s where the conversation started with building him a custom Harley Davidson that would suit his new found riding love. Our rider found himself on destination-less rides through northern NSW and regional QLD often staying out overnight after winding his way down gravel roads for the day. Phils needs involved creating a better handling motorcycle, retaining an upright “all day” riding position, removable luggage racks for his weekends away and releasing a bit more power out of the bike. His wants were more aspirational, chasing some unique tracker styling, custom wheels to suit sportier tyres , and a snarling performance exhaust. 

With this brief we got to work, first focussing on setting our foundation with the suspension and wheels. As the Australian distributor for Canyon wheels, we reached out to the guys for a set of lighter custom wheels. Canyon wheels offer a huge range of finishes, so we landed on using their gloss black spokes and hubs, with a candy copper fat spoke set up. Running 5.5” x 17 front and rear, using a set of dual sport Pirelli MT60RS tyres. These have a light off road tread, without sacrificing street rideability or handling, the perfect choice for Phil as he heads off into the country for some gravel road domination.

Paired with this was a complete braking upgrade from Lyndall brakes and Brembo. Using a set of radial callipers and a rear calliper kit from free spirits parts. We’ve also fitted a set of performance machine mid sets pegs that set up for that perfect riding position. 

My next job was to figure out how to create a tracker style tail and mount on this less than inviting frame. The solution was a hand shaped aluminium box that lifted the rear profile closer to a flat line with the tank. This provided a base for me to build the tail section, and provided some good storage under the seat for the rider to stash tools, camping gear or whatever else he needs on those weekends away. This hand build section mounts to the frame rails and curves up to create a thinner seat section.

Next task was to get this tail section shaped. This one was a great exercise that taught me a lot about sheet metal shaping, creating a nice rounded tail that suited the new lines we were creating and the factory HD tank which was to stay in place. I’ve used these fatbob tanks before on some other bikes and really love the shape, so it was a no brainer to keep it as is.

We’ve retained the factory headlight, another nice piece from the standard bike, custom fabricated a set of fork shrouds, and set up a swing arm mounted number plate holder. This houses the plate lighting, and a set of our 3 in 1 omni lights. A new product we’ve been road testing that is about to launch.

The rear lighting is set up to use our omni lights as a brake and indicator light, with a set of LED lights frenched into the tail that act as the tail/brake lights aswell.

Between Dylan and Myself the end result of the new body work fabrication is a wildly different custom Harley-Davidson that you can’t really put into a category, its just a well executed custom with blends of Cruiser, Dirt Track and ADV styling. We’ve just been calling it the Gravel Gorilla. 

With the Styling of the bike taking shape it was time to build the exhaust to suit the new body work. We’ve dreamed up a 2 into 1 into 2 set up that utilises a pair of Competition Werkes Mufflers. Delivered in a ceramic coated black, Dylan has custom fabricated a seamless, single piece header set up with a 2-1 collector that keeps the shape of 2 separate pipes. Exiting on and angle behind the riders foot peg. With the welds finished the system was sent for black ceramic coat and Jesse got to work on the engine. 

The motor has been kitted with a Stage 3 Scremin Eagle kit, and a whole suite of Arlen Ness x Rough Crafts engine covers. Finished in a crispy anodised black this kit gives an ultra nice finish that would later tie the design of our paint through. Our final job on fabrication before final finishes started was Phils weekender bag racks.



Shaped out of chromoly tube, and mounted to some spare threaded frame mounts we’ve made a set of saddle bag brackets, that are removed with 3 bolts each, and a tool bag rack that’s fitted to the custom risers we designed and had machined to lift the bars and offset them rearward for a better ride position. Throw a set of soft bags on these racks and you’re ready for a weekend away in about 15 minutes.

We had 2 stops left before test riding, first was paint. We’ve linked up again with Nathan from Livin Loco Garage to create a surreal and very unique paint design. I took Nathan a few loose ideas, and some colours we wanted included and over a couple hours he’s sketched out and started work on the impressive, yet understated paint work. Blending A predominantly black design, with some copper candy, copper leaf detailing and flat grey hand brushed pin stripes. The best results in paint work always come when we give our painters a few specific points to be included and let these artists do what they do best, paint. 

Second stop was a trip to Jamie at Dynomite moto to have this sledgehammer dialled in with its new intake and exhaust with a custom tune. Jamie has done his thing and delivered an M8 that runs 116HP at the rear wheel, and 125Nm of torque at around 4500RPM.

The test rides proved this bike was going to impress our rider, with considerably sharper handling, and a great cornering feel, partnered with that extra power that’s been unleashed this thing is a handful in the best way possible. Harleys are a love or hate sort of thing for most riders, but most on the negative side have never ridden one for what it was supposed to be, a long range power cruiser. Our custom Harley FatBob will undoubtedly deliver years of weekend enjoyment for Phil, and with its improved suspension and mild off road capability, any roads would be a welcome sight on the affectionately named Gravel Gorilla.

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Purpose Built Moto is home for unique custom motorcycle builds. We offer a unique motorcycle customizing experience in the heart of the Gold Coast.

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