Custom Honda GB400TT Is a Stunning Cosmetic Nod to the Old Days of Tourist Trophy Racing

First released in Japan during the mid-eighties, the model took stylistic cues from the high-performance British motorcycles of yore. It was named after the legendary Tourist Trophy race held on the Isle of Man, and would eventually evolve into the larger GB500 available in Western markets. Given the GB’s rising popularity as a collectible, few people would ever venture to have one such specimen modified irreversibly.

Nonetheless, an amateur builder from Sydney, Australia named Sam Troy did just that, and the result is rather spectacular to say the least. Having grown up around motorcycles thanks to his father, the Aussie knew he wanted a fully-fledged custom ride before he even got his license. The original plan was to base it on a Honda CB400/4, but Sam quickly discovered that his budget wouldn’t quite allow it.

Despite feeling rather discouraged at first, he kept looking and eventually came across a GB400 TT which had seen better days. Sam concluded that it would be a good fit for the project he had in mind, so the purchase was swiftly made despite the bike’s shoddy condition. At the end of the day, it came at a pretty fair price and didn’t have to be pristine since it was due for customization, anyway.

The GB400 slowly morphed into its current form over a three-year period, yet this process was far from smooth sailing. Sam had to move houses on no fewer than three occasions during that timeframe, all while attending his day job and only getting the time to work on his machine in the evenings. Still, it all came together with the help of some friends and a couple of pros.

First things first, the project’s author had the electronics completely refurbished, because they were an absolute mess when the GB came into his possession. With these sorted out, he picked up the phone and called Trev of Surfside Motorcycle Garage, tasking him with an extensive overhaul of the bike’s single-cylinder engine. Following this rebuild, the mill was also treated to some fresh exhaust plumbing.

The pipework makes use of stainless-steel XBR500 headers from Black Widow, joined up to reverse megaphone mufflers developed by Cone Engineering. Besides refurbishing the powerplant, Trev also fabricated some custom brackets to get the new exhaust secured in place. He worked some magic in the footwear department, too, fitting the GB400TT’s wheels with youthful stainless-steel spokes.

Now, the real showstopper on this build is clearly the bodywork, more specifically a gorgeous aftermarket fairing with classic Isle of Man TT vibes. It’s been sourced from Airtech Streamlining and painstakingly adapted to fit the GB without creating any clearance issues. Sam built all the corresponding brackets from scratch, lending a helping hand from two of his friends as he went along.

Atop the vintage-looking fairing lies a clear Gustafsson windshield, while a compact front fender from Mostyn can be spotted lower down. In the cockpit area, Sam Troy’s ravishing GB400 is outfitted with Tommaselli clip-on handlebars, featuring aftermarket bar-end mirrors and a Suzuki’s front brake master cylinder. On the other hand, the motorcycle’s twin factory gauges have been retained, as were items like the fuel tank, side covers, and stock suspension.

You’ll see a pinch of fresh componentry at the back, though, in the form of a GB500’s seat and cafe racer tail unit. The latter is flanked by LED turn signals from Posh, and the rear-end lighting suite is finished off with a Bates-style taillight. Right beneath it, Sam installed a compact license plate holder to keep things nice and clean but also street-legal. Moreover, he finished off the creature’s ergonomic package with a pair of CNC-machined Raask rearsets.

With the whole project finally coming together the way he wanted, it was time to handle the paint job. This work was once again outsourced to a professional for the best possible result, and the chosen livery is one of our favorite things about this entire build. Executed by Sam of Colourfuel, it employs a delicious shade of teal as the base hue, along with white highlights all throughout the bodywork.

A long clean stripe runs from front to back up top, and the white patches on the side fairings are filled with black graphics. They depict the manufacturer’s name and the number 22, but we’re not sure what sort of significance the latter might hold for the owner. To give you our best guess, it might be a sneaky reference to the age Sam Troy finally got his motorcycle license, because he did say he was a bit of a latecomer.