Custom Triumph Bonneville Merges Countless Repurposed Parts Into a Tasty Dirt Tracker

He still finds the time to indulge in the occasional custom project, though, and the results are always worth looking at many times over. Take, for instance, the mouth-watering Triumph Bonneville dirt tracker he’d worked on a few years back. We’re calling it a Bonnie due to the engine along, though, as the bike is actually more of a parts bin special rather than something based on one single donor.

Having collected a ton of spare parts in his workshop over the years, Hayden didn’t have much of an issue sourcing the necessary parts for this project. That’s not to say the process of piecing everything together was easy, mind you, but a builder of Sir Roberts’ caliber certainly doesn’t mind a good challenge. Finding an appropriate skeleton was the first piece of the puzzle.

Luckily, he had a competition-spec Triumph frame from 1965 lying around the shop, and it was deemed perfect for his needs. Things got a bit trickier when it came to the powertrain, because Hayden had to do some web browsing in search of a suitable mill. He eventually found a 750cc Bonneville motor from the late seventies while looking through Craigslist and it wasn’t long before he got on the phone with the seller.

As soon as the parallel-twin mill arrived at his garage, the custom sorcery got underway in earnest. Triumph’s powerplants came with a left-side shifter from 1975 onward, but our protagonist wanted to switch back to something more traditional. He therefore relocated the shifting mechanism to the right-hand side, enhancing the motorcycle’s vintage appeal right from the get-go.

The engine-related work continued with the installation of high-compression pistons, a CDI ignition system, and fresh Mk II Concentric carbs from Amal. Replacement cams also make an appearance, while the crankshaft was lightened and rebalanced during the overhaul. On the exhaust side of things, we come across shiny stainless-steel plumbing with nothing to muffle the engine’s roar. A layer of chrome plating covers the headers from front to back.

Items sourced from various other Triumphs include the rear drum brake, folding foot pegs, and under-seat oil tank. The fuel chamber was donated by an unidentified 1966 model, but the rectangular side cover on the left is a custom unit fabricated from scratch. Hayden shaped the front number board in-house, as well, while ordering a fresh seat pan from Iron Cobras and topping it off with generous padding.

He went with white glitter vinyl for the saddle upholstery, giving the motorcycle some extra visual bling where you’d least expect to see it. The whole shebang rolls on shouldered Akront rims, linked to Buchanan’s stainless-steel spokes and shod in Duro tires at both ends. Hayden fitted a handmade aluminum fender nice and high above the rear wheel, right beneath the subframe tubing and license plate holder.

A repurposed drum brake provides stopping power up north, equipped with new shoes just like its rear counterpart. In terms of suspension hardware, you’ll find Ceriani forks at the front and a pair of NJB shock absorbers at six o’clock. Hello Engine fitted a small circular taillight near the upper shock mount on the left, but that’s the only lighting component you’ll see on this machine.

Turning to aftermarket solutions for the cockpit area, Hayden installed a wide handlebar complete with rubber grips and a Tommaselli throttle. There are no dials or rear-view mirrors to speak of, and even the headlamp was left out of the equation for a quintessential tracker look. Last but not least, the vibrant color scheme is what drew our attention to this custom Triumph in the first place.

Both hues employed here were taken from Rolls-Royce's vintage color palette – Peacock Blue for the frame and Regency Bronze for the gas tank. Most of the other bits and pieces were left unpainted to give this handsome tracker a raw vibe, but the Hello Engine treatment saw them polished to look as good as new. Together with the glitter vinyl seat, the whole affair is absolutely delicious to say the least!

Aside from all the cosmetic eye candy, Hayden also managed to extract around 20 percent more power from the Bonneville engine. The fruit of his labor is nothing short of fascinating, thanks in no small part to its classic desert sled charm and all the work put into it. Hayden Roberts may not indulge in fully-fledged custom builds on a regular basis, but he knocks them straight out of the park when he does.