There?s something about a classic Triumph dirt bike: the appealing proportions, the chunky rubber, the swept-back bars and the plush seat. Put them all together, and you can almost hear a ?click.?
Vintage off-roading Triumphs are variations on a formula?but like songs of AC/DC, the formula works. And one of its greatest proponents is Hayden Roberts, an expat Brit living in California who runs the Hello Engine workshop.

Hayden?s latest build is this stunning Bonneville TT special. It was commissioned by Randy Torres, a sound effects editor who has just finished the movie Tenet.
Randy lives in Pioneertown, California, which is a living, breathing film set near San Bernardino worthy of a story in its own right. For off-road riders, Randy says it?s like ?living at the beach if you’re a surfer.? (These photos were taken there, with a 30,000-acre wildfire raging in the distance.)
Randy has a collection of stock bikes, including a classic Yamaha TT500 and a Ducati Multistrada, but he?s also partial to the odd custom.
?I?ve been a big fan of Hayden?s builds for a long time,? he tells us, ?so I hit him up to build a desert sled a couple of years back. Then I realized that I had enough dirt bikes in the garage?and wouldn?t want to dump a nice vintage Triumph on top of some boulders. I asked if we could do a ?TT special? instead.?

After kicking around a couple of ideas, and poring over archive images from the Ascot Park speedway track, Hayden had enough to work on. And ...