The Triumph Bonneville Desert Sled is one of my all time favourite motorcycles. They have a rich history in motorsport and they are so much fun to ride. I was stoked when a client came to us saying that his dream motorcycle was a 60’s inspired Triumph Bonneville Dessert Sled with all the functionality of a modern off road bike. This was going to be fun. 

So many good things came out of the 50’s and 60’s. They inspired so many cultural movements, but my personal favourite is the revolution of Desert Racing. The wildly American version of the Scrambles held in the UK. Street bikes stripped down, with knobby tyres, lifted suspension and as much weight as possible removed pointed at a searing hot desert and held wide open for as long as you could hang on. 

The Bikes were slapped together with crudely modified parts and anything the riders and mechanics could get their hands on in the name of speed. I love the idea that drives this form of racing, especially the privateers out there giving it a go. If you haven’t seen it, check out Bruce Brown’s Hare and Hound on Youtube. Keeley Pritchett’s Wide of the Mark triumph was crafted in this style of desert racer, which I drew some inspiration on for our 1973 Triumph T120 Desert sled resto-mod

That job led us to this build. Charles, our rider, reached out just as we finished the 1973 Bonneville with an idea for his dream bike.

He wanted a late model triumph for the reliability and ease of use, but with all the style queues of the 60’s desert racer. The only response needed was “sounds good, let’s do it”. So I went shopping for a donor bike and got started. We landed on the first of the EFI Bonneville 900’s. I was chasing a 270 deg scrambler motor but at the time they were hard to find for a good price. That said the low mileage Bonneville was perfect for what we needed.

First step, tear down. We will measure up the wheels, ride height and suspension here once all the unused parts have been stripped off. We went with some high polished 18” H pattern rims laced to the standard Bonneville hubs. The suspension was lifted in the back with some new YSS shocks and stiffened up slightly in the front as we stripped and polished the fork legs and rebuilt them with new internals. 

With the wheels built, we grabbed some Pirelli MT43 in a 3.50 – 18 fitted them up and there it was our ride stance. Looking at the rolling chassis, engine and tank on the bench we started fabrication with some specific rider requests. Charles wanted a set of Webco style bars, essentially a set of high bend tracker bars with a rounded crossbar for bracing. Very fitting for the style so I was happy to oblige. Fenders and subframe came next starting on the front. A very simple fab job made easier with our DIY fender kit, shaped and welded in a fork brace style fender mount with all parts polished.

The rear subframe and fender were a little more involved. Not because it was hard to build, but it was hard to wrap my head around creating something so ill fitting. The idea here was to intentionally make the seat and fender not fit perfectly. Remember what I said about these bikes being slapped together? I had to channel that and build the worst fitting fender and seat set up I’ve ever done, and its glorious.

Starting with chopping the rear frame rails and fabricating a hoop that would act as a grab rail and fender mount. The fender sits underneath mounted to a couple of tabs and linking up with the stock cross brace under the seat. I’ve also included a plate mount welded to the fender, and integrated a tail light mount into the hoop that routes hidden wiring back to the electrics tray. Our polished Dome indicators were placed just rear of the shocks to keep the tail and seat section as clean as we could. 

The seat pan was given the same horrible fit, with air gaps and cut outs galore. Built in a Bates style and mounting to the fender directly by way of a hand made seat bolt. This is to allow the removal of the seat without any tools. A tiny little crank handle that latches into a hidden channel behind the seat leather. A trick little detail to elevate the finish of this very haphazard tail section. I will say though, I do love it. To my eye it’s perfect according to the style of the time. 

Next I set about getting the front end dialled in, this included the new bar risers, 3 button switches, the vintage style incandescent headlight, custom fork mounts and a speedo cup. Most of our builds wear the PBM LED headlight range, but if they’re not right for the build I’m not going to force it. This build called for something more vintage and shiny. A slim headlight bucket was fitted to a custom set of fork covers and mounted super close into the forks. Polished Dome indicators have been used as the fixing bolts for the set up.  The gap on top would be filled with a stainless steel Speedo cup that houses the Daytona Velona W gauge, check these out on our website for more info. We love ‘em!

The levers used were a set of Kustom Tech chrome levers. With that the gleaming front end was complete, once finished itb would be dripping in chrome and polished parts. Definitely one of my favourite parts on this build

Last on the fabrication was the exhaust and custom side covers. We had removed the airbox, but retained the battery box, internal rear fender and fuse box mount. That meant side covers were necessary to finish out the smooth styling of this body work. The exhaust was to be fabricated first though. Desert sled means high pipes, and having previously used a single side set up on the T120 restoration I wanted something new for this bike. 

Twin high pipes was the answer, with an oversize header and hidden muffler section these pipes give that distinct 60’s straight pipe look, but subdue the bark of the triumph twin enough to keep your neighbours happy. Fabricated, purge welded and polished up these pipes have goldened up beautifully on our test rides. The shape of the body and engine on these bikes allows the exhaust to tuck in nice and close which helps us avoid the need for heat shields on the section that may come into contact with the rider. 

The bike was looking amazing on the bench at this point and we were excited to put the final fabricated pieces in place. The side covers needed to work in with the very rounded shapes on the fender and tank so we got to bashing some aluminium until it looked right. A perfect transition between frame and exhaust.

The custom Triumph Bonneville was in bare metal as I sat down with some tape and markers to design the paint before it went off to Justin at PopBang Paint. We had a nice flat blue mixed up and laid down next to a beautiful off white. I had a creeping feeling it was time for me to do a white seat and this was the perfect bike for it. Trimmed up by Vintage Seat Co on the gold coast. This seat and grips combo will only get better with age as they get dirty and work in to show their age a little better. 

This photo set came together out of pure luck, I had taken the bike out to some back roads on the Gold Coast for the Go-pro test ride we put in all of our YouTube videos. As I was unloading the bike Brandon our photographer just started shooting and after a minute or so told me we had to stay and shoot the desert sled in this clearing of the forest. Very fitting for our modern day gravel muncher. 

As you’ll see in the build video the test ride that came after was a lot of fun. Some tight corners winding through some incredible forest on the doorstep of the Gold Coast. The rumble of this twin echoing through the trees and back into my helmet put a smile ear to ear. We’ve dragged this triumph back a few decades but kept the styling truly timeless. This thing will look as good as it does today no matter what year you place it in.

This triumph is now bound for Canberra, where the rider is ecstatic to jump on for his first ride. Thanks for the trust Charles – Enjoy!

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