Tim Roberts of Roberts Performance Group has a long history in building race cars, where weight, clutter, and weakness is the enemy. He has brought that same mentality to his bike builds, and it shows. Last year, his first build, a Yamaha Virago, was third on our list of the Best Custom Bikes of the year.
Now Tim is back with his second build, a ’74 Honda CB360 scrambler, which he’s dubbed “Blue.” This was a budget-conscious build with a rough-and-ready attitude, and we’d love to put this little brawler to work on some of the trails in Tim’s home state of Colorado.
Below, Tim gives us the full story on the build.
Honda CB360 Scrambler: In the Builder’s Words
(Words by Tim Roberts of RPG. Highlights by us.)
A little bit about me:
I’m a designer, moonlight fabricator, and bike builder based in the Denver, CO area. This is my second bike build, commissioned by a fan of my previous piece. My design inspiration comes from my love of building and racing cars. When building racecars every component is on the car because it HAS to be there. Every part serves a purpose and is optimized for that purpose, otherwise it’s just extra weight and clutter. I use the same philosophy with my bike builds. I think this gives my work a very clean and purposeful look where there’s no place for poor craftsmanship to hide.
A little bit about the bike, “Blue”:
The owner of this 1974 Honda CB360 is a recent transplant to Denver. He had reached out to several other builders in the area but got no response. I answered his call and we began to plan out the build immediately. The donor was a clean but well used commuter bike that lived its life on numerous college campuses and military bases along the East Coast and Midwest. He wanted it turned into a light and nimble scrambler that could tear up the city streets as well as the mountain dirt roads. He wanted big fat knobby tires, an open ‘triangle’ under the seat, wrapped headers, and an overall rugged look. Everything else was up to me.
Since this was a budget-conscious build we opted to keep the tank original and engine internals stock. The engine was cleaned up, painted, and given some fresh hardware. A custom under-frame exhaust was fabricated using a small bullet muffler that tucks neatly between the frame rails. The tank got scrubbed down then buried under several layers of clear coat to preserve the 42 years of patina it had earned. I also slightly repositioned the tank on the frame to line up better with the new low profile seat.
Frame work began by completely chopping off the rear half and fabricating a new sleek structure to integrate the seat, high mount fender, and passenger pegs. The remaining half of the factory frame was de-tabbed, stripped, and smoothed before getting a fresh coat of gloss black urethane. Motocross pegs were also adapted to the reworked factory mounts.
A beefier CB550 front end replaced the original components. I drilled and scalloped the CB550 front rotor and adapted it to a CB360 hub and 18″ rim. The front fender was dug out of a pile at the local wrecking yard. It sits perfectly tucked up to the lower triple with a simple bracket that doubles as the headlight mount. Longer rear shocks were fitted to the new subframe and stock swingarm to give the bike a bit more travel and ride height. Identical Bridgestone TW42’s are fitted the front and rear rims. The rear drum brake is stock but the tension rod, linkage, and pedal were reengineered.
A custom wire harness was built with modern automotive connectors and new electronics to replace the factory ignition and charging systems. The LED headlight and strip tail lights help keep current draw low so I could use a battery small enough to tuck between the frame rails above the air filters. The gauge is a KOSO T&T digital/analog unit that neatly keeps track of all the bike’s vitals. Rider controls are a mix of finds from various late model sport bikes and wrecking yards.
I think the bike came together perfectly. I really love how rugged and raw the bike seems yet there are so many little finely finished details to take in when you look closer. Best of all, the owner is overjoyed with his new old bike