This is the XStreme 650, a meticulously crafted 1975 Yamaha XS650.
The XStreme 650, built by Derrick, known in the custom motorcycle community as Captain Awesome of Mulligan Machine, is more than just a bike; it’s a legacy.
“Growing up, Dad gave me a lot of things preparing me for life. One that sticks out high in my mind was… knowledge of all things mechanical,” Derrick reminisces.
This profound statement sets the stage for a build that is both a tribute to his father and a gift to his son.
A Build with Heart and Soul
The journey of the XStreme 650 began in 2007, as part of the TCU 2007 build-off competition.
Although the bike wasn’t completed in time for the contest’s conclusion, the process itself was an invaluable experience for Derrick. “The bike was rode in the raw steel for almost 2 yrs before I decided to powdercoat and paint the bike,” he recalls.
This period of raw, unadulterated riding speaks volumes about the bike’s rugged, unyielding character.
Craftsmanship and Ingenuity
The foundation of the XStreme 650 is a 1975 XS650 that Derrick acquired from Glenn, known as Animal on the chopperunderground.com board, in exchange for some repair work on a Triumph rigid frame.
From there, Derrick’s vision began to take shape, starting with a custom 1” stretch rigid tail section. “In the process, I extended the backbone approx 5” to get rid of some of the forwardish look to the bike,” Derrick explains.
This modification not only altered the bike’s stance but also provided a solid platform for the solo seat setup, complete with a urethane-filled, machined telescoping shock and a seat rail to ensure safety.
The I-Beam Springer: A Labor of Love
One of the most striking features of the XStreme 650 is the I-beam springer front end, a component that Derrick had envisioned for quite some time. “Using some rail channel welded back to back to give it an industrial look,” he describes, “this was bent using a HF bender (with some modifications) and the rear main leg were split and tapered.”
The result is a front end that combines both aesthetic appeal and functional integrity, embodying the industrial strength that Derrick aimed to achieve.
Performance and Personal Touches
Performance enhancements were not overlooked in this build. The exhaust system, crafted from 1 ½” 2 ½ radius combo bends from The Chassis Shop, is a testament to Derrick’s attention to detail.
Additionally, the crank breather routed to the header—a technique borrowed from circle track racing—helps to evacuate crank pressure, a nod to the builder’s racing background.
Derrick also took the time to fabricate a custom single intake for the XS650, a task he had undertaken for several bikes in the past. “Each one is a little different, but this one looked good and works well,” he notes. The rejetting process, involving precise drilling, ensured optimal performance.
Aesthetically, the bike features unique touches like the finned covers. “I first welded up the filter cover, and bypassed the oil return from the original filter cavity and added a port from the oil pump,” Derrick explains. The aluminum strips, TIG-welded and ground to give a cast look, add a distinctive flair to the bike’s appearance.
A Legacy for the Next Generation
The culmination of Derrick’s hard work and dedication is a bike that not only performs exceptionally but also holds deep sentimental value. “My son loves the bike, and his skateboarding buddies,” Derrick proudly shares. The XStreme 650 is more than just a motorcycle; it’s a tangible connection between father and son, a piece of Derrick’s legacy that his son will cherish for years to come.
