At the close of the previous year, our exploration into the realm of European custom Harley-Davidson motorcycles introduced us to something known as the SPS 4. Originating as a Sportster of the S 1250 variety, it underwent modifications in Germany by Thunderbike, resulting in a ride that commands attention and leaves a lasting impression.
The SPS is not an isolated custom motorcycle at Thunderbike but rather a family of bikes crafted over time to amplify the aggressiveness of stock Sportsters. Recently, this family welcomed a new member known as the SPS 5.
Described as the stage-one version of the SPS 4, the SPS 5, like its predecessor, is based on a Sportster S but has been transformed into what Thunderbike describes as the “perfect acceleration orgy.”
This doesn’t imply a replacement of the original engine with something more potent to achieve higher speeds. Instead, the original engine remains, albeit with enhancements like a custom two-in-one Dr. Jekill & Mr. Hyde exhaust system. The focus here is on enhancing the sensation of acceleration.
Adding to this sensation is the rear-mounted footrest system complementing the mid-controls, along with new wheels to intensify the feeling of speed. These wheels are simple yet effective bobber wheels wrapped in the base motorcycle’s original tires, with the front one retaining the original single-disc brake.
To enhance the riding experience, Thunderbike also revamped the seat of the Sportster, swapping out the stock seat for one with more pronounced edges to prevent sliding. Paired with narrower handlebars, the rider experiences heightened control and comfort.
In total, Thunderbike lists 25 major aftermarket parts used in the build, valued at a combined 7,000 euros. This figure excludes additional components like the exhaust system, labor hours, and the striking paint job—a blend of Bright Brilliant Blue with bronze accents.
While the current rider of the Harley-Davidson SPS 5 remains undisclosed, its distinctive presence ensures it won’t go unnoticed in your neighborhood.
