Harley-Davidson® Factory Racing competes in the King of the Baggers series, a one-of-a-kind motorcycle competition bringing together the best riders in the world to race souped-up Harley-Davidson Road Glide® motorcycles.

To better compete in the race, the Harley-Davidson Factory Racing team needed to identify ways to reduce weight, increase speed, and decrease the lean angle of the large bike during turns. These adjustments would be complex due to the bike’s touring body design—especially when compared to Superbikes built for racing at breakneck speeds. To start off, the production Harley-Davidson Road Glide motorcycle weighs up to 960 lbs. 

Harley-Davidson Factory Racing engineers constantly iterate designs. Their year-round need for quick-turn parts across a variety of manufacturing processes brought them to Protolabs and their digital manufacturing expertise in search of a partner that can provide both prototype and race-ready parts. The partnership has allowed the engineering team to apply key learnings from a Sunday race and translate that knowledge into a new part design. The team can prototype, test, iterate, and order the final part using a race-ready lightweight material—all before the green flag drops the following weekend.

According to Harley-Davidson Factory Racing Team Principal, Jason Kehl, “For us to be successful, we need to respond rapidly to what we are learning on the racetrack. To do that, we require a partner that is able to bring these ideas to life. As a digital manufacturer, Protolabs allows us to make those weekly incremental improvements that lead to season-long success.”

Tight turns on the track are pivotal to the team's success. Just one-half degree of extra lean angle during turns can reduce track time by about 1/10 of a second. With some racetracks sporting as many as 14 turns in a single lap, the benefits of increased lean angle are clear.

Harley-Davidson Factory Racing engineers constantly evaluate how they can modify parts on the bike to add extra lean angle, which can help maintain performance and comfort for the rider. The exhaust components on the right side of the motorcycle offered the best potential for improving lean angle, so the team turned to the design freedom of metal 3D printing at Protolabs.

The result was an organically designed exhaust that tucks in closer to the bike, ultimately allowing Wyman and Rispoli to ride closer to the ground on right-hand turns. The DMLS-printed (Direct Metal Laser Sintering) exhaust utilized titanium for a lightweight, organic design.

King of the Baggers riders race rain or shine. As you might expect, bad weather creates several on-track challenges. With riders handling the 620 lb. bike at high speeds in tight turns, hydroplaning and crashes are common. Finishing the race in even the worst conditions is paramount for the season-long points race, as failing to cross the finish line—even in last place—results in a steep slide down the leaderboard.

When a bike does go down, protecting critical parts from damage allows riders to continue competing. The shift assembly tops that list as it is especially susceptible to damage due to its position on the bike’s left side. The part, built to protect the shift assembly, is intended to take the brunt of any damage.  Harley-Davidson Factory Racing engineers designed the shift skid that Protolabs machined and delivered in two days. Requiring mandatory tight tolerances, the part was manufactured using 3+2 CNC machining. In the end, this part allows riders to continue competing for precious points throughout the season.

Collecting first-hand feedback from the racers as they return from the track and combining that with quantitative data analyzing performance in every straightaway and turn fuels the bike’s evolution. Protolabs is able to manufacture quick-turn, high quality parts, speeding iteration of injection-molded, CNC-machined, 3D-printed, and sheet metal fabricated parts.

For more information: 

Protolabs

American Motorcycle Association