Preliminary Evaluation PE21-003: Extended Stopping Distance

The Office of Defects Investigation (ODI) opened this Preliminary Evaluation (PE) based on twenty-two (22) Vehicle Owner Questionnaires (VOQs) for soft rear brakes caused by air seeping into the rear brake lines of model year (MY) 2012-2020 Ducati Monster, Multistrada, SuperSport, Panigale, Scrambler and Diavel motorcycles.

The consumers were alleging that the rear brakes would not properly function unless the rear brake pedal was applied several times or that there was a total loss of rear braking during normal applications, increasing the risk of a crash. In a March 2020 meeting, Ducati indicated that they were aware of certain models in which air may enter the motorcycles' rear braking system through the brake lines, due to exposure to heat from the exhaust system. Although this condition compromises rear braking performance, Ducati stated that they did not consider this to be a safety defect because the front and rear brake systems are hydraulically independent from each other, and a motorcycle's front brake system performs most of the stopping. Additionally, they believed that routine brake fluid replacement would resolve consumers' concerns, however complainants and dealership service technicians reported that, in some cases, after a dealer serviced the rear brake system, the rear brake pedal would feel soft and spongy again (indicating compromised brake performance) less than a year later--well before the recommended two-year brake fluid service interval. As a precaution, Ducati issued a series of technical service bulletins (TSBs) to replace the brake lines with redesigned ones, rerouting them away from the exhaust system.

ODI's position is that all of the brakes on a motorcycle are considered necessary for safety. Analysis of the data identified that neither the entire model line nor the entire model year range of motorcycles covered by the investigation were affected, but rather certain sub-models or narrower model year ranges of motorcycles incorporated brake lines with a higher exposure to the heat from the exhaust system. Because of the unique routing of each model's brake line, some motorcycles are more susceptible to the condition than others. As these specific models and model years were most likely to exhibit an increased risk of a crash from the lengthened stopping distance, Ducati converted the previously issued TSBs into a safety recall.

After receiving a total of 94 VOQs, ODI is closing this PE with Ducati's safety recall 21V-315. With the recall action taken by Ducati, this investigation is closed. However, the closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist on other models or MY vehicles outside of the recall scope. The agency reserves the right to take further action if warranted by the circumstances.