Why Do Harleys Break Down So Much?

Have you ever wondered why some Harley-Davidson motorcycles have gained a reputation for frequent breakdowns? This perception isn't entirely unfounded, especially when considering the manufacturing history of these iconic bikes. Here's an in-depth look at the evolution of Harley-Davidson's quality and durability, focusing on the challenges and improvements over the years.

The Past: Manufacturing and Maintenance Challenges

One of the oldest metric bikes I've encountered on the road was a 1977-80 shovel-nose model, which I sold in 2015 due to personal issues. Although it wasn't the prettiest, it gave me much enjoyment during its service. This bike, like many of its contemporaries from the American Motorcycle Association (AMF) era, had a rigid frame and only a kick start. Interestingly, a 1973 Harley-Davidson was also present in the same vicinity during those years. Both these bikes showcased the manufacturing quality issues that plagued Harley-Davidson during that time, especially compared to current standards. However, these bikes are noteworthy for running well despite their age, thanks to the durability of the materials used.

While it's true that these classic bikes will endure for decades due to the non-degradable nature of plastic parts, their operational quality is questionable. The reliance on plastic parts aside, these early Harley-Davidsons, particularly the early FLH models used by municipal police departments, struggled with significant vibration issues. A comprehensive review of maintenance records from the early 1970s revealed that not a single one of the police bikes acquired that year showed any signs of vibration problems; they all required engine removals and machine shop diagnostics for assembly issues.

The root cause of these issues was traced back to grossly unacceptable runout in the flywheels, which were improperly assembled and shipped. The assembly process itself had been disrupted due to labor disputes, resulting in untrained supervisors and strikebreakers assembling Harley-Davidson engines. This poor quality control led to the bikes vibrating so wildly that they would blow out headlight bulbs in a single day. The solution? A complete dismantling, disassembly, and reassembly of the flywheels to meet factory standards. This painstaking process was the impetus for the reputation of new Harleys as being less reliable.

The Present: Reliability and Modern Manufacturing

Thankfully, the situation improved significantly with the introduction of the Evolution (EVO) engine era. Harley-Davidson addressed the quality control issues by ensuring that their manufacturing processes were more stringent and that only skilled workers were involved in the assembly and inspection process. Modern Harleys today proudly stand as a testament to the brand's commitment to producing reliable and durable machines.

For a time, due to these past challenges, riders had no choice but to perform their own maintenance and repairs to save costs. This led to a significant number of Harley-Davidsons breaking down on the roadside, which further fostered the brand's reputation for unreliability. However, with the advancements in manufacturing and better-trained mechanics, these issues have largely been resolved. Modern Harleys are now as well-made and dependable as any other premium bike on the market.

In summary, while the reputation of frequent breakdowns on early Harley-Davidsons was well-deserved due to manufacturing quality issues, the brand has come a long way. Today's Harley-Davidsons are significantly more reliable and hold their own against any other brand in the market.