Your Bike and the Good Vibes

Vibration can be objectively measured and analyzed with computer programs and technical equipment like oscilloscopes and such, but how does this subjectively affect us as motorcycle riders? We want a smooth ride, yet we're willing to pay money for a vibrating lounge chair or pay for a vibrating foot massage after a day walking around on a Motor Show, and clearly loving it. Proving, I suppose, that all vibration isn't bad. Thus it is with Harley-Davidson's that are powered by the inherently imbalance 45-degree V-twin engine.

Vibration comes in many forms. When I started road-testing motorcycles back in the early 80s, I rode all manner of motorcycles: European, Japanese, American and a few from behind the iron curtain – everything from 50cc singles to huge six-cylinders. Believe me, I've been vibrated every which way but loose, from a in-line four that had a high-frequency/low amplitude vibration - a tingly, buzzy, irritating feeling – turned my hands numb. Then there were Harleys with solid-mount engines like the before 2004 Sportsters and four-speed Fls that shook like a possessed demon doing a medieval exorcistic dance. But the character of those two types of engine vibrations is dramatically different.

When a Harley-Davidson sits at idle it can rattle the whole bike, which is not exactly a vibration, it is more like a shaking. Rubber-mounted engine isolation like that on most modern Harleys allow the engine to jump around of its own accord, which shakes everything form the mirrors to the rider's eyeballs. I call this shaking as opposed to vibrating. Shaking moves things in a big way, while vibration buzzes and tingles and whether or not it irritates or pleases me.

Depending on what you happen to like, vibrations could be interpreted in several ways: 'My God, it's falling apart and I am going to die,' or 'Wow, this feels cool and I want some more.' The important thing is that although I could feel vibration it doesn't really bother me.

Vibration is not necessarily something bad; it can actually be a pleasant sensation. Yes, some motorcycles have moments of shaking and vibrations, but I for one am grateful that the feeling reminds me it is a motorcycle powered by a mighty-combustion engine.