Frequency

When training a new technician on wheel building it is good to ask them what instrument they play. The tension of the strings on any stringed instrument results in a given note. A natural A note is 440Hz. A lot of instruments use string tension to determine the frequency of the note, you can do it with spokes if you want. If the learning tech tunes a guitar or mandolin as a hobby, they typically get the concept. Any stringed instrument for that matter.

In the world of wheel building the frequency of the tensions of the spoke vary depending on the wheel components. The tension will affect the note that resounds when the spoke is genly tapped with the handle of a small screwdriver. You can use a tire lever, a pencil, or stale bread stick for different tones.

Spin the wheel and let the stale bread stick gently tap each spoke as it goes by. Does it play a melody, or is it monotonal? Try the same thing on the other side. Turn your bike upside down if that’s necessary. For best results use a truing stand. If you hear something more melodic than Pink Floyd’s “One of these Days” you might want to fix that. The bread stick will still be good enough for most mechanics to eat.

A properly tuned bicycle has many frequency based forces it has to deal with. Brake bumps are the most prevalent example of those these days in the mountain bike world. They’re the washboard road of the trail. No matter, if you tuned your suspension to deal with it bike riding is an unequivocal great time.

Speed wobbles? Horrifying things that show up at the worst time? Yep, bad frequencies. Where do they come from? It could be a lot of things. If it were me, I would start with the wheels. On high speed road bike descents an out of tune wheel can really ruin your day. Add a little gravel to that and, hmmm. I just imagined myself scraping down Middle Cottonwood Canyon a little east of here. Tune up your gravel bike wheels. Jeez. You’re probably doing about 40!?!

For example: the frequency of light waves the color of this type emits contrasted against the background.

The difference between the two frequencies is what you’re perceiving now.