What is True?

by Guest Poster Mission Bicycle Company

True [troo]

adjective: "Look how well that wheel spins, it’s perfectly true."

verb: "Look how wobbly that wheel is, it needs to be trued."

A true wheel is one whose rotation is in alignment, free of any wobbles (side-to-side) or hops (up-and-down). It’s easy to check for, just lift your wheel off the ground, pick one spot to watch (at the brake pad is easiest), and give it a spin. If it wobbles back and forth like the one below, it’s out of true.

What’s Going On?

Wheel building is a bit of alchemy. A light aluminum hoop is joined to a hub by steel spokes. Each spoke is essentially a fancy bolt, and is threaded into the rim with a small nut called a nipple. Next, the magic happens. The wheelbuilder tightens each spoke/nipple combo to create over 50 lbs of equal tension per spoke. When complete this collection of elements, weighing a couple pounds or less, can carry a heavy human all over creation.

Let’s repeat that phrase “equal tension,” because its absence is what creates the out of true wobble. It’s just like tug-of-war. When one spoke has a higher tension than the adjacent spoke on the opposite side of the wheel, the spoke with higher tension will pull the rim to one side. You want both teams (i.e. spokes) to be evenly matched so it’s always a tie. When one wins, your wheel loses at being true.

All wheels have the capacity to lose true, but hand built wheels on high quality rims will endure the intended abuse of commuting better, and for longer. This is why at Mission, we build custom bikes with Velocity Deep V's built one at a time.

What to do?

A less than true wheel is never going to fix itself and will in fact likely get worse. As it does, proper brake alignment, stopping power, and structural integrity will all be compromised. In short, get it trued.

A Velocity wheel in the truing stand.

Truing wheels can be one of the more advanced repairs possible so if you don't want to tackle this yourself, expect to part with your bike for a day and $15-$30 (per wheel) forever.

Tutorial: How to True a Wheel without a Turing Stand