Wheel truing: how to take out the bends and bumps in a rim

News

HomeHome / News / Wheel truing: how to take out the bends and bumps in a rim

Jun 12, 2023

Wheel truing: how to take out the bends and bumps in a rim

If you want to give wheel truing a go, you need a few necessary tools. The most

If you want to give wheel truing a go, you need a few necessary tools. The most important is the correct spoke-nipple wrench for your wheel. If you have flat-bladed spokes, you need a spoke holder to keep them from twisting as you rotate the nipples. While having a truing stand lets you do this job with greater speed and accuracy, it isn't necessary for basic truing. You can leave your wheel in the bike and use the brake pads for reference pointers or the end of a blunt tool, such as the handle of a screwdriver, held up by the rim.

Before beginning your first truing adventure, look for any cracks or broken spokes and nipples. Sometimes the rim might be permanently damaged: no amount of spoke tension will cure that stubborn hop. At this point, it is best to take the wheel to a professional mechanic to assess. The rim might need to be replaced and the wheel rebuilt.

If you do want to true, find an old wheel that you can practise on. You can sometimes seriously hurt a rim by truing improperly.

First, lubricate the nipple threads with penetrating lube or oil. Rotate the wheel and squeeze each pair of spokes with your hands. See if you can feel any really loose ones. Tighten these ever so slightly and inspect the rim area where the loose spokes were located.

Lateral Truing

A lateral truing adjusts the side-to-side orientation of the rim. It's an easier fix than a radial true and more important for brake performance. Begin by rotating the wheel in the bike or truing stand. Set up your pointer close enough to the rim so that you can hear any "scrapes," the moments the rim touches the pointer. Find the highest spot causing the scrape. At the scrape spot, adjust spokes that will pull the rim away from the reference pointer. If the rim scrapes your reference pointer on the right side, you must tighten the spoke or spokes that attach to the left flange of the hub. Sometimes, you might also need to loosen the spoke that pulls the opposite side as well to get the rim to move. Use small, quarter-run adjustments to the spoke nipples until the rim no longer scrapes your reference pointer. After each twist, rotate the wheel. Look and listen to ensure the side-to-side movement is lessening. Once the wheel is relatively straight, you should "de-stress" the spokes. Place the wheel on it's side on the floor or a bench. It should rest on the side on the floor or a bench. It should rest on the side of the hub. Push down on opposite sides of the rim toward the ground. Rotate the wheel an eighth of a turn, and push down again. Repeat until you’ve done a couple rotations. Flip the wheel and repeat the process.

If you hear tinging sounds, that's the nipples seating into the rim. After de-stressing the spokes, put the wheel back into your bike or stand and rotate and repeat the truing steps once again if the wheel needs it.

Radial Truing

Radial truing address any deformities in the rim that go away from or toward the hub affecting the rim's roundness. This adjustment tends to be more difficult than a lateral true. If a section of the rim runs away from the hub, you must tighten the spokes in the centre of the deviation to move the rim closer to the hub. Make changes "in pairs:" adjust a left and right spoke by the same amount. If these pairs don't keep the same amount of tension, you will pull the rim out of lateral true.

Twist Right

The threads on a spoke are right-hand threads. But, when you are turning a spoke nipple, the old phrase of "righty tighty, lefty loosey" doesn't apply. In fact, left (counter-clockwise) tightens and right (clockwise) loosens. You must think of the spoke as a threaded rod (bolt) and the nipple as the nut. Visualize screwing on the nipple from the inside of the rim with a screwdriver, and then place your hand on the spoke wrench and twist.

Lateral Truing Radial Truing Twist Right