Dissecting The “Frame Rubbing” Problem

from Rookie’s keyboard

Hello, friends

I’m feeling unstoppable today as the song says and decided to write yet another post in my lunch break while the rest of the workers are losing brain cells watching TikTok and reels. I respect them. Don’t worry. They are all good colleagues.

Today, I will talk about the rear tire rubbing against the frame –  a turbo-annoying issue that usually occurs when the rear tire is inflated to the max in a narrow frame.

There are three possible points of contact:

a. The chainstays

b. The chainstay bridge (the little tube connecting the two chainstays)

c. The seat stay bridge (the small tube connecting the two seat stays)

If this problem is kept unchecked the expected results are:

  • Damage to the paint
  • Thinned-out chainstays that may fail (an extreme scenario)
  • Higher rolling resistance
  • Stress on the rim, hub, and rear axle

Dissection Of The Problem + Solutions

The first thing to check is whether the wheel is properly installed and seated into the dropouts.

If the frame has forward or rear-facing horizontal dropouts, the wheel can get tilted to one side.

Оpen the quick-release and pull the wheel backward while making sure that the rim is laterally leveled.

Old-school road bikes (some of the prime candidates to create this problem) have two small bolts at the back of the dropouts.

Note the tiny bolt coming out of the dropout

In the best-case scenario, those bolts are inserted an equal amount into the dropouts. Then, the rider pulls the wheel back until the skewer touches the heads of the bolts. 

That way the wheel remains straight after every installation and removal thanks to the reference points.

Vertical dropouts do not create this issue because the wheel does not have room to maneuver horizontally.

Vertical Dropouts

Still, check the wheel because it may not be fully seated vertically.

The Wheel Is Not Centered

There is a high chance that the wheel isn’t centered.

When that happens, one side of the spokes is pulling too much on the rim and positioning the wheel closer to the frame. If the case is severe, the wheel could rub against the chainstay.

Dishing gauge

To fix this, you have to redish the wheel.

The procedure is not complicated but requires some wheel-truing experience. 

To get the wheel away from the chainstay, you have to reduce the tension of the spokes on the rubbing side, increase the spoke tension on the opposite side, and re-check the overall spoke tension in the end.

This can be done with the bike in the frame. Ideally, however, a dishing gage and a truing stand will be used.

The Tire Is Just Too Big

My road bike came with massive tires. When I put the bike in a repair stand, I saw that the rear wheel was rubbing against the chainstay.

Re-dishing the wheel helped but didn’t eliminate the problem because the tire was simply too big for the frame. For that reason, I switched to 28mm tires for a while.

Wide tires increase not just the side profile of the wheel, but its overall diameter too. Thus, a wide tire could rub against the chainstay and the seat stay bridge too.

The Wheel Is Not Round

The wheel has to be trued laterally and radially. The lateral truing minimizes side-to-side movement. If that condition is not met, the wheel could rub against one of the chainstays.

Meanwhile, radial truing ensures that the wheel is round. If the wheel is shaped like an egg, and the tire is fairly big, the wheel may hit the seatstay or the chainstay bridge.

Wheel truing isn’t easy, but it’s not as mystical as a beginner might think. 

You can get the wheel true in the frame by using either the brake shoes (if the bike has rim brakes) or a set of zip-ties strapped around the seat stays and the seatstay bridge and use them as gauges.

Damaged Rim

A bent rim due to a fall or a hit, could also cause rubbing.

In that case, you won’t be able to fully true the wheel regardless of how much you play with the spokes.

To fix the issue, you will have to re-straighten the rim. If that’s not possible, a new rim or wheel will be needed.

Wrong Size Wheel

It’s super rare, but it’s technically possible that the wheel on the bike is designed for a bigger frame.

The seller might have installed a wheel from another bike to make the machine look complete.

The only way to avoid this issue would be to check the bike in person or ask the seller for a video of the bike.

Obviously, if you’re buying new from a shop, this can’t happen.

The Frame Is Bent

It’s also possible that the wheel is fine, but the frame itself is bent due to external damage.

In that case, the frame will have to be repaired or replaced.

Until next time, 

– Rookie


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