Description Of The Problem. When the rider inserts more effort, the spokes (usually those of the rear wheel) make a pinging sound. In some cases, the sound will disappear quickly and never come back. In others, the sound may continue for longer or never stop.
Possible Sources Of The Issue
1. Loose Spokes
If the sound is ticking (repeatable), then more than likely one or a few spokes are not tensioned sufficiently. If that’s the case, the sound will not disappear as you continue to pedal. In fact, it may get louder. After all, spokes can’t re-tension themselves.
A single loose spoke is not a major point of failure, but it’s not an issue that should be ignored either.
It’s fairly easy to find the problematic area:
1. Start grabbing pairs of parallel spokes. Continue until you find a pair that feels loose or significantly under-tensioned.
2. Once the pair is isolated, grab each spoke with two fingers and move it back and forth.
3. Tighten the spoke nipple with a spoke wrench until it feels as tense as the other spokes on the same side of the wheel.
Note: Overtightening the spoke(s) could easily bring the wheel out of its round shape and create rubbing between the brake shoes (if you use rim brakes) and the rim. That’s why it’s recommended to be conservative when performing the procedure. Start with 1/4 turns.
It’s also recommended to check the wheel’s trueness once you gain access to better working conditions in case you’re performing the procedure in the wilderness.
FAQ: What spoke wrench do I need?
Spoke wrenches come in different sizes depending on the spoke nipples. If you don’t know the nipple size, you can get a multi-wrench.
Stay away from poor-quality wrenches as they’re made of soft steel that will damage the spokes over time. Do not use the wrong size wrench even if it works initially because it will round the nipples.
The nipples are made of soft material (aluminum or brass) and are very susceptible to damage. Once a nipple is damaged, it has to be replaced because you lose the ability to tighten or untighten the spoke with a spoke wrench. The replacement process is not incredibly difficult, but it’s still tedious because you have to remove the tire and the rim strip.
Don’t forget that some multi-tools have a spoke wrench on them for emergency uses.
Also, do not use pliers, unless that’s the only option, as they will ruin the nipple’s walls very quickly.
2. The Wheel Hasn’t Been De-stressed After Building or Truing
If the sound isn’t ticking, has no rhythm, and is less predictable, the problem is more than likely a wheel that has been built or trued without performing a process known as destressing. The sound is similar to striking a guitar string.
Once a wheel is built, it has to be de-stressed to mimic the lateral stress that the spokes experience once the wheel is in use. The process could be compared to breaking in a shoe. Usually destressing is done by grabbing two pairs of parallel spokes and squeezing them with a lot of force.
If de-stressing is skipped, the wheel will be “pinging” significantly during the first ride. Usually, the sounds will diminish as pedaling progresses.
The same could happen if you’ve done a lengthy truing process to a wheel or if you have recently replaced a spoke.
Note: Slight “pinging” can happen even if the wheel has been de-stressed properly. That said, the intensity is much smaller.
3. Friction Between Dirty/Corroded Spokes
Bicycle spokes are made of very durable steel and can perform as intended for many decades. That said, over time, the upper layer corrodes. A 40-year-old wheel looks notably different than a new one.
When the wheel is rotating, the spokes that are connected to the part of the wheel that’s in contact with the ground flex. The flex creates friction between the spokes of the wheel that cross each other. If the spoke is corroded, the friction is greater and a sound may be produced.
Corroded spokes are not necessarily unusable. I have 40-year-old spokes on my retro road bike. If the spoke’s structure is intact, it can operate just fine. However, the layer of corrosion could create unnecessary friction. In that case, the solution is to put a drop of oil at the point where one spoke touches another.
4. Cracked Rim
Unfortunately, the source of the problem could be a cracked rim. If the rim develops a crack, it loses integrity and becomes more flexible during riding. This has a direct effect on the spokes too.
A cracked rim is not safe to ride and should be replaced immediately. Rims are not meant to be repaired and represent a consumable, especially when the rider uses rim brakes.
5. Cracked Frame
The chainstays of the frame are among its weakest spots. If a chainstay is partially cracked, it can also create a repeating sound augmenting when the pedaling effort increases. Thankfully, this is rarely the case of the problem.
If the frame is cracked, the most logical solution is to replace it. Frame repair is rarely if ever worth the trouble unless the frame has exceptional value for the rider, and he doesn’t mind spending a lot of money on its “resurrection”.
6. Bottom Bracket
It’s possible for a sound to be heard from one location even though the source is different. In this case, the bottom bracket could be the culprit.
The bottom bracket is a mechanism consisting of bearings and a spindle allowing smooth rotation of the cranks. If the bearings are worn or broken, the bottom bracket will begin making unpleasant sounds. Very often the sound will be permanent and will not disappear completely as the ride progresses.
The bottom bracket is fairly easy to diagnose. Disconnect the chain and try to rotate the crank arms. If the bottom bracket is rotating smoothly and quietly, it probably isn’t the source of the problem.
If the bottom bracket is difficult to rotate, it should be replaced or serviced. Truth be told, most bottom brackets today come as a cartridge unit and are not meant to be serviced.
7. Faulty Pedal Bearings
The pedals could be the source of the problem too. If a bearing is broken, the pedal would skip and may create a clicking sound. However, in this case, you will probably feel the skipping with your foot. Hence why I put this possibility last.