Building a wheelset and using it made me realize that the things I vaguely knew were actually verified in practice, which was fun and helpful for handling equipment.
The most important thing when building or checking the condition of a wheel is to maintain the external alignment of the wheelset while ensuring that the spoke tension is as uniform as possible.
After building wheels several times, I learned that even if the lateral true (left and right) and radial true (up and down) are not perfectly aligned, it is better not to touch them as long as the tension is within a uniform range.
The reason why tension needs to be uniform is that when drive torque or braking torque is applied, if the tension of a particular spoke is excessively high, the excessive tension on that spoke will momentarily exert strong force, increasing the probability of breakage of the rim or hub.
Typically, the maximum tensile strength of a spoke is over 250KGF, so it is rare for a spoke to break due to inability to withstand the tensile force.
In most cases, the hub or rim is the problem. The maximum tensile force that a rim can withstand is around 180kgf, and the tensile force that a hub can withstand varies depending on the spoke pattern, but it is around 200KGF.
Therefore, when exceeding the limit of endurance, the probability of problems occurring in the rim or hub is higher than in the spokes.
The recommended tension when building a wheel is typically between 120-130KGF for the drive side and the front wheel rotor side.
The reason for this is that since the spoke tension constantly fluctuates under driving load or braking load, and the tire pressure reduces the tension by 20-30KGF on the drive side due to air pressure.
Of course, once the tension stabilizes to a certain extent, the rate of decrease in tension becomes smaller than initially.
The reason why the tension needs to be 120-130KGF is not only for a solid response but also to ensure minimum tension on the non-drive side with a large angle or the opposite side of the rotor. Since spokes have the characteristic of pulling on one side and relaxing on the other when loaded.
In this case, if the tension itself is too low, the tension will drop to zero momentarily and then repeatedly apply, leading to spoke loosening and fatigue failure. Therefore, it is important to ensure stable properties.
The uniformity of tension is also a crucial factor. If the tension deviation is large, the load on a particular spoke increases, and some spokes may have their tension close to zero, which is also undesirable.
Only when the tension is uniform can all spokes bear the load evenly.
The reason why exceeding 130KFG is not good is that in the case of disc brakes, when a sudden hard brake is applied, the tension on the pulling spoke reaches the rim's tension limit.
If it is too high, the rim or hub may break its durability limit. Conversely, if it is too low, spoke loosening and problems such as spoke breakage can occur.
Therefore, uniformity within the appropriate tension range is required.
In the case of rim brakes, the load on the spokes is only applied when pedaling, but in the case of disc brakes, the load is greater when braking than when pedaling.
Therefore, if a person with a heavy weight uses a wheel with too few spokes, the risk of breakage increases.
Of course, manufacturers make them well, but it's worth noting that cases of wheel failure have changed from the past.
Personally, when building wheels and touching some finished wheels, I felt that checking the tension intermittently for about half a season after opening the new product package is important.
The point where the new rim and nipple meet and the point where the hub and spoke head meet need to settle in place as the load repeats. Even if stretching is done well during the manufacturing process, I felt that the spoke tension decreases while driving.
Most finished wheels are the same.
However, personally, I think Campagnolo's wheelsets are the best in terms of initial completion.
Even after long use, there is hardly any change in tension.
The wheels I built myself and semi-maker wheels like Pasport or Elite have some differences in degree, but there is a significant decrease in tension when using new wheels. Therefore, it seems that maintenance is needed two or three times in between.
Stretching well can reduce the number of times needed by one, but even if you buy a new product, you need to check the tension intermittently until it stabilizes for about half a season or a season so that you can use it in good condition for a long time.
Finally, here are some tips when buying used wheels:
While most people can judge the appearance, trueness, and bearing condition without special tools, it is not easy to check if the spoke tension is uniform without experience or tools.
However, if you pluck a spoke with your finger like a guitar string and listen to the sound, it's safe to assume that the tension of the wheel is uniform if the sound is consistent between the drive side and non-drive side.
The higher the tension, the higher the pitch. The lower the tension, the duller the tone. Therefore, the drive side produces a high-pitched sound, while the non-drive side produces a relatively dull, low-pitched sound.
The problem is when checking the drive side or non-drive side, if a particular spoke sounds too high or too low.
Wheels that look fine but have large spoke tension variations are more likely to cause problems during use. So it's best to avoid such products.
