herst

Hi Everyone,

So after having my truing stand for a couple weeks and working on old wheels I had lying around, I decided to really go at it on the front wheel of my fixed conversion. The first thing I did was get spoke tension on the wheel totally equal using pitch. Honestly, its like a tweaker's dream, as the spokes approach consistent pitch you get all sorts of harmonics and alternate tones emanating from the rim.

After a bit of truing I took it on my first ride and the wheel made all kinds of pinging and creaking noises, and came a bit out of true. After searching the forums I learned it was probably because I hadn't stress relieved my wheel. So I searched around on stress relieving techniques and settled on doing what Sheldon describes here:

https://www.sheldonbrown.com/wheelbuild.html#seating

I even used the left crankarm from an old crankset. Now, after retruing, stress-relieving and hopping back on the bike, things were much less noisey, but there was still some pinging, especially while trackstanding.

Here's the quesiton: Sheldon's description is a bit vauge on the direction one applies stress to the spoke so can someone describe the proper technique? If I look at a pair of crossed spokes which make an X, I was applying pressure towards the point where they cross. Should I have been doing the opposite, i.e. shoving the crank arm in the middle of the x and forcing the crossed spokes away from one another? If I'm in fact applying pressure properly, am I just not applying enough pressure?

Thanks a bunch.

HillRider

Stress releaving should be done by grabbing pairs of spokes across the hub from each otherand deflecting them toward the center of the hub. What you are trying to accomplish is to realign the spokes so the bend at the heads is not under constant load, i.e. the bend should be deformed until the tension is at right angles to the spoke bend.

Also, some of the creaking and popping noises may be from spoke "windup" relieving it self as the tension changes while riding.

herst

Certainly a number of different techniques float out there. Initially I tried what you described but had some issues and then read the following:

https://yarchive.net/bike/stress_relieve.html

A good read. Specifically Jobst Brandt says the following:


I'm not a macho guy, and I program all day, so my hands are usually pretty tired at night, which was why I decided to use Sheldon's technique to stress relieve the wheels. I was just wondering exactly how this is done.

Al1943

I suggest that the pinging noises you are hearing are due to insufficient tension. Stress relieving ain't no big deal, it's like playing a harp aggressively.

Al

herst

Hmm, I'm pretty sure its not due to insufficient tension. When I compared the tension of these spokes after I was done truing and whatnot to the tension of my rear wheel, which was handbuilt by a mechanic two months ago, the front wheel's spoke are slightly more tense.

In fact, I'm actually more worried about having overtensioned the spokes.

Just curious, why would I hear pinging noises if the spokes weren't tense enough?

genericbikedude

I dunno. I've always put the wheel on the floor, rim on a carpet or some other softish surface, held the other side of the rim between my legs, and pressed DOWN hard. I rotate about 30 degrees and repeat until the thing stops popping. Then retrue. Has always worked great for me.

halfspeed

The pinging is because the spokes twisted when you tensioned the wheel. When a load is applied, spokes move. When they move, they untwist. When they untwist they lose tension. When they lose tension, the wheel loses true.

"Stress relieving" is a process of relaxing the internal stresses within the spokes that come from the manufacturing process and building the wheel. See the Brandt article linked to in this thread. This is not the cure for your problem so articles on stress relieving won't get it solved. Removing spoke twist is NOT stress relieving.

You can minimise the amount of twist during the build in the following ways:
1) Use straight guage spokes
2) Use eyeletted rims
3) Use brass nipples
4) Before lacing, apply a drop of light lube to each spoke hole
5) During the build, overshoot and then back off your tension adjustments to where you want them.

Once the wheel is built, you can remove the twist by holding the wheel like the steering wheel of a bus with an edge of the rim against your abdomen and pushing down on the sides of the rim with your forearms. Rotate the wheel and do it again. Flip the wheel and repeat. If you have overtensioned your wheel, this process will taco the wheel and likely bend the rim, rendering it useless.

halfspeed

If I may contradict myself, numbers 2, 3 and 4 in my list won't help with spoke wind-up much. They are good advice, but not so much for this problem. They make it easier to turn nipples against the rim but windup comes more from the spoke/nipple interface. Twisting spokes can be made to turn more smoothly by dropping oil at the spoke/nipple interface and allowing capilary action at the threads to draw it in.

Al1943

I didn't like No.1 much either, even though it is correct. Double butted spokes make a more durable wheel because the skinnier middle section absorbs more shock, protecting the more critical ends.

To avoid spoke windup all you really need to do is hold each spoke with pliars while tightening.

Al

Al1943

It is very unlikely that you would over tension a wheel.

Loose spokes often go ping ping, whether twisted or not.

On a well built conventional wheel set the drive side rear spokes will have the hightest tension, the non-drive side rear spokes will have the least tension, the front wheel spokes will have tension in between.

Al

halfspeed

I agree. How often in the cycling world do you get lighter and stronger at the same time?

That really shouldn't be necessary. Brandt doesn't like that suggestion and I agree with him:

https://yarchive.net/bike/spoke_twist.html

I'm not the only one I know who has done it. It's easier to do with cheaper rims which new builders are more likely to use. A friend tacoed a CR-18 with too much tension.

Rev.Chuck

When I stress relieve, I hold the wheel facing me like a steering wheel, grabbing it at around 11 and 1. I rest it against my elbows, at about 3 and 9, and hold the wheel against my stomach, at 6. Then I pull towards me with my elbows pushing away. I rotate all the way around the wheel, then do the other side. Be careful. You can taco the wheel if you use to much force.