The more you remove of these spokes, the lighter your wheels will be. It is pretty apparent when you see it written out like that, isn't it? There is an issue though, and that is you still need the wheels to be able to support weight and to transfer your power. You need to find a balancing point between lightweight and strength. You have to design your rims, hubs correctly, and spokes to work together to balance these ideals. That is why our road bike wheels tend to feature 20 spokes on the front and 24 spokes on the rear.
We use more spokes on the rear as the wheel has to be able to cope with the torque you are providing. We will be talking about spokes in a forthcoming spokes article so be sure to check back for that. We now need to tell you about our Aero series wheels.
Our Aero range took where our Fast and Light series went and made the wheels lighter, around g per wheelset since you asked. One of the ways we managed to achieve that was in a redesign of our front hub. We took our R13 hub and managed to create a stiff hub flange that was lighter and allowed us to drop down to 18 spokes on the front wheel.
We still use 24 spokes on the rear wheel as we want your power to transfer to the road. You will still be wanting light wheels for your road bike even if it has disc brakes. Disc brakes though add another force to your wheels. Disc brakes are powerful, and without a super stiff wheelset, you will feel your wheel twist under braking pressure. So you still need a superlight wheelset, but it has to be built more stiffly. The more spokes you have, the more this effect "tapers" - the unloaded spokes unload less, the loaded spokes load less.
Take an extreme case of an 8 spoke wheel, with paired spokes at 12, 3, 6, and 9 o'clock. When the wheel is loaded with bike and rider, the spokes at 6 o'clock are taking all of that unloading between just two spokes.
The spokes at noon are getting bone tight. Then imagine the same wheel but with 20 spokes. More spokes in the "unloaded zone" will unload, but that amount will be distributed over more spokes, so each one feels less unloading.
That's what that's all about. Put enough load on that rim and it's Taco Tuesday. Not that we or anyone else builds wheels to that extreme well, Spinergy did , but the extremes highlight the effects in play. Asymmetric rims mitigate the danger of unloading spokes because they give the less tensioned spokes of the wheel more tension to start with, but we'll talk about offset rims more either tomorrow or Friday.
If we get through that process with about the right answer, then the type of spoke should matter relatively not that much. We use CX Rays for most of our builds, because our answer to the first part usually leaves us in a place where CX Rays are a great tool for the job.
And, quite honestly, from a sales perspective swimming upstream sucks and you never have to apologize for using CX Rays. We've worked hard to lower our cost on them and reduce the premium we charge for them to a point where they're easy to justify.
For builds where you're trying to hit someone's budget number or where it just doesn't make as much sense to use CX Rays, then there are others. When we know we've got plenty of spokes as it is, we can build with Lasers. D-Lights are a bit more spoke than Lasers, but they're still light and great to work with. Race spokes 2. They're easy to build with though CX Rays are the easiest and can add some "oomph" to a wheel's strength, but as a builder I prefer working with lighter spokes which I can't fully explain.
Even if we don't do the math on this for every single build which we don't , those are the methods behind the madness. And having put that out there, I sort of weep for my inbox's future.
AC — I have to plead ignorance on that one, they were always a co-leader with DT through our time. Make sure you are turning the nipples the right way. When you work with a screwdriver, it is easy to figure out which way tightens the screws, clockwise. It gets confusing when you start using the spoke wrench, because now you are working from the back side of the clock!
Once there begins to be a little bit of tension on the wheel, you should start bringing it into shape. There are 4 different things that you need to bring under control to complete the job: lateral truing, vertical truing, dishing, and tensioning. As you proceed, keep checking all 4 of these factors, and keep working on whichever is worse at the moment.
You can see the irregularities in the rim as you start to true the wheel, but as it comes more nearly into shape, you can listen to the scraping of the truing stand's feelers against the rim for a more sensitive adjustment. High-end truing stands have dial indicators, though these are not really necessary. Try to make your truing adjustments independent of each other. For lateral truing, spin the wheel in the stand and find the place on the rim that is farthest away from where most of the rim is.
If the rim is off to the left, tighten spokes that go to the right flange and loosen those that go to the left flange. If you do the same amount of tightening and loosening, you can move the rim to the side without affecting the roundness of the wheel.
After adjusting the worst bend to the left, find the worst bend to the right, and adjust it. Keep alternating sides. Don't try to make each bent area perfect, just make it better, then go on to the next. The wheel will gradually get truer and truer as you go.
For vertical truing, find the highest high spot on the rim. It takes a larger adjustment to affect the vertical truing than the horizontal truing. Vertical truing should usually be done by tightening spokes, gradually building up the tension in the wheel as you go along. As soon as the lateral truing gets reasonably good within a couple of millimeters start checking the dishing. Put the adjustable feeler of the dish stick over the axle on one side of the wheel and adjust it so that both ends of the dish stick touch the rim while the middle feeler rests against the outer locknut on the axle.
Then move the stick to the other side of the wheel without re-adjusting the feeler. If the dish stick rocks back and forth while in contact with the outer locknut, the spokes on that side of the wheel have to be tightened to pull the rim over. If the ends of the dish stick sit on the rim but the feeler won't reach the locknut, the spokes on the other side of the wheel need to be tightened. When the dish is starting to get within 1 or 2 millimeters of being correct, go back to working on the lateral truing, except now you will not be alternating sides.
If the rim needs to move to the right to improve the dish, find the worst bend to the left, adjust it, then find the new worst bend to the left, and so on. All the time you are doing this, you need to keep checking the vertical truing, and whenever the vertical error is greater than the lateral error, work on the vertical.
A rim may be a bit irregular at the seam -- usually directly opposite the valve hole -- see Machined Rim Sidewalls. If the rim is welded, grinding away excess metal may have left a slight hollow. If the rim is pinned, the ends may not line up perfectly.
You may need to relax your truing standards slightly at the seam, average the vertical truing for the two sides, or guide by eye on the underside of the rim. You also need to keep monitoring the tension on the freewheel-side spokes. There are three ways to check tension. One is by how hard it is to turn the spoke wrench. If it starts to get hard enough that you have to start worrying about rounding off the nipple with the spoke wrench, you are approaching the maximum. Fifteen years ago, this would be the limiting factor, and you would just try to get the wheel as tight as you could without stripping nipples.
Modern, high quality spokes and nipples have more precisely-machined threads, however, and now there is actually a possibility of getting them too tight, causing rim failure. The second way of judging spoke tension is by plucking the spokes where they cross and judging the musical pitch they make. If your shop doesn't have a musical instrument or pitch reference, and you don't have perfect pitch, you can compare it with a known good wheel that uses the same length of spokes.
This will get you into the ballpark. Before I started using a spoke tensiometer, I used to keep a cassette in my toolbox on which I had recorded my piano playing an F , a good average reference tone for stainless spokes of usual length. The third, and best way is with a spoke tensiometer. Every well-equipped shop should have one.
Average freewheel-side tension should be up to shop standards for the type of spokes and rim being used. More important is that it be even. Don't worry about the left-side tension on rear wheels. If the freewheel side is correctly tensioned, and the wheel is correctly dished, the left side will be quite a bit looser. You should still check the left side for uniformity of tension.
Using thinner spokes on the left side avoids most of the problems which the looseness causes -- also see John Allen's article.
As the wheel begins to come into tension, you start to have to deal with spoke torsion. When you turn your spoke wrench, the spoke will first twist a bit from the friction of the threads. Once the nipple has turned far enough, the twist in the spoke will give enough resistance that the threads will start to move, but the spoke will remain twisted. What a good wheelbuilder can do that a robot machine can't do is feel this twist. If you "finish" your wheel up, and it is perfectly true in your stand, but the spokes are twisted, the wheel will not stay true on the road.
The twist in the spokes will eventually work itself out, and the wheel will go out of true. This problem can be prevented by sensitive use of your spoke wrench. You need to overshoot and back off. This is much easier to do on straight-gauge spokes, because they are stiffer torsionally, and it is easier to feel the twist than it is with butted spokes.
Before a wheel is ready for the road, it must be stress-relieved, because the bend in the spoke has to accommodate itself to the shape of the hub flange and vice versa, and a similar process may go on where the nipple sits in the rim. Some wheelbuilders do this by flexing the whole wheel, others by grabbing the spokes in groups of 4 and squeezing them together.
My preferred technique is to use a lever to bend the spokes around each other where they cross. My favorite lever for this is an old left crank:.
This particular technique has the added advantage of bending the spokes neatly around each other at the crossing, so they run straight from the crossing in both directions. As you go around the wheel this way you will probably hear creaks and pinging sounds as the parts come into more intimate terms with each other. After you do this, you will probably have to do some touch-up truing, then repeat the stressing process until it stops making noise and the wheel stops going out of true.
Jobst Brandt , author of the excellent book The Bicycle Wheel , points out a less-obvious benefit of this stressing of the spokes:. After cold forming, steel always springs back a certain amount spokes are entirely cold formed from wire. Spring-back occurs because part of the material exceeded its elastic limit and part did not. The disparate parts fight each other in tension and compression, so that when the spoke is tensioned, it adds to the tensile stress that can be, and often is, at yield.
When spokes are bent into place, they yield locally and addition of tension guarantees that these places remain at yield. Because metal at or near the yield stress has a short fatigue life, these stresses must be relieved to make spokes durable. These peak stresses can be relieved by momentarily increasing spoke tension and stress , so that the high stress points of the spoke yield and plastically deform with a permanent set.
When the stress-relief force is relaxed, these areas cannot spring back, having, in effect, lost their memory, and drop to the average stress of the spoke.
The "trailing" spokes pull harder under drive torque to make the rim turn, and the "leading" spokes contribute by pulling less hard under driving torque. Each group of spokes contributes equally in its own way to turning the rim to keep up with the hub.
Derailer rear wheels should be laced with the trailing spokes running up along the inside of the flange. There are three reasons for this:. Note: This is not an important issue! There is a sizable minority of good wheelbuilders who prefer to go the other way around, and good wheels can be built either way. Conventional "semi-tangent" spoke patterns are indicated as "cross 3", "cross 4", etc.
For example, cross 3 means that each spoke crosses 3 other spokes that run from the same flange of the hub. Most wheels are built cross 3. Higher cross numbers cause the spokes to leave the hub flange more nearly at a tangent. This makes them better able to withstand the twisting forces of hard pedaling in low gears, and also braking forces from hub brakes. Lower cross numbers make the spokes more nearly perpendicular to the hub flange, and to the rim.
In the case of the " radial " cross 0 pattern, the spokes go straight out from the hub without crossing at all. Lower cross patterns use shorter spokes, so they are slightly lighter, and they can also be slightly stronger side-to-side.
The more spokes a wheel has, the higher the cross number for a similar spoke angle. In the case of unusually large hubs, particularly large hubs in small rims, fewer crosses are often indicated, to avoid bending the spokes where they exit the nipples. For example, the Rohloff Speedhub has 32 spoke holes, but is usually laced cross 2. For extremely large hubs such as electric-bicycle hub motors, you may need to use a special spoking pattern.
We have an article describing how to do this. Radial spoked cross 0 wheels have the spokes going straight out from the hub. This pattern is suitable only for front wheels that don't use hub brakes.
There are two things to watch out for with radial wheels. Because the nipples point straight inward from the rim, they can turn more easily in most rims than when they are bent to a slight angle by a semi-tangent spoke pattern.
This ease of turning increases the risk of their unscrewing themselves on the road. Or, if a rim does not have recessed spoke holes, the rim tape and air pressure in the inner tube will keep the spokes from turning -- at least with a high-pressure tire. The other potential problem with radial wheels is that the spokes, trailing straight outward on the hub flange, can possibly rip the outer edge of the flange right off along the line of the spoke holes.
This is most likely to happen with small-flange, 36 hole hubs, because there is less metal between the spoke holes. If a used hub is re-laced radially, the notches left by the old spokes can act as stress risers, further weakening the flange. Many hub manufacturers specifically recommend against radial spoking for this reason, and will not honor warranties on hubs that have been spoked radially. Some folks will say that no bicycle wheels should be radially spoked for this reason, so do this at your own risk.
In my experience, it's generally OK with good-quality hubs that have forged shells. Back in , unaware of these issues, I built a front wheel for my tandem with 40 radial spokes on a medium-flange, "boutique" hub with machined flanges. After a few months of use, the wheel mysteriously went slightly out of true, and I trued it. I might better have taken the loss of true as a red-flag warning. One day, I just happened to be sitting on the floor next to my tandem, glanced at the front hub and noticed a crack extending along the line between several spoke holes.
I had been foolish, and I was very lucky. I rebuilt the wheel on a large-flange hub, using the same spokes in a semi-tangent pattern, and I have ridden that wheel for 30 years since without any problem.
If you ever notice a radially-spoked front wheel -- or, actually, any front wheel -- mysteriously going slightly out of true, stop, get off the bicycle and call for a ride home or to a bike shop. If you want to take your chances and try a radial-spoked front wheel, I would advise avoiding using thick spokes and very high tension.
Since front wheels are generally pretty trouble-free compared with rears, you don't need super-high tension on a front wheel that uses a reasonable number of spokes. If you use thin spokes, you can raise them to their optimum tension without their putting undue stress on the hub. Bicycle folklore has it that radial-spoked wheels give a "harsh" ride, because the shorter spokes are less "stretchy" than the longer spokes used in semi-tangent wheels.
This is hooey! Drive wheels and wheels with hub brakes should never be radially spoked. Due to the near-perpendicular angle of the spoke to the hub's tangent, any torque applied at the hub of a radial-spoked wheel will result in a very great increase in spoke tension, almost certainly causing hub or spoke failure. To protect the guilty, I will not say who built it. No, it wasn't Sheldon. A friend and I inspected the bike. He held the front brake and pushed down on a pedal with his foot.
The spokes of the rear wheel changed angle noticeably, pinging as they rotated in the spoke holes of the hub, and ringing with rising musical pitch like an electric guitar when the player pulls up on the tremolo bar. More and more rear wheels now are built "half-radial" with semi-tangent spoking on the right side and radial spoking on the left. Radial front wheels offer mainly esthetic benefits, but half-radial rear wheels can be substantially more durable than conventional ones, if the wheel is highly dished.
The high amount of dishing with more and more sprockets has caused an increase in spoke breakage on the left side of rear wheels. This is caused by metal fatigue. Just as you can break a paperclip by bending it back and forth a few times, you can break spokes by flexing them back and forth by a much smaller amount, millions of times -- even if they don't flex enough to take a permanent set.
A bicycle wheel turns several hundred times per mile. In miles, it turns more than a million times. A spoked wheel relies on having all of the spokes in constant tension.
A highly-dished rear wheel starts with very light tension on the left side spokes. The torque of hard pedaling combined with cyclical weight loading can cause the left-side "leading" spokes occasionally to go completely slack.
Repeated cycles of tension and slackness cause these spokes to fatigue at the bends, and ultimately break. With half-radial spoking, the amount of dish is very slightly less to begin with if you run the radial spokes up along the inside of the flange "heads out.
In fact, if you have an old wheel that has been breaking left-side spokes, "half rebuilding" the wheel into a half radial will solve the problem once and for all. I used to think that this was exotic, cutting-edge technology, until I happened to look at a couple of Model A Fords in a local parade. Their wheels were highly dished inward, and were laced in the same half-radial pattern, for the same reason.
A flip-flop rear hub, or one with a disk or drum brake, must resist torque on both sides, and should never be laced half-radial unless it has a large-diameter, one-piece shell.
Also, I don't think that the Ford wheel is half-radial for quite the same reason as a bicycle wheel. The outboard spokes of the Ford wheel attach to the hub at a much smaller diameter than the inboard spokes, and would change tension very little due to torque if in a semi-tangent pattern.
The Ford, like any dual-track vehicle, imposes large sideways stresses on its wheels when turning. The wheels at the outside of the turn also bear most of the weight.
The sideways force on these wheels increases the tension of outboard spokes at the bottom of the wheel, while the weight load decreases it. The large dishing angle of the outboard spokes tends to balance the increase and decrease in tension. The low dishing angle of the inboard spokes minimizes their decrease in tension. Ford engineers must have carefully considered all these factors as they designed this wheel.
Cutting-edge technology? No, the Model A was introduced in , 51 years after James Starley introduced the tangent tension-spoke wheel. There had been plenty of time for thought and experimentation. The Ford wheel has twice as many inboard spokes as outboard spokes, optimizing the tension despite the different dishing. Doubling the number of spokes on the right side of a bicycle wheel might also be used to optimize tension -- for example, a wheel might have 24 spokes on the right side and 12 on the left -- though at the expense of special rim and hub drillings.
These are not the only possibilities, but they are the practical ones. It you want information on whimsical patterns such as the crow's foot , et.
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