This is my understanding as well.

Once 2-3 spokes on the same wheel break, AFAIK the most prudent course of action is to rebuild the whole wheel. Otherwise you will, as you have done, keep breaking spokes on that wheel.

It's also a bit unclear who is replacing the spokes, what tools they have available, how good is the mechanic in question.

Thanks for all the replies. The problem has solved itself: the rim broke, and I bought a new wheel with 36 spokes. I don't want to speculate why it broke, there might have been a few other reasons besides the spoke problem. Probably everything combined.

I've got just one more question. The bike shop only had road bike rims, narrower then my old rim. The tires seem to fit ok (they're 1.6 inch), and the new rim looks much stronger than the old one. Should I expect any problems with it just because it's narrower? I'm thinking about the bad roads again.

I would ride more gently. That can go a long way in saving rims and spokes. High speeds and aggressive riding on rough roads with a fully loaded touring bike can be a recipe for overstressing the wheel, cumulative metal fatigue, and accelerated kaputitude.

Seriously, a rider whose riding style is gentler on the bike can make wheels (among other things) last way longer. It's the accumulated hits (especially the harsh ones) that eventually add up to the point of too much fatigue, and doing things in.

A lot of it can be avoided by simply adopting some new approaches or riding habits -- slowing down, choosing your lines more carefully, taking it especially easy on extra rough sections of road, etc.

As far as the narrowness goes: all else being equal, wider rims are more robust. That is not to say yours isn't good enough, though; and it even could be stronger than your old rim. A lot depends on the exact brand and model.

My guess is that -- if it is a decent model, and you ride reasonably carefully -- it could last you quite a while.

Be sure to check the spoke tension once in a while, and keep things well tensioned.

Also, if you tension the wheel so that it is offset one or two millimeters toward the non-drive side (rather than perfectly centered), you can equalize the tension quite a bit between the drive and non-drive sides. I've done this, and it has worked and lasted very well, with no noticeable effects at all on the handling. You could try it and see if it works for you.

Remember too that some brands of spokes are much more durable than others. DT Swiss is a brand to look for.

It would help if you can lower your tire pressure when you go off road. It might not be feasible because of pinch flats, but if you can it will help protect the wheel.

I'm afraid the problem will show up again, as the NDS spokes in my new wheel are very loose. Two were even completely loose after I had done about 100kms. Luckily on a paved road. The wheel has been built in a small family shop, the guy having a glass of beer next to him. The spokes are probably not DT or Sapim!

Is there a fool proof way of tightening the spokes that I could use by myself? I'm about to hit gravel roads again. The other option is look for another shop and rebuild the wheel, as I'm in a bigger city now. But it's hard to ensure the quality of service. They always do a bad job here knowing you will never return to complain. And I'm tired of thinking that this and that bike shop f***ed my bike up (has happened several times).

I drink beer while truing wheels, so I have no problem with that. The loose spokes, however, are a problem. Go back and have him retension the wheel. He should do this for free and very quickly --two days max.

If he won't do it for free, or won't do it well, raise a bit of hell. Get him to reimburse whatever he charged you for labor, then go to another shop and have them retension the thing. You do not need to rebuild the wheel yet, but getting proper tension on the spokes is imperative. Do it ASAP.

Yikes, that really sucks. While it's possible to retension a wheel just using the frame and brakes as a makeshift truing stand, if you've never built a wheel before, it's likely that you'll make the problem worse. I would try my luck with a local shop.

But, if you're feeling adventurous, loosen all the spokes so that they're completely slack, and follow this guide starting at "Initial spoke adjustment"

http://www.sheldonbrown.com/wheelbuild.html

Instead of a truing stand, you'll have to use your rear triangle. Loosen the brakes so the loose wheel has room to move, then as it comes into shape, tighten the brakes and use them to check trueness. Again, if you've never done this before you're likely to jack up your wheel. I would still take it to a shop.

The guy is on tour in Patagonia. It sounds like he's pretty far from the original shop, and even if he wasn't, I'm not sure raising a stink and demanding refunds is going to get you very far at some backwoods shop.

It's tough when you're touring and doing your own work, because you don't have a tensiometer. I agree with rhm, that it's almost certainly too low spoke tension. Your drive side spokes are under more tension, so are stretched more, so don't loosen. Straight gauge spokes are more difficult to get just right, because they don't stretch as much, so there's a greater tension change in a smaller length change.

All your spokes on the non drive side are probably fatigued and should all be replaced. Easiest to do them all at once. I'd replace all of the spokes on both sides with the same, butted spokes - they're cheap, so replace the new ones, too, and tension up the whole wheel. Your NDS spokes want to be at least as tight as your front spokes, or better, find a shop with a tensiometer.

This is crazy. You will either end up with an undertensioned front wheel or an overtensioned rear wheel. *DS* should be about the same as the front, and both should be at whatever the max tension for the rim is.

http://www.sheldonbrown.com/wheelbuild.html

If you go to section "half-radial spoking" there is a good answer to my original question, why the left side spokes were breaking in my old wheel.

I love the idea of that, but the reality is the standard spoke pattern works just fine if properly built. Spokes don't really mater all that much, what matters is wheel build and spoke to hub fit. Brand or type is way down the list, for the first few hundred thousand miles.

Other versions of the half radial idea are wheels built with thinner spokes on the non-drive side. Or one side straight one side butted.

Stress relieving spokes is a good method to lengthen spoke life, there are a lot of methods. Start with cold setting heads gently setting the heads in the hub like a finishing nail. Mak sure the spokes are bent to the right angle over the rim. Take parallel pairs of spokes and squeeze them till you hear some shifting. put the wheels hub down on a carpet or board and lean fairly heavily on opposite sides of the rim, as if putting a stiff lid on a garbage can. Do this all the way around and on both sides. You should hear the spokes pop free of the rim. I think sheldon had a method of using pry bars or something. This is part of the process of getting spokes up to full reliable tension and reducing fatigue failures at the hub.

Another thing that is supposed to wear out spokes is that people thread them on certain hubs so that the bend is in a radiused hole. Some hubs have no counter sinks, some have counter sinks on one side only. On those hubs it is bad to put the bend where it exist the counter sunk side, it should dig itself a channel on the sharp looking side. That said, some of the fancy hubs I have all CNC machined etc... have counter sinks both sides so it can't be all that terrible (advice assumes alloy hubs).

By the way, another thing not to worry about is your weight or the 32 spokes thing. Should be fine on the front wheel only, would be fine on the back on 26" wheels. 36 is just better.

No, I am not crazy. I have been building my own wheels for a while and they hold up better than factory or LBS wheels, and they are built to the rim manufacturer's spec, which might have something to do with that.

I just went out and measured spoke tension on my tandem, conventional 36H Velocity rims, because this bike is loaded like a touring bike might be and has145mm rear dropouts. My Park tensiometer reads ~19 on the front spokes, ~20 on the NDS spokes, and ~21 on the DS. Velocity specs 105-115 kgf for front wheels and 110-120 kgf for rear wheels, so I'm in the range, which might have something to do with the reason my tandem wheels stay true and don't break spokes. I built these wheels a couple of years ago.

On my single with Rolfs for another instance, Rolf specs 140 lbs. front spoke tension and 180 lbs. DS tension.

You are incorrect.

You've cherry-picked some nice corner cases there, which I respond to below, but the real point is that NDS and front tension don't have anything to do with each other. There is a spec for tension that applies to DS rear and front, or one for each. NDS is whatever is necessary to get the dish right. On a typical modern wheel, NDS tension will actually be a fair amount less than the front tension. On more exotic wheels, it might be greater, but it's not a sign of a better (or worse) wheelbuild as long as everything else checks out.

With a 145 mm OLD, there's very little dish in that wheel. With a typical 130-135mm hub, your NDS tension is not going to be so high. Also, I don't know what gauge spokes you're using, but based on those readings either your DS is overtensioned or your front is undertensioned (at least according to the specs you quote).

I've never seen that drastic a difference in spoke tension for front and rear, but I admit I have no experience with paired spoke and/or low spoke count wheels. In any case, I'd bet that the NDS tension is less than 140.

What if I tighten all the left side spokes by 1/2 turn, and then apply the seating and stress relieving steps from the mentioned article? Would that help?

Given what you've described, a quick fix like that is liable to make things worse. What does the right side tension feel like? Say, compared to your front spokes.

edit: Also, is the wheel true (not rubbing the brake pads as it rotates) and dished correctly (centered between the dropouts. You can gauge this by sticking your fingers between the rim and the seatstays).

edit2: If the DS tension is not super high, and the wheel is generally true and dished correctly, then here is an option. If there are any NDS spokes that are totally loose (rattling around), tighten them just enough to take the slack out, but don't put any tension on them. Then put 1/2, or even a whole, turn on *every* spoke. (Just doing one side would move the rim.) I would still press my luck with a local mechanic, but at least if your wheel goes all wobbly or doesn't track straight, then it's not too hard to undo your changes.

I used the tandem because I don't have an MTB, the tandem's wheels are much more highly stressed than any touring bike, and because the OP hasn't told us what his dropout spacing (DOS) is. However, if he's running 32H touring wheels and 1.6" tires, it seems to me there's some possibility that he's got 135 DOS. Never heard of a road tire dimensioned at 1.6". And that tire is sure not going to work on a 15mm road rim.

But even if he's running 130 DOS, I think you'd be wrong in your original assertion about tension: if he tensions his DS the same as his front, his NDS will be too low. On a 130 rear DOS bike, the front tension should be between the DS and NDS tension. All my road bikes are like that, and I never break spokes. A tourer trying to tension a wheel has to have something to go by, and plinking the front spokes will give him that, assuming that the front wheel was originally built correctly.

That's all he has to do: bring the rear tension up until his spokes are all tight, the wheel is round, and the wheel is dished correctly, i.e. rim same distance from the brake pads when inserted normally and 180° from normally. Then plink the rear spokes and the front, and adjust all rear spokes by the same amount, a little at a time, until the front plink is between the rear plinks in tone. Then readjust the dish, which will now be a bit out.

Spoke tensions are a little like tire pressures. We try to get them to come out to spec, but there's going to be some variation, which I attempted to indicate by the "~" symbol, and there is a good bit of leeway in the exact tensions. You're right that the NDS spokes on the Rolfs measure at less than 140 lbs. I should have gone out and measured them, instead of only relying on Rolf for info.

I was surprised when I emailed Velocity to find they build all their wheels to the same tension regardless of size or spoke count. The park converted numbers are about what CFboy mentioned, so his wheels are dead on. One of the advantages to building with quality stuff is one can get a manufacturer's recommendations for the the tension.

Here is an article that relates tension to musical pitch. While this might be more difficult than a gage, it might be fairly easy to establish on the run in SA, and also as a method of checking tension of adjacent spokes. It is possible to have fairly divergent tensions even when the wheel appears to be true.

Depends on the wheel spec, and in most cases it's a small difference. For example, Mavics have the same spec for both wheels. Even with the Velocities, there is only 5 kgf difference between the two ranges. On the other hand, with a 135 mm wheel, NDS will be about 70% of DS. Use your "NDS >= front" and one of those wheels will be off by 30+ kgf. That's a recipe for disaster.

This is a (mostly) correct statement, but it's irrelevant. There is a spec for DS tension and front tension, and often it's the same or about the same. NDS is whatever it needs to be to make the rear wheel true and dished. The relationship between NDS tension and front tension doesn't matter.

Waste of time. If the wheel is already in ok shape, just bring up the DS to where it should be (same as or slightly higher pitch than front), and then adjust the NDS, and maybe the DS if the rim is borked, to fix the dish or true. You don't need to check the NDS tension as you go because it is entirely determined by the DS tension and the geometry of the wheel. That's why it's crazy to make any statement about what NDS "should" be.

What gauge spokes did you use? Looking at the Park table, for just about any gauge, one of your wheels is off 10-20 kgf. I'm not saying that your wheel will fail because of it, but the only reason your NDS spokes are tighter than your front spokes is because you built one of the wheels out of spec.

It isn't that hard to learn this. And once you do, you won't have to be at the mercy of these dodgy bike shops.

You need a spoke wrench with the right fit. Make sure it's good and snug; otherwise, you can ruin the nipples. Spoke wrenches come in several slightly different sizes, for different nipples, and you want the right one for the nipples you are using.

Carry some extra spokes, just in case (the best quality you can find down there).

Once you develop a feel for it, it isn't that hard to check and adjust the tension.

You want the tension to be even on each side. The NDS will be looser; but the spokes should still be well tensioned, and as close as possible to equal in tension all the way around.

You can pluck the spokes and get an approximation -- all spokes on the same side should sound the same, or as close as possible.

You want to avoid loose spokes. They fail much sooner.

As you gain experience, you will also develop a feel for how tight they are, and how tight they should be. If you grip a pair of spokes in a 'handshake' grip, and squeeze, you can feel the deflection, and the resistance to deflection (this is how most tensiometers work). After a while, you just get a feel for this, and you can use it in addition to the plucking method.

It helps to find some good, well-built, well-tensioned wheels. Pluck the spokes. Squeeze and deflect. Gain some familiarity....

It isn't that hard; you just need some hands-on experience.

********
If you take a couple of pieces of thin, bendable wire, and attach one end to the back of the rack, near the rim, and then make a small loop on the other end, and bend the wire so the loop is very close to the rim, it can serve as a guide for truing the wheel. If you position it near the outer edge of the rim, it can also serve to gauge the roundness of the wheel -- so you have both left-right, and in-out gauges; and if you repeat on the other side, you have gauges for both sides. I just leave these wires in place (after bending them just a little bit, so they are out of the way), and they are ready to be used whenever needed. You can check your wheels easily at any time this way.

You can hang the bike from a sturdy tree branch or some other support, using parachute cord, rope, straps, or whatever you have. Or you can flip the bike over.

Good luck with it, and please let us know how it goes.

Well miki150 ....... I feel the pain you're in . I don't know how much you'll be able to help yourself or not, and I can't offer you anything to help you currently, other than in the future..... either learn to make your own wheels... which may or may not be as simple as it sounds...... or seek a truly professional wheelbuilder. I don't know what country you're from, but they're around. In the US, Joe Young is my favorite. Peter White, Gravvy Wheels and Rich Lesnick at Rivendell are all good also.

Once you experience a superbe set of wheels, you will never settle for less. Most people, however, have never seen a superb set of wheels, as pre-made and LBS wheels cannot match the work of dedicated pro. Not an absolute, but in general.

Yes, I'm definitely going to learn how to build a wheel. In fact I'll take the whole bike apart and put it together again when I get home.

I don't want to use a bike service ever again, I haven't had a single good experience with any of them. I think each bike shop that I've taken this bike to has broken something in it.

I think I'll only do another 700km on this trip, so I'll just go with what I have. I'll by a few replacement spokes for the new wheel. They are all new spokes, so should last me that much, even if they're not tensioned correctly.

Yes, my point in trying to help out the OP by checking tension by pitch and going off his front wheel.

I was also surprised to see the Velocity info back when I started building wheels. Spoke tension varies quite a bit as the wheel rolls. Suprisingly, the greatest spoke tension is in the spokes on either side of the contact patch, not on the top spokes. In any case, if all the spokes are to remain tight as the wheel rolls, even those at the contact patch, they have to be stretched during the initial build. So my guess is that Velocity figures their wheels will be built with 14-15 butted spokes and these tensions adequately stretch those spokes, so their rims are designed to support these tensions. Hence the number of spokes doesn't matter. They're not being tensioned to support a load, but rather to stretch the spokes.

The interesting thing about the Rolfs isn't the variation in spoke tension, it's the level of tension - very low compared with a traditional build. 140 lbs, which is only 64 kgf. So much for the talk of how all low spoke count wheels are in high tension and apt to fail! My guess is that either Rolf's spoke material stretches more easily than the usual round steel spoke and hence required less tension, or perhaps the stiffness of the rim allows much less change in spoke tension as the wheel rolls, hence less stretch is required. However that may be, the Rolfs require the least attention of all my wheelsets.

And in any case, stretch those spokes! That's what keeps them from breaking.

Oh . . . and this stretching business is the reason that wheels built with heavier spokes are not stronger than those built with normal spokes, which is an appropriate thing for a tourer to be aware of. Heavier or unbutted spokes at the rim's specified tension will have less stretch. 10 spokes at 110kgf = 1100 kg/wheel! Don't need more strength than that.