My spokes break, and break, and break
 

I seem to break spokes a lot. Even through three wheel rebuildings, I continues to break spokes. In the last 2800 miles I've put on my bike, I've probably broken close to a dozen spokes. I'm a big guy (6'2", about 215lbs), but not huge. The only thing that has remained constant through my rebuilt wheels has been the hub. I've completely replace the spokes and rim more than once, and spokes still break. Generally the spokes break near the hub, but they have sheared off by the rim at least once. It's always on the back wheel.

My bike is a steel Gunnar sport. I've tried some deep Alex Rims and now have an Mavic MA3 rim.

Is there a possibility that the hub is a culprit? I believe its a 105 hub, but it's a little worn and hard to read. It came with the bike when I bought it. Do you think the people I have building my wheels could be making some systemic error?

I'm not sure what to do. Should I try a new hub? Move to rims with more spokes? I think I have 28 hole rims right now. Should I move to thicker spokes? The ones I have now are 2mm spokes.

If the spokes have insufficient tension, they will move, and eventually break (usually at the flange). How have your other builds been in terms of reliability (and durability)? I would have thought if the hub was bad or worn, then it might fail, but that would be a failure of the hub, most probably at the flange; I don't see how a bad hub would cause a spoke to fail. The spokes might have been put in backwards; look carefully at the spoke holes; some (but not all) hubs have countersunk holes, and it's important to make sure that the spoke elbow is on the countersunk side. How's your building technique? You didn't say what lacing pattern you were using or what sort of riding you were doing; but with your weight and only 28 holes, it sounds to me as if you might be better off with a 36h x4 or at minimum a 32h x3 pattern. Need more data…

FWIW -

- Wil

Is another constant that you are doing the wheel builds? I don't mean that to sound pointed, but there could be something wrong with your technique (or whoever is building these for you).

The tension has always seemed to be very good. I'll have to get back to you, but I'm pretty sure it's a 4-cross pattern. The spokes have been breaking through all the builds.

My riding is about 50 miles a week on paved roads/bike paths.

I have had the same shop building all these wheels. They're pretty baffled about it. They have been giving me free rebuilds since I seem to be having such an odd problem. I trust them and they say that none of their other wheels have had such problems.

I'm 230lbs, and have about 1600 miles on my latest set of custom built wheels without issue. I have a 24 spoke radial up front, and a 28 spoke 2x/3x in the rear - both laced to niobium alloy rims.

So - your weight should not be the issue, and I doubt it's the hubs.

What kind of spokes is the shop using? How're the road conditions where you ride, and how's your riding style?

You might try an inexpensive Open Pro 32x set from Performance to see if anything changes.

BTW - another tip might be to ask your builder to use brass washers on the spokes, since you're using a well-worn hub…

Also, you might want to use double-butted spokes…

- Wil

PS: How do you get x4 with a 28 hole pattern? I've always thought the max. # of crossings is determined by dividing the number of spokes by nine. If this number is exceeded then the effective flange diameter will be reduced and the spokes will overlap the heads of others.

I'm probably just wrong about the x4 then. I'll check more carefully when I'm not at work.

You may try lacing it to velocity deep v's 32 or 36 spokes. There's no use in boutique wheels with low spoke count. They just look good.

The Gurd Schraner (sp?) book on wheel building that I read recommended the same thing. I've never tried it, but it makes sense. If the hub is worn and the spoke heads have ANY room to "move" in the holes, then the spokes are doomed before you start. Keeping those spoke heads from moving against the hub is the only way to keep them from breaking. The brass washers (being softer than the spoke & hub) are supposed to mold themselves to the hole in the hub, preventing motion when the wheel spins.

+1. The quality of the spokes isn't the only factor, but if they're low-quality spokes, that sure doesn't help matters.

Make sure the spokes are evenly tensioned (especially drive-side). Pluck them with the tire deflated and listen for a consistent tone. It should be pretty close to the same all the way around. If it sounds like a kid playing the piano with his elbows, there's your problem.

Reading some other replies, I don't think that 1K or 2K miles without going out of true is much of an indication of durability. That's like 1-2 months of riding for a lot of people. I guess failure or wobble in that period certainly indicates a durbility issue, but the opposite is not an indication of a durable wheel. Tell me about wheels you've been on for 10,000 miles and are still true. I built my Deep Vs up to last until the braking surface fails. I'm guessing I'll get 30,000 miles out of them. I'm 6'4" and 180-185, riding a pair 32h/36h 3x. I'm sitting at maybe 3000 miles on them now, and I still think of them as new. Of course they still pluck the same note all the way around.

Assuming the LBS is correct in that your wheel is the only one having this trouble, then I suspect they may be using poor quality spokes. Perhaps they have a bad batch of spokes in one of the two sizes used for the wheel. If the LBS is not using that size for other customers, they may be rebuilding your wheel with the same batch of spokes.

I would ask about having them use spokes from a different box or different brand. Best to have them use Wheelsmith or DT Swiss if they aren't doing so already.

I'll second the double butted 14-15 gauge spoke recommendation. I weight 200 lbs and have had to rebuild all my wheels with double butted spokes to keep them from breaking.

Are the wheels being totally rebuilt (take all spokes off, replace all spokes, rebuild wheel), or are they just replacing the spokes as they break? If the latter, make sure they do the former; once a spoke breaks, it is hard to get an even tension around the wheel without at least loosening up all the spokes and retensioning them all together.

Also, if it is the same person at the shop rebuilding the wheel, you might want to ask for someone else to give it a try. They might be doing it wrong or trying to get the work done too fast. A standard 32 or 36 spoke wheel (either 3 or 4 cross) should not break under a rider weighing 215 lbs. A dozen spokes in a season is waaaaayyyy to many. At most, a spoke every other year or so (failing from fatigue; something which is going to happen to heavy riders with any wheel) is the most you should tolerate.

Hmmm... remember that cross-patterns only help with torque-loads from pedaling, it doesn't do squat for vertical or horizontal loads. The actual amount of torque a human generates is pathetic compared to the weight-loading on the wheel. So the cross-pattern won't be much of a concern for your wheel here.

Weight is the bigger factor than torque and you can't possibly be overloading that wheel unless you're hitting speed-bumps at 50mph. When I weighed 245lbs, I rode 300-500miles/wk and did a tonne of bunny-hopping off kerbs and over pot-holes. I've bent the rear axle about once a year, but the spokes held up just fine.

The quality of materials and the build is very important. When rebuilding, it's imperative that the new spokes are laced into the hub in the same direction as before so that the depressions cut into the hub by the previous spoke is re-used. This spreads out the load across a larger surface-area of the elbow on the spoke. Using double-butted will give you some overhead as well since they stretch more for the same load. Thus they can take more displacement before losing all tension at the bottom where the rim flattens out. This springiness helps keep the wheel true longer since it's harder to untension the spokes and have the nipples rattle and untwist. Might help with fatigue life as well since the spokes never undergo full-tension <--> no-tension transitions with each revolution.

Here's the important question: "What is the actual tension used on the spokes?". Without that number from a tensiometer, it's impossible to say if the tension is "right" or "good enough".

What about your rear-wheels dishing? Measure the spoke-tension of all the spokes on the rear-wheel. Average the left-side spokes and the right-side spokes. What's the difference in average-tension between the two sides? I try to keep them at less than 15-25%, but have seen wheels with variations as large as 50% between the two sides. Note that the lower the overall tension, the greater the disparity between left vs. right side tension, so tension the wheel towards the high-end of the range for the rim you're using. Adding a longer axle and spacers to the left-side to move from 126 to 130mm rear-spacing reduces the dish and spoke-tension differences significantly.

Well, crossings help by applying tension when the spoke starts to go slack. If radial, a slack spoke is a slack spoke. For 3 or 4 cross, the loose spoke will be tensioned by the tight spoke crossing it (this is over a very short period, like when hitting a big bump). For low crossing patterns where the crossing spokes don't touch, there is no radial strength difference at all.

-Mike

If by bike paths you mean trails and not paved then you should be using 36 hole rims due to your weight and the fact your bouncing up and down on rougher stuff.

Your Sun rims are good rims but you should go with a 36 hole rim IF you want a strong dependable wheel rather then a light weight wheel. Velocity that one post mention is a very good lightweight rim as well as Sun and Torelli make very good 36 hole rims for less jack then Mavic, and are all at least as good as the Mavics. You could also go with a 32 hole rim on the front OR if your spoke breakage has been only on the rear then you could use one of your 28 hole rims for the front just replace your hub and spokes as discussed below.

You should also use DT Competition dble butted 14-15 guage spokes as another post mentioned.

You will need to replace your hubs of course if you go with a 36 hole rim, but the 105 hub is a very good low cost hub that is good enough for club racers to use! So if you want to keep the price of your new wheel down and still have a decent wheel get the 105's. If you decide to keep the 28 rim on the front then replace the hub since those 105's are cheap and you need to get new spokes and rebuild the rim anyway.

Obviously if you get new hubs then using brass nips becomes a mute point and going with (DT) alloy nips can save some weight.

You should lace the 36 and the 28 in a 3x pattern to get the most reliablity.

I use to race, but now that I don't lightweightness is not an issue reliabilty is since I ride into remote areas. So I use 36 hole rims all the way round to prevent headaches, but I only weigh 160-165 and never broke a spoke...except once when a stick caught one. Plus with more spokes if you do by chance break a spoke as I did that one time, you can simply twist the broken spoke around another (you might have to slightly readjust nearby spokes to get the rim back in true) and your going to be able to ride the bike home, whereas with lessor (28 and below) that probably will not happen since the wheel will more then likely taco on you. By the way I use DT Competition spokes on the rear and lighter DT Revolution spokes on the front and these wheels have over 35,000 miles on them.

Except that wheels built with the crossed spokes not interlaced yields no difference in strength or stiffness compared to ones with interlaced spokes. Remember that only the spokes at the bottom where the rim is flattened goes slack. The actual load of the weight is being spread out to all the other spokes that aren't in the contact area by increasing their tension by the same total amount of tension that the bottom spokes have relaxed. So the stressed spoke is not the one that goes slack, it's the others that's had their tension increase by 5-6%. By interlacing them, you might actualy be causing those tight spokes to even experience more load.

This is all academic really because the differences between interlaced or not on crossed or radial wheels really doesn't affect wheel-strength or longevity by much anyway. That would be ignoring all those other factors that really do contribute.

Go to:http://www.sheldonbrown.com/wheelbuild.html click on spoke patterns.

Thanks everyone for the replies. Sorry about taking so long to get back to this thread. My wheels now are 32 spoke, 3 cross. I think I'm just going to start over with a new wheel, 36 spoke, and good DT spokes. I'm going to the shop soon, so I'll check what kinda spokes they've been using.

I would keep the 32's and use for front, just respoke one of them with DT Comps and get a new hub and save the other 32 rim for a spare.

I didn't read these other replies, but a big man as yourself needs a 32 hole wheel. Now, when you're 5'4" and weigh 135, you can get away with the 28 hole hub, but above 180, you need the 32 hole. Also, have your next wheel [should you choose to have one built] built with DT spokes. We've had no problems out of those spokes!

[QUOTE=Wil Davis]BTW - another tip might be to ask your builder to use brass washers on the spokes, since you're using a well-worn hub…QUOTE]
+1 on that. Insert the spoke in the hub and check for play. There should be none. The little washers worked to solve a spoke breaking problem on one wheel I built. And they look so cool - I wonder if they come in gold? What a way to jazz up a wheel eh?

[QUOTE=toolboy]But why go through all the labor and expense (granted washers are cheap) to solve a spoke breaking problem due to worn hub holes when for about $55 for the rear and $35 for the front. Seems you might as well buy new hubs and eliminate playing the duct tape game to get the old ones to work.

Ot but not so long ago seen something on science channel talking about how bike rime spokes and bikes were much like suspension bridges. drawing a imaginary line between rear axel and front axel to show the "road desk" and the spokes above that line were the "cables" of the suspension bridge.

Might help some who have a hard time visulizing this premis to visulize it easyer. Esp helpful if your building your own wheels.