How long should spokes last?

Question

Trek Fx 7.3, 1 year old, 1900 miles

3 days short of my 1 year bike purchase anniversary I discovered some broken spokes on the rear wheel. The bike shop gave me a new wheel they had in the shop, an extra wheel they had and said it was better than my wheel. There was no charge for this I presume because it was under a year and though I'm not sure I would guess Treks warrenty is 1 year. 2 weeks later another spoke breaks and I replace that at a 30 dollar cost. The "sales" person tried to sells me a $160 wheel saying that factory wheels are junk and this expensive one is so much better.

This morning which is about 3 weeks from the last spoke, another spoke breaks. I commute to work and this is becoming a problem. I probably need a new wheel but I'm debating whether I want to bother with this shop anymore.

Any thoughts? thanks

Answer 1

This largely depends on how frequently you check the true and tension of the spokes. If one gets loose you are likely to break spokes frequently, and once you've had a few break the others are likely to go more frequently.

As part of my daily pre-ride check I spin the wheels looking for significant wobbles and will take care of them right then.

As part of my monthly check (usually the first weekend in the month) I squeeze pairs of spokes together around the wheel to check that the tension is approximately the same. If spokes are loose or if the wheel is out of true I remove it and use a truing stand to true it up.

My general rule of thumb has been if I've broken 4+ spokes it's time to have the wheel rebuilt, which at my LBS cost me about $60-80 depending on the quality and quantity of spokes I choose.

Breaking spokes is not usually a reason to need to buy a new wheel unless there is some kind of defect in the rim or the hub.

Answer 2

So, there are several reasons which can cause spokes to break continually. Metal Fatigue is one, but it should take longer than that to be as serious a problem as it appears that you have.

They will also break if there is damage to the wheel in some fashion. Meaning if you hit a speedbump at reasonably high speeds, and the rim gets out of true, even if you true and tension it again, it may need more attention for the rest of its useful life.

If you break one spoke, and replace it, and the problem goes away, then you're fine. Breaking 2 or 3, or more, spokes on a wheel in a reasonably short period of time, especially if it is without apparent cause, like hitting something, is usually an indication that the wheel is permanently damaged and needs to be rebuilt or replaced.

This can also be the result of poor maintenance practices. A basic wheel should be trued and tensioned properly again after the first 100-200 miles of riding, and may need to be retensioned regularly to stay strong (at much longer intervals, like say every 6 months when ridden regularly). This interval will vary depending on rider weight, riding style, and skill. If this is not done, it allows the poorly supported rim (because the spokes are loose) to flex and bend as you ride, and even if you later tension the wheel again, it will not be as good as it was new.

The economy of scale in the USA and Europe means that it is often cheaper to buy a good prebuilt wheel than it is to have a handbuilt wheel made for you, even if they use the same parts.

I would think about where and how you ride the bike, and whether it is possible that you could be causing the damage in some way, and I would find a different shop with a good reputation, and ask them the same questions. If you get similar answers, then you can trust that the shop you are going to is doing well for you. Most shops do their best, in my experience, but not all shops have similarly skilled and knowledgable staff.

Last, there are definite quality and durability differences between a good wheel, even a good basic wheel, and a cheap factory built wheel of the type that would come on a sub $500 bike. What wheel do you have? What bike? If we know that I can help more directly, but these are good general rules to follow.

Hope that helps.

Answer 3

There are a few factors not mentioned here:

• How much do you weigh?
• Do kerbs get taken to?
• Are the broken spokes on the cassette side?

These factors come into play with the general question.

Out of the specifics you gave, sadly the Bontrager wheels on Trek hybrids are not the best and are most definitely prone to spoke breakages.

The sales guy you 'spoke' to probably knows this due to what gets booked into the workshop.

Answer 4

I have seen a situation where a internal-geared hub is used with a standard rim, and the (large) diameter of the hub results in the spokes approaching the rim at a fairly sharp angle (made worse by this being a 26" bike). This results in excess fatigue at the nipples and resulting spoke breakage there. Not sure how to fix this other than to get a new rim with angled spoke holes.

Answer 5

Spokes fail mainly due to poor wheelbuilding.

A properly built wheel has all spokes in equal and high tension, and every single spoke has been stress relieved. Such spokes last essentially forever. We know the author of The Bicycle Wheel, Jobst Brandt got as many kilometers from spokes as can be expected from a typical car engine.

Of course material faults sometimes lead to new spokes breaking, but most often it's due to the poor quality of the wheelbuild.

A thing to think about the $160 wheel: it has been probably factory built too. Factory built wheels can be turned by an experienced wheelbuilder to good quality wheels by stress relieving and tensioning the spokes to an equal and high tension. However, often times expensive "boutique" wheels have design faults in them such as not using rim with double eyelets, not using butted spokes but instead using straight gauge spokes, using hubs with cartridge bearings as opposed to cup and cone bearings, using less than 36 spokes per wheel, etc. Obviously these design faults can only be corrected by building a completely new wheel, but if a factory built wheel does not have these design faults, an experienced wheelbuilder can turn it to a good quality wheel.

Answer 6

I asked something similar here:

Why am I breaking a ridiculous number of spokes?

tl;dr: I was breaking a lot of spokes even after replacing and retruing, and it is not unlikely that you need to replace your wheel.

Also, someone correct me if I'm wrong, but $30 to replace some spokes seems like a lot, and it's a relatively trivial task. If you can your hands on some tools and find a guide (or, ideally, someone who has replaced a spoke before) you can do it yourself and feel all wonderful and confident and walk around your house with oil on your hands like its the blood of a buffalo and you can give yourself a Native American sounding name like Spoke Foot or Grease-in-his-hair.

I'd go with Spoke Foot, it's got a good assonance to it.

Answer 7

To actually answer the op question,which I had to go looking for, they'll last at least the life of the wheel. RoadbikeReview: Thread: How long do spokes last?