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Some years ago I used a rear carrier with a bundle buggy lashed on to carry stuff around. I had a problem with wheel wobble. I thought a rebuild as 4 cross (instead of std 3 cross) might help. The guy in the shop where I bought the spokes noticed a cracked rim (actually both front & back). After I rebuilt the back wheel 4 cross with a new rim, the wobble was gone. Don't know if the 4 cross fixed it, as I don't know how long the rim was cracked.

I am thinking of building a cargo trailer, and am wondering if anyone has any knowledge on whether rebuilding a wheel to 4 cross for the additional stability it may bring (the old bike is long gone) is worth the effort for short trips with 50-60 lb of freight. the trailer would be attached to the rear axle, not the seat post.

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  • The main advantage to 4-cross is that the spoke is tangential to the flange, so the stress on the flange is much less. I doubt that wheel wobble would be reduced, and, in fact, it might be made worse. (As Moz indicates, 50-60 lb is a relatively trivial amount of weight compared to, say, this 230 lb rider.) Jun 22, 2014 at 0:11

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I would not bother. But then, I would not bother with 4 cross in the first place. Spoke count matters more - a 24 spoke racing wheel is just not designed to be used for load carrying. What I think is important is (in order) 32 or more spokes, a properly built wheel, a decent rim, and a decent hub. You can do a lot just with a properly built wheel because if the spoken tension is nice and even even a relatively low-quality rim will not be stressed past its limits.

I've carried a lot of heavier things and built a few load bikes and trailers over the years. Especially with a trailer, 30kg is not a particularly heavy load. For the rider, loads under half your body weight should be easy for anyone who rides regularly. Your main issue is likely to be lateral forces on the rear wheel, and the way to reduce those is riding style. I would leave buying a better rear wheel until after you have problems with your current one. Largely because you probably won't have problems with it. Unless it's a low spoke count wheel, in which case I suggest getting a second hand steel frame MTB and never using your racing bike for lowing a trailer if you can avoid it.

Also, FWIW, I found towing a trailer with 30kg of stuff on it quite hard on a fixie. If you're going to do that, at least make sure you have both front and rear brakes because stopping suddenly on a fixie is hard enough as it is, adding a trailer just makes it worse.

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  • Also, my trailer recipe might be helpful when you're thinking about trailer building.
    – Móż
    Jun 21, 2014 at 22:40
  • Towing on a fixie? Seriously?
    – Batman
    Jun 22, 2014 at 1:06
  • @Batman turned up to an event, a friend was towing stuff on a fixie, they got quite sick, I rode their bike home. It wasn't my idea, is what I'm trying to say. I think it's stupid.
    – Móż
    Jun 22, 2014 at 3:04
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None of the hubs I have used recently (Shimano XT, Dura-Ace, 105, and a few OEM ones I had kicking around) can be safely built 4-cross because each spoke would interfere with the spoke head of its first crossing spoke. This adds an unnecessary challenge to building the wheel and makes the wheel weaker than it needs to be.

The number of crosses makes almost no difference to wheel strength. Things that do make a big difference:

  • Use 32- or 36-spokes.
  • Use double-butted spokes.
  • Ensure the spoke tension is even and as high as permitted by the rim you are using.

High tension gets more important the more load you are putting on the wheel.

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