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Just that, what kind of wheels use spoke washers?

Is this a nice addition to any old wheel, or are certain rims designed to use these? Would these perhaps help with a damaged spoke hole in a rim?

I'd guess you would not normally want to use these with rims not designed for them, because it would elevate the nipple head into the space occupied by the tube and tire.

enter image description here

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Spoke washers are used at the hub end, between the flared out cap and the hub itself. The intention is to take up extra length between the bend and the end, to help prevent the spoke from breaking. Common use is on hubs with thin flanges (for lightweight or because they're cheap) and on heavier loaded bikes to spread the load.

Notice how the lower spoke is snugged closer to the hub? The upper spoke is more likely to break sooner.

enter image description here

The nipple washers are for spreading the load at the rim end of the spoke. You're right that the washers have to fit inside the rim track/valley but that's so they lie flat against the inside of the rim, rather than touching in two places and focusing the stresses. Again, touring bikes or load bikes would be the place to find these. Race bikes wouldn't have them.

Nipple washers are used to allow the spoke to leave the rim at a strange angle. Normally the spoke leaves slightly away from 90 degrees (pardon the pun) so the nipple is not flat against the rim, and the spoke is under a slight bending load.

Here's a rim with large domed washers that let the spoke stay straight. I think this might be a motorcycle rim, but the concepts are the same. enter image description here

If you have a damaged spoke hole, a washer may help, but its a judgement call about how much damage you can safely ride on. If the spoke nipple fits through the nipple hole, I'd not ride on it even with a washer, because all you've done is put the load on a stamped washer then onto the edge of a damaged hole in the rim.

Would you trust this rim if it had a 2c flat washer below the cracked piece? A curved rim washer would just make it worse. enter image description here

Tubeless tyres take away the worry of pressing on the washer - here's an extreme example on a fatbike wheel: enter image description here

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    Nipple washers can also be used to take up slack in the spokes if they're too long, but this is a bit less than ideal.
    – Will Vousden
    Commented Mar 9, 2017 at 9:23
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    @criggie I know social-nicety comments are discouraged, but that's really an extraordinarily useful and informative answer, with the pictures and all.
    – compton
    Commented Mar 9, 2017 at 9:34
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    Wouldn't only every other spoke need the washers due to the lacing? For example those pointing widdershins and cross the others below? Splendidly written answer!
    – gschenk
    Commented Mar 9, 2017 at 10:59
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    There is an argument made, by one of the wheel gurus, that spoke manufacturers make the elbow of standard bent spokes longer, to make life easier for automatic lacing machines. Thus this extra length is unneeded (and makes spoke failure at the hub more likely). And lots of wheels, especially those with large multispeed hubs, have the problem of bad spoke angle at the rim, leading to spoke failures at the nipple. Used to be that rims were often drilled at alternating angles, to help alleviate this, but I've not observed it lately.
    – Daniel R Hicks
    Commented Mar 9, 2017 at 12:50
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    Some nipples have spherical contanct surfaces designed to make it more likely that the spoke will follow the desired angle at the rim, at least with an eyeletted rim: dtswiss.com/Technology/Nipple-technology Rims with the (non-eyeletted) holes drilled at an angle for hub gears do still exist: cyclingabout.com/review-rigida-andra-30-rim
    – armb
    Commented Mar 9, 2017 at 17:17
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For most of the last 50 years, higher quality rims had steel eyelets at the spoke holes to distribute stress and double-wall rims had ferrules that were crimped by the eyelets and which distributed the stress of the spoke to the outer wall, as well. Mid-range, double-wall rims would sometimes have the eyelets without the ferrules. Adding this extra steel (later stainless steel, to control oxidation) added some weight, but even racing rims typically had them. More recently, we're seeing a lot of manufacturers ditch the ferrules and even the eyelets. I cynically think this has a lot more to do with marketing and lack of consumer awareness paving the way for manufacturers to avoid the additional expense of adding these features, rather than from an engineering standpoint. Consumers seem less concerned about rim and tire weight than they used to be. There are newer theories that rotating weight on the rim and tire is not as significant from a performance standpoint than once assumed, but this may be biased to support the push towards wider tires and rims. I've noticed that the thickness of the aluminum extrusion seems to be much greater on modern rims than back in the 1980s and 90s, especially on racing rims, and the thicker walls are likely more resistant to cracking from the stress of the spoke nipple than in the past. I suspect that ferrules also make it more difficult to seal the rim tape in tubeless systems. Riders seeking to reduce rim mass tend to be more interested in carbon fiber rims, anyway, in spite of all the problems that material introduces. Bicycle component performance is much more about customer perception than engineering reality.

Building with nipple washers is a bit of a pain and can easily double the time it takes to lace the wheel. Still, I would suggest adding spoke nipple washers on most non-eyeletted wheel builds. Some popular rims, such as many DT models, don't have eyelets, but I think they get away with this more through marketing and brand recognition than through superior engineering.

One more thing--eyelets do not always equal "better." Back in the 1980s, Mavic went through a time when it seemed that they were incorrectly crimping the eyelets and this resulted in tiny stress risers that resulted in a whole lot of rims cracking at the spoke holes.

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  • Nice answer. Thanks for sharing your experience, and welcome to Bicycles Stack Exchange.
    – compton
    Commented Jan 14, 2018 at 15:40
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    Thanks for the answer. It would benefit from editing a little however. Would you explain the difference of ferrules, eyelets, and washers? In large parts it also reads like a rant and is somewhat repetitive. An edit to make it more concise would really help here.
    – gschenk
    Commented Jan 14, 2018 at 15:45
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    The effect of rim mass can be calculated with high school physics and hasn't changed. It's just that the people who misunderstood it have found new things to rant about.
    – ojs
    Commented Jan 14, 2018 at 15:50
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    Part of the reason that rim eyelets fell out of favor was because of the popularization of deep-section V-shaped rims, which naturally have a lot more metal at the spoke hole. I'm not sure if that fully mitigates the absence of eyelets, but it does go some way to.
    – Adam Rice
    Commented Jan 14, 2018 at 16:26

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