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I have a Miyata "Three Ten - Red Head" model road bike, but both front and rear wheels are not the original wheels for the bike.

There is no name, size or marking of any kind at all on either wheel.

The only information I know for sure is

  • they have 27 x 1 1/4 inch tire's with 36 spokes on each wheel
  • the rear is running a five speed cassette setup
  • Chaintrings are Shimano BioPace Triple ( 50/44/28 ) crank setup

Other than that, I don't have a lot to go on to help me figure out the correct size spokes and nipples to order.

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    are you rebuilding the wheels you have, replacing individual spokes, building new wheels altogether or what? Jul 29 at 1:22
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What's your goal here?

If you have a broken spoke, take out a good one from the same side of the wheel, and measure it. Note the front and rear wheels may have spokes of different lengths, and the rear wheel normally has longer spokes on the left-hand side of the bike.

If you don't have any spokes, just a rim and a hub, then there are spoke length calculators to help with all the geometry required. Examples:

Enter the same measurements into several calculators and make sure they agree.

You will require a vernier caliper to get accurate-enough measurements - a ruler is not sufficient. Micrometers can work but you need to be creative.

In the end, spokes will come in differences of 1mm or 2mm, so round to the nearest whole number, or if you have double wall rims then round up.


Nipples are easier - buy brass ones and get a pack of 40 or 50 per wheel. Spares are good to have, and aluminium nipples are not durable. Do use the correct sized spoke tool - a spanner is not the right tool.

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  • I would actually advise not always rounding up. Some dealers only stock 2mm increments. If you fully screw a nipple, the spoke head protrudes only 1.4mm. Note that fully tightening it, the spoke stretches, as much as 0.8mm for triple-butted spokes. So if you measure when untensioned, you have only 0.6mm flexibility for rounding up. I would put that at 0.5mm for safety. So round at most 1.5mm down, round at most 0.5mm up.
    – juhist
    Jul 29 at 9:02
  • But if you have an ERD that is intended for "tensioned spokes" (so it's 1.0mm - 1.5mm less than ERD for "untensioned spokes"), then when getting results from a spoke length calculator, you may round 1.0mm-1.3mm up and the rest goes to rounding down. How much you can round up depends on which spoke thickness was used to take into account spoke stretch.
    – juhist
    Jul 29 at 9:07
  • @juhist fair point - its hard to know if a slightly long spoke is better or worse than a slightly short one. And a full set of spokes is surprisingly expensive. I'd prefer to have to shorten the spokes rather than put up with a too-short one, so erring on the longer side.
    – Criggie
    Jul 29 at 11:58
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Focusing only on single vs double butted spokes: I am not sure that the distinction is very important in your case.

In the bicycle industry, butting means that the wall thickness of a tube or the diameter of a spoke varies across its length. Usually, the ends will be thicker, since that's where you need more material - this applies to frame tubes and spokes. Single butted means that the tube is thicker only at one end, and double butted means that it is thicker at both ends. Triple butted tubes exist, and I believe that for frame tubes this means the thickness is further reduced in the center.

All the major spoke manufacturers offer straight gauge spokes, which have constant thickness, e.g. 2.0mm thick is common. Double butted is also common, e.g. 2.0mm thick at the threaded end and at the j-bend, 1.8mm in the center. This previous question discussed the pros and cons of double butted vs straight gauge spokes. I am not sure if you meant double butted vs straight gauge or not.

Single butted spokes do exist. One example is the Sapim Strong, which is 2.3mm thick at the j-bend, and 2.0mm thick everywhere else including at the threaded end. (NB link goes to a commercial site and may not be durable; the principle should remain and I believe that DT Swiss, another major manufacturer, should offer equivalent spokes, as well as other spoke manufacturers.) The asserted benefit is that this is stronger and more suited for heavy duty applications like tandems, e-bikes, maybe really heavy duty MTB applications. I'm not a wheelbuilder, but I think many breakages that are not a result of poor building or spoke quality control may occur at the j-bend, so if true it could make more sense to put more material there.

Additionally, I have a feeling that most single butted spokes may be 2.3mm at the j-bend. From my perspective as an observer, I did not see spokes with that diameter in use with rim brake road bikes during the 2000s to 2010s. I have a feeling that extra strength is unnecessary. Disc brakes impose more torque at the hub, so it could be sensible to have spokes that are 2.3mm at the j-bend in that case - but I don't think that diameter is universal on disc brake drop bar bikes either. I am including this commentary about rim brake road bikes because that is what the OP has.

More generally, as discussed in the previous answer, you could just use straight gauge spokes, which are cheaper. They may be less comfortable, and the conventional wisdom is that they are less durable than double butted. However, a big part of a wheel's durability is how many spokes compared to the rider + bicycle + load weight, how strong the rim is, how straight the rim was when it was delivered, how well the wheel was built. Chances are that 36 spokes are sufficiently strong if the wheel was built well. If you went with double butted spokes, there may be a theoretical durability advantage, but it may not matter in practical terms. For a rim brake bike, the sense I get is that as long as the spoke is 2.0mm at the ends, it's strong enough (quality factors discussed above aside).

As to how to tell how thick your spokes are, you could obviously use a pair of digital calipers to measure the spokes at the center and both ends. If you have the same thickness throughout, you have straight gauge. Same thickness at both ends but thinner in the center = double butted. Thickest at the j-bend but same diameter everywhere else = single butted. I am not sure if non-digital calipers will suffice suffice for this, because they may only have a precision of 0.1mm. In any case, I don't think it is important to measure the diameter of your current spokes; you need to know their length, and you can select a double butted or straight gauge spoke at your leisure - and yes, you could choose to use a single butted spoke for disc brakes if you want, I just don't see a strong rationale for this.

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