Determining Spoke Length for Wheel Building

  • 🎬 Video
  • ℹ️ Published 5 months ago

The procedure for determining spoke length when building a bicycle wheel.


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Video contents:
00:00 Video Start
00:25 Preliminary Info
01:21 Typical Tools
01:51 The Spoke
03:49 The Rim
07:11 Rim Offset
09:01 Hub Dimensions
12:01 Lacing Pattern
13:01 Differential vs. Non-Differential Spoke Lengths
15:02 Online Spoke Calculators

➤ Related Text Articles:

➤ Tools & materials used:
• Any Two Spokes and Two Nipples

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💬 Comments

I would happily pay Calvin to build me a set of wheels just for the bragging rights! "Why yes, my wheels were built by Calvin from Park Tool!" 😁👍

Author — Kent Cruse


The worksheet is a fantastic idea! I've built plenty of wheels but have never been systematic about recording the measurements, that's going to change now! Thanks!

Author — Short Name Cycling


Great video, this is really the hard part about building a wheel, in my opinion.

Author — John Hanley


This is perfect timing. I just bought a wreck for $10 that has a 3 speed gear hub and had a rear rim in pieces. Old enough I can’t just use the dt swiss calculator.

Author — Jonathan Z


You can find many rim erd's online. If you are replacing a crashed on rim, with an exact replacement, you can often use the old spokes if they aren't bent too much. You can even use a different brand rim, and the old spokes if both the old and new rims have the same erd (plus or minus 1 or 2 mm). 20 some years ago, I crashed a Mavic Cosmos rear training wheel and destroyed the rim. I checked the Mavic site and found that the rim was just a 28 hole open pro. I did some digging and found that a Sun M19 tubular rim had the same exact erd. I rebuilt the wheel with the tubular rim, and original spokes, and turned it into a good race wheel. After 20 years, the wheel is still bulletproof.

Author — MRGRUMPY53


Roger Musson's Professional Guide to Wheelbuilding. The only PDF I've ever bought in my life, and thoroughly worth it. Following it will hold your hand from zero to your first few sets of wheels.

Author — sabamacx


Nice. Concise. I've been doing this for years and it's nice to see it all in one place explained nicely. Aloha!

Author — G Matsushige


If you don't rely on manufacturers measurements you have the advantage of repeatability. When presented with different components you don't have to worry about the supplied measurements being measured differently. So measure yourself right from the start. Don't trust the manufacturer to know everything exactly.

Author — Mike H


Calvin is wise. If your lengths come out wrong, it's a product of your measurements. Different people measure slightly differently so they might need to build more than one wheel to really nail the lengths. I don't mean necessarily to measure differently or more carefully but just to see if you should round up or down your numbers to get better results. Or add a slight length correction to the spoke lengths before ordering.

Author — Mike H


Hi Calvin, I'm from Brazil. In a non-symmetrical rim, when measuring the difference from the center of the rim to the center of the hole, do I take into account the hole that is closest to the center of the rim or the hole that is furthest away? I participated in the wheels course at Escola Parktool Brasil and received your certificate. 😃

Author — Kleber Mecânico


I read somewhere that Calvin's mustache quivers when he's making a mistake before he even realizes he has made one. That's a primary reason he is so good at what he does. Like the hairs on our backs standing up if danger is approaching.

Author — GenghisKhanrad


Fantastic video! The best explanation I’ve seen on this topic! Great resource as I build. Thx!!

Author — Gone To Earth


Great tutorial! On some recumbent trikes the rear section frame is built asymmetrical. So instead of centering the rim between the locknuts it is centered between the hub flanges. How would that be calculated.

Author — Jim Barrett


Calvin, a very good explanation. Thank you

Author — Ted Lukins


I love these parktool videos it's like learning bicycle mechanics from Fank Zappa 🎸

Author — Luca Cotta Ramusino


Thanks for simplify this so even I can understand

Author — Ric Liang


Hello thanks, I was wondering, I have 24h front and 32h rear with dual and triple cross patterns respectively. Is it possible if I lace dual cross on the rear or triple cross on the front for compatible looks?

Author — XavierBetoN


I love your music, my favourite being Overnite Sensation, but I have even more mad respect for you now that you're building bikes. :)

Author — rudy pospisil


What role would the nipple length play in building wheels where the differential lengths were at 3 mm? Could one use alternating 2.0x12mm & 2.0x14mm while using the same length spoke?

Author — ChrisinOSMS 2002


Just an FYI
SpokeCalc will not accept smaller wheels (i.e. 16" trailer wheels). It returns an input error on the ERD field.
The UBI tool linked in the ParkTool website article that accompanies this video worked just fine.
In my case I am building a 16" BoB trailer wheel with a 36h Shimano Alfine Generator hub (70mm flange dia.) so the spoke length is ludicrously short. (111mm)

Author — Joe Bieniecki