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Spoke length calculator, where did i go wrong?

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Spoke length calculator, where did i go wrong?

Old 04-26-21, 12:58 PM
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PimpMan
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Spoke length calculator, where did i go wrong?

I have used two calculators and both show 284mm spokes, however once i got them installed using 3x cross pattern, tighten them to the max i found out hub was loose, i wonder where did i go wrong with my calculations?

When i bought 281mm spokes it went in perfectly fine.


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Old 04-26-21, 02:43 PM
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Putting the same numbers into two different calculators should yield the same spoke length. Since it did, that means something's wrong with the numbers you entered. Did you arrive at them by measuring, or by specs?
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Old 04-26-21, 04:02 PM
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How did you arrive at your effective diameter number number?
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Old 04-27-21, 12:01 AM
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Originally Posted by Rolla View Post
Putting the same numbers into two different calculators should yield the same spoke length. Since it did, that means something's wrong with the numbers you entered. Did you arrive at them by measuring, or by specs?
I measured the distance, but i used tailor/clothes soft tape measure maybe that's the problem.
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Old 04-27-21, 12:49 AM
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YouTube shows how to measure for the ERD. You should check 90 degrees from the first measurement. I use Wheelsmith rim rods and get the other info from multiple sources.
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Old 04-27-21, 02:13 PM
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Checked my tape measure, was only shorter off by 1mm.

Originally Posted by Rick View Post
YouTube shows how to measure for the ERD. You should check 90 degrees from the first measurement. I use Wheelsmith rim rods and get the other info from multiple sources.
I measured ERD according to this chart.





i have another set of small rims it has 533 - 20 stamped on inside, and after checking ERD same way as i did with big rims i also get 533mm, so maybe i made error somewhere else other than ERD, i will double check again tomorrow.

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Old 04-27-21, 07:59 PM
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Old 04-28-21, 02:33 PM
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I am rebuilding tried another rim that had 291mm spokes three-corss pattern however calculator again gives me 287-298mm










EDIT: Ahh its all right i measured a spoke that was probably not original for that wheel and shorter with tape measure that was 2mm shorter than normal so i get 291mm.
In reality i just built this wheel with 191mm spokes and they are too short, so i calculator was right real size of the spokes is 297mm!

Last edited by PimpMan; 04-29-21 at 02:01 AM.
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