Spoke length question ...

[pjbaz]

I did my best to get correct measurements (a few are more calculated guess than scientifically perfect) and I came up with a spoke length I feel might be a little long so I'm asking for your opinions.

I'm lacing an old Schwinn low flange hub (well, it seems low to me) to a 36h 26" single wall rim off a skip-tooth ride. I'm planning on lacing it 4X. I know without pix this is tough but ...

I used the UBI calculator and came up with 277.9 based on:

Effective Rim Diameter (ERD): 559

Hub Flange Diameter: 36
Hub Center to Flange Center: 88.75 = [ 1/2 - 10.17 and 1/2 - 9.07] then I split the difference and called it 35.
Hub Spoke Hole Diameter: 2.5
Number of Spokes in the Wheel:36
Cross Pattern: 4 cross

Does that sound close?

Thanks,
J

 

[Bicycle808]

How did you measure ERD? That number seems high, and suspiciously similar to other parameters. I"m also a little iffy on how you got your center-to-flange numbers... Maybe it's me and I'm just not understanding your description of it, but here's a site I found to be helpful for taking measurements. They got a decent calc, too....

https://leonard.io/edd/howtomeasure

Good luck!

 

[The Black Monark]

Sounds to me like 36 spokes 4x should be 10 5/8" (270mm) for your rim and hub.
ERD is not the same as bead diameter. ERD for a 559 bead diameter rim, such as the old ballooners would be ~547ish I think.

 

[c.p.odom]

That 559 is the ISO bead seat size, not the ERD.

 

[pjbaz]

Guess I should actually measure ERD instead of just grabbing numbers off the Internet LOL

FTR, the rear spokes are 269 with a larger flange hub- I actually pulled a dozen of them out without needing pliers so I know they're correct

Off to the basement I go! Thanks guys, I'll report back when I get a real measurement.

 

[pjbaz]

Once I realized I was in cm and not mm things went much smoother LOL. I came up with 523 + 24 (nipple length) for a total of 547. Making my spokes 272

I edited this because 544 vs 547 was nagging at me so I measured a few more times LOL

Maybe I'll even get this thing built eventually ...

Thanks as always!
J