Spoke calculator

Quoted message said:

I am looking for a simple spoke calculator, specifically w/ a database of hubs and rims that is
current. I am having trouble finding a database that includes mavic cxp21 650c rims. thanx, andy

There are plenty of spoke length calculators on the net, based on the formula in The Bicycle Wheel.
I use one that I made myself using a spreadsheet. It does require measurement of the effective rim
diameter, easy to do with two spokes (with nipples) in opposing holes, hub flange separation and hub
spoke circle diameter.

Measuring those yourself is more reliable than depending on published databases of unknown accuracy.

--
Ted Bennett Portland OR

Ted Bennett said:

Quoted message said:

I am looking for a simple spoke calculator, specifically w/ a database of hubs and rims that is
current. I am having trouble finding a database that includes mavic cxp21 650c rims. thanx, andy

There are plenty of spoke length calculators on the net, based on the formula in The
Bicycle Wheel.

No, all spoke length formulas, including that in the Bicycle wheel are based on the simple geometric
"length of a line in 3-space" formula. The Bicycle Wheel is a very good book, but it didn't invent
geometry. (It is possible to aquire a spoke length formula via the "folding about a line" technique
taught in Engineering design graphics, and this amounts to finding a 2-d solution and then folding
it to the third dimemsion. Of course the answers are equivalent even though the appear different.)

Damon Rinard was nice enough to do a good deal of work and Sheldon was nice enough to archive
Damon's site:

sheldonbrown.comspocalc.htmOpen ↗

Quoted message said:

I use one that I made myself using a spreadsheet. It does require measurement of the effective rim
diameter, easy to do with two spokes (with nipples) in opposing holes, hub flange separation and
hub spoke circle diameter.

Measuring those yourself is more reliable than depending on published databases of unknown
accuracy.

--
Ted Bennett Portland OR

Precious Pup said:

Ted Bennett wrote:

Quoted message said:

Quoted message said:

There are plenty of spoke length calculators on the net, based on the formula in The Bicycle
Wheel.

Quoted message said:

No, all spoke length formulas, including that in the Bicycle wheel are based on the simple
geometric "length of a line in 3-space" formula. The Bicycle Wheel is a very good book, but it
didn't invent geometry.

That's all correct. I did not mean to imply that Jobst had invented it. Likely I wrote that because
that was the first place I saw it, and I adopted it.

--
Ted Bennett Portland OR