View Full Version : spoke length

05-06-2009, 01:49 PM
Here we go again. Correct me if I am wrong here but I want to pass on to the wheel experts my caculations on spoke length. Keep in mind the axels and hubs are built as per instructions on the DR. I have figured in inches converted to mm and back and forth. I came up with a spoke as follows.

length = 10.402" or 264.2113 mm

Inside siameter of 21.5 "
# spokes 36
# of crosses 3 one site said use only 2 cross ???
Nut to nut 3.75" outer edges of flanges
nut to flange 0 no outer nuts here so assumed this figure
Flange height/ radius 1.13"

That is it and probably all wrong so give me some input for the next step is to purchase various sizes and try out. Hate to act like a stupid butt but who in the heck would have known it took a rocket scientist to figure this. This subject get really involved from reading on other sites. *** Thanks loads and will be watching. gphil Brad you there??:rolleyes4:

05-06-2009, 03:08 PM
If you use the calculator I posted, the ERD is 547-549mm for most 26" rims. if you use any measurement from 546-550mm for the ERD, it won't matter, you'll still get a spoke length that will work. If you made the flanges according to Brad,s plans, the hub flange diameter (Center of spoke hole to center of spoke hole on the oppoite side) will be 2 1/4", or 57.15 mm. Assuming you made the hubs 3 1/2" wide, the center of the hub to the center of the flange is slightly less than 1 3/4". (1/2 of 3 1/2"). No ned to be too critical, 1 3/4" for that measurement is very close. According to those calculations, you'd get spoke lengths of 262.4-264.4. Your measurements come to 264.2. you could use either 262mm or 264mm spokes with no problems. Check your donor bikes. You may find you already have 264mm spokes since that's a common length.

05-06-2009, 07:29 PM
I am so pleased to see that I have been in the ball park with my numbers and your note "Kid" really is great. Thanks for the comeback. You know I was examining other spokes from the bikes I have and the ones for example I took out seemed like they were very close to working. Just wanted to be as close to perfect as I could. Yes have been following the plans to a "T". Your figures and mine are almost exact. Mine a little off because of old eyes I bet. But thanks once more. I may get this thing going yet. Bet the second one will go faster. Input always welcome guys. gphil

05-06-2009, 07:56 PM
No problem. You'll find when using thes calculators that a few mm difference in the ERD and hub center to flange measurements have little effect on the length of the spokes. I used spokes from a donor for my DR wheels. Even though I made the hubs an inch and a half wider, the used spokes worked just fine. There are those who say used spokes are stronger than new, because they are already stressed and stretched out, leaving less chance of them breaking. I think it was Gil from the old forum who went with new spokes on a DW, and a few of them broke, which led to the disussion of new vs. used spokes.