# Bicycle Mechanics - spoke length question

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donncha
03-09-11, 12:31 PM
Rim: Mavic Open sport, (not the pro ones)

Hub: Shimano 600 fh 6400

Using this (http://lenni.info/edd/) online calculator with 36 spokes and 3 crosses I get a spoke lengths of:

Spoke length left: 293.2
Spoke length right: 291.7

I am a little concerned with the data on the site, measurements for the 6400 hub are hard to come by and there seems to be some debate about the ERD of the open sport rims.

Should I take the average of 292.45 and get 292mm spokes?

Doesn't the length of the nipples also come into play?

These lengths seem a little long, are they normal for 700c wheels?

Basically I am asking which spokes/nipples should I get?

mrrabbit
03-09-11, 02:30 PM
http://www.mrrabbit.net/wheelsbyflemingapplications.php

Scroll down and grab the spreadsheet...

=8-)

ERD = 606 aiming for nipple screwdriver flat.

=8-)

donncha
03-09-11, 03:07 PM
Thanks, but the spreadsheet doesn't seem to have the spec's for a fh6400 rear hub, it has the front one but not the rear.

An ERD of 606 in the spread sheet is the same as the one used in the other spoke calculator so I'd be pretty happy with this figure.

mrrabbit
03-09-11, 03:12 PM
Yes it does...same as fh6401...

=8-)

donncha
03-11-11, 08:39 AM
Ok, put in the 606 value in the "Rim Diameter" box and 18 for "# of spokes this side" and 3 for crossings. I selected fh6401 for column A. I am using openoffice Calc, where should I find the final spoke length?

Also are you sure the measurements are the same for the 6401 and 6400? I have seen different measurements elsewhere for these hubs, then again as both are 7-speed 126mm spacing hubs I couldn't see why they would change the design. The only difference being Uniglide/Hyperglide.

Thanks very much for your help mrrabbit.