[unusualpunk]

OK I need to some info:

1. Whats the ERD is for a mavic 321

2. "Hub flange diameter", and "hub center to flange center" for a 2003 Atomic ircorp QR rear hub, and front 2003 Atomic aicorp QR hub, and shimano XT QR hub

Can you tell me how to figure it out myself, without having to buy new tools, or supplies.

 

[Phatswalla]

http://www.dtswiss.com/index.asp
Go down to Spoke Calculator

Email Atom Lab or check online on shimano's site to get hub specs. Best is to get yourself a caliper and you can measure the hubs yourself.

 

[Repack]

I'll probobly lose you on this, but will try anyway.

1. Meassure the hub width at the lockrings. Standard front is 100mm, standard rear is 135mm (both mountain).

2. Divide this number by 2.
Rear = 67.5mm
Front = 50mm.

3. Meassure from the flange to the locknut. Subtract the number from the half-width (either 67.5 or 50 depending on front or rear).
Remember that a rear hub is asymetrical, as is a front disc. Be sure to keep you numbers straight.

When you measure flange, be sure to do it at the spoke holes and not the outer edge.

A set of calipers will make this MUCH easier. You can even draw parallel lines on a piece of paper and use them as a reference.

 

[Brian HCM#1]

321 ERD is 536.5

 

[Wingnut]

Go here:

Linky poo

Click on the HB-M tab at the bottom. It has all the specs for all shimano hubs.