I've got a WTB Laserdisc Lite hub laced to a Mavic 219 rim. I just purchased a WTB Laserdisc DH 20mm hub. I'm wondering if I can take apart my old wheel and swap hubs, of if the new hub requires different spoke lengths?

Your going to need some basic numbers about the hub and rim (ERD, hub flange dimensions, # of crosses, etc.)...

http://www.bikeschool.com/spokes/
http://www.damonrinard.com/spocalc.htm
http://www.promechanics.com/tutorial/spoke.htm
http://www.dtswiss.com/

There are a bunch of other spoke length calculators on the web. I usually run the numbers on two of these and compare.

Thanks. Those will come in handy if I have to buy a new wheel. I was wondering, though, if anybody knew if the two WTB hubs in question have the same measurements? (I haven't received the new hub yet).

Thanks. Those will come in handy if I have to buy a new wheel. I was wondering, though, if anybody knew if the two WTB hubs in question have the same measurements? (I haven't received the new hub yet).

Does the WTB site have measurements for the above mentioned hubs? It would be my first place to look, then over to Sheldon's and see if the hubs are in the spoc-calc excel sheet.

If the measurements are not the same, run it through a couple of variations and see how close they are. If it is only 1mm different you may be able to get away with it, but much more than that...

Good luck,

JmZ

I've answered my own question and I'll post the answer here in case anybody has the same question. The answer is "No, the spokes aren't interchangeable between a WTB LaserDisc Lit hub and a WTB Laserdisc DH 20mm hub because the 20 mm hub is spaced at 110mm whereas the standard QR hub is spaced at 100mm.

As far as I can tell, 110mm for a 20mm hub and 100mm for a QR hub are standard, so in all likelihood, one would never be able to relace a rim to a 20mm hub with the same spones.