I’m building up a new set of road/cross wheels but I’m going with disc hubs for future proofing. I’ve built a few wheels in the past but I’ve either bought the parts as a bundle or just replaced hubs/rims on existing wheels.

I’ve gone for Open pro’s on Novatec D811SB/D812SB hubs but looking at the hub specs listed (pcd & flange to flange measurement) can’t see how I could possibly work out the spoke length required. I can obviously wait until they arrive and measure them but I’d like to get the spokes ordered. Can anyone help?

James

http://spokes-calculator.dtswiss.com/Welcome.aspx?language=en

You need the ERD for the rim, the PCD & distance from hub centre to flange for each side, & the spoke hole dia. Then decide on the lacing, I’d go with 3 cross & pump all that into the Wheelsmith, DTSwiss & Spokecalc programs.

Mavic usually list some stupid ERTD dia, that was thought up by Nostradamus or someone from the olden days, & has no bearing at all in Spoke length calcs.

I think Open Pro is already in the list of known ERD’s on Spokecalc. In fact, I think you can download Spokecalc as a big spreadsheet.

Another good spoke calculator is http://leonard.io/edd/

I use both the DT Swiss and above link and compare results to make sure. If your rim or hub is in their database, always check their measurements against the real world item you have in your hand.

I use http://www.prowheelbuilder.com/spokelengthcalculator/ which I’ve found to be accurate

Freespoke is my favourite, it has offsets for fat rims too 😀