spoke calculation problems - campy lo-flange to Nisi
 

Hey gang, can you give me a hand with this?

I just need to know how to calculate my spoke length for my new (NOS) Nisi tubular rims, but I can't find them or my hubs on the online tools I tried.

I currently have Ambrosio "evolution" clinchers, radial on the front and radial / 2x driveside on the rear.

I need some help to figure this out. The rims say "Moncalieri Torino Italia" ... though there is a hole through the text.

Hoping I can use my old spokes, if I could just figure out the ERD for these NISIs. Please help if you can!

Thanks!

-m

You need to take 2 spokes and thread a nipple onto them. Place them in opposite holes and measure the distance between their ends in the middle. Then measure the length each spoke from the nipple head (lower size) to the end of the spoke. Add those three numbers and you should be about on the money for ERD(there are various ways to do this you could also just insert a nipple and put a mark on it with a razor blade and then measure from below the head to the mark and multiply by 2 then measure from spoke hole to hole directly across the rim to get the ERD). Shops have papers charts for doing it by holding the rim up to it, but I have watch mechanics doing it and it is half assed and not better than if you did this measure yourself. MAKE SURE YOU DO THESE MEASUREMENTS WITH THE WASHERS IN PLACE!!! Your rims use washers instead of having eyelets. Use the DT swiss calculator to measure spoke length and get spokes about 3mm shorter than suggested all around.

Also see:
http://www.sheldonbrown.com/wheelbuild.html
dimensions for your hubs should be in this (spocalc)

I came across this site the other day, I know they list the hubs, maybe they have the rims too:

http://www.geocities.com/d_halem/wheel/wheel.html

You can only reuse the spokes if you keep them in the same positions and just change the rim. Can't unlace and reuse.

I went through this recently. Most are of the opinion that if you have low miles on your spokes there is no problem with reusing your spokes regardless of the position you put them in. You could even cut them to size if they were longer than you needed, but seeing as the front is radial you'll probably need new spokes. I recently relaced a set of wheels and kept the spokes in the same position (i.e. trailing and leading right and left side) even though I was told that shouldn't matter either. Spokes are steel. It's the hub you have to worry about. It should be laced in the same pattern, but if it was radial you can probably safely relace in a cross pattern. Just don't go from cross to radial.

Figuring out ERD is much simpler than that. Get a piece of string or twine. Tie a nice big knot in one end, and slip it through a hole from the outside of the rim. Find the hole opposite it and put the string through it. Pull the string taut, and mark it at the point where the end of the spoke would be. Remove the string from the rim, pull it taut, and measure the distance from the knot to the mark.

The stretch of a piece of string does introduce some error, but it's probably pretty small if you are careful.

thanks guys. i went from cross to radial with my front hub ... why is that an issue?