Yet Another Spoke Length Question
 

I've reused spokes before, but that was just swapping rims. This time, the rims (32 hole Open Pros) are basically new (no wear on the brake tracks), but I recently noticed that I have a crack on my rear hub's flange. The hub is a 16 year old King. I also happen to have an unused Ultegra 6700 hubset sitting in my bin. I am considering swapping the old hubs for the new. The diameter of the new hubs' flanges(48.5mm front, 53.9 rear) are a little smaller than the old (50mm front and 56.8mm rear according to my calipers).

I don't have a lot of $$ to put into this. Could I reuse the spokes on the new hubs? In other words, are the differences in the hub flanges close enough to reuse the old spokes (which are basically new)?

For what it's worth, it is a 32 hole 3 x pattern. Wheelsmith spokes, brass nipples, Open Pros....

Yet Another Spoke Length Question
 

You will probably be ok for the front, but the rear may be a little long.

Go to any spoke calculator program to confirm. You don't need an exact rim diameter (just something close like 605mm). Same with CTF ditance,, jut eyeball it or use something typical like 36/19 for the rear and 35mm fro the front.

You're not looking for an exact spoke length so the errors won't matter, as long as you use the same data everyplace except for flange diameter,where you'll enter the original hubs and the new hubs and note the change in calculated spoke size.

I expect that there'll be only a slight change, since the spokes (3x) are nearly tangent, and the effect of a small flange diameter will be small. But it helps to confirm which is why I'm having you run the numbers.

If there is a change, the impact depends on high in the nipples currently reach. For instance if the spoke should be 1mm shorter, but your spokes currently don't reach the tops of the nipples, you'll be fine. OTOH if the spokes are already reaching reaching the tops of the nipples, you have limited room for the spoke coming up higher on the new built.

You're good to go!

Good advice, but I might add that to ensure that the spokes won't be too long, you might do well to add a brass spoke washer under the head of each spoke as recommended by Gerd Schraner, it makes sense and guarantees a nice tight build (i.e. the spokes end up being nice and snug!) Here's a picture: http://i.ebayimg.com/t/Brass-Spoke-W...wIVZQ~~0_1.JPG HTH -
Good luck -
- Wil