Hi!

I know this is a rather silly question but the case is that I have bought a second-hand bicycle and need to know the exact lenghts for a spoke in front wheel and in rear wheel, as I am planning to buy some spares. I also need to find out the nipple lenght.

The case is that the wheels are really well-built and the hubs I have are Shimano dynamo hub (front) and Rohloff (rear), so in this case there are only 2 different spoke lenghts.

So Is there a reliable way to find out these information?