So its time for a new wheelset and ive decided to get spank tweet rims laced to hope pro 2 evo single speed hubs. The only problem is I cant find spokes for the right length. I checked a spoke calculator and it says for a 4 cross pattern, I need 267.1mm and 267.2mm spokes. Do the spokes have to be exactly that size? Or will I be ok with 267 mm spokes?
267 will be fine (assuming your measurements are correct), you could probably get away with 268 though they may break the plane of the nipple top ( i doubt it...).