Can anyone tell me if I can reuse the existing spokes if changing the rear hub from a shimano deore m525 to a superstar switch hub or would new spokes be needed ?
Thanks

Depends on hub flange size etc. I reused spokes from a hope pro2 onto deore as spoke size was same. Check dtswiss spoke calculator site. You can work out if spoke size same for both hubs, or close enough (1 or 2mm makes little difference IMO).

Spoke length changes very little as the hub flange diameter increases; I just replaced an old American Classic jobby (massive) with an XT hub (much smaller) and reused the spokes. They don’t stick quite as far into the nipple but it’s plenty far enough. Assuming your spokes aren’t right on the tolerance now I would just go for it, it’ll probably be fine!

wot phiiiiiiiil said, you’ll likely be fine.

try…

http://www.sapim.be/index.php?st=spokelength

easy eh?