tekhna

I'm putting an Ambrosio Campy spaced cassette on a Shimano splined wheelset so obviously it's dished for Shimano--I'm guessing I'm going to have to redish the wheel but can anyone confirm that?

IthaDan 

Why would dish matter?

Dish is what centers a rim to the center between the axle's two locknuts. It's kind of an objective thing, not something that one manufacturer can do differently than another.

Cassette thickness and freehub body length are a different matter, but I can't imagine they'd be different enough between the two to force you to offset the axle (and subsequently re-dish) the wheel for frame clearance barring something like a very chunky set of chainstays that JUUUUUUST barely clear right now.

tekhna

We'll see! I know frequently when changing freehubs you need to redish, but perhaps (fingers crossed) all I'll need to do is adjust the derailer alignment.

IthaDan 

Really?

I have *never* heard of that.

E: AH! …Redishing isn't really the event here. It's changing the amount of axle protruding from the hub body to get the cassette locknut to clear the frame that subsequently necessitates the redishing that is the event.

Al1943

If the hub flanges have not changed then the "dish" will not change either. The center plane of the rim should be on the center plane of the bike frame. This is usually the mid point between the axle locknuts, chain stays, and seat stays.

davidad

To get the cassette lock nut to clear the frame you need to change the washers on the axle to space it away from the dropout and then redish the wheel.

IthaDan 

Right, but there's a middle step in this whole process (New freehub body + new axle spacing => redish wheel instead of new FH body => redish the wheel) that was a little lost in the OP.

I'd figured it out on my own, but thanks for explaining it

Let's not forget that there's a pretty high, non-zero chance that the cassette lock nut will clear just fine as it is. I know firsthand that mavic component wheels, DT hubbed bontrager wheels, zipps, reynolds and neuvations can swap from 8/9/10shimano/sram to campagnolo without a redish (at least on my steel, ti and carbon frames- I'll concede that on an old cannondale or something with giant chainstays there might be an issue). Hell, the OP isn't even swapping freehub bodies, just getting a campy spaced cassette that has shimano/sram splining.

Drew Eckhardt 

Right. Campagnolo 9 speed cassettes are wider than Shimano 9 by about 1.5mm and Campagnolo 8 by about 1mm with splines to match. Some hubs (12mm axle Powertap, Campagnolo C-record cassette hubs) take a different spacer configuration and dish change to make that work, some build the offset into the freehub (15mm power tap) so no dish change is needed.

A Campagnolo spaced Shimano splined cassette may (flat cogs) or may not (Wheels Manufacturing machined an Ultegra or Dura Ace big cog carrier to overhang the spoke side like higher level Campagnolo 10 cog cassettes, and you could use a dimpled sprocket like lower level Campagnolo 10 speed cassettes) move the lock ring.

If the lock ring moves you may or may not need extra spacers to clear it.