Having knackered my old (narrower) Stans Arch, I need a new rim. I am giong to go for a ~30mm internal width to suit 2.25-2.5 tyres in the new wide fashion and am considering carbon. Now here’s the Q: it appears that folk tend to build carbon such things with <32 spokes for a more forgiving ride it appears, but my hub is 32. Does anyone have experience of different spoke counts on carbon rims? How important is this issue?

On your MTB, comfort will come from the tyre. If you want a little flex in the wheel so it feels more like an aluminium rim when cornering, use lighter spokes such as DT Revs.

I have a pair of carbon rimmed 26″ wheels with 32 spokes. They are stiff, but I don’t think that they are unforgiving.
Reducing the spoke count is probably not a good idea. Carbon rims are generally stiffer than alloy rims, so they don’t dissipate the load around the system quite as well. Bigger gaps between spokes which you will have with a lower spoke count will exacerbate this problem.

Light Bicycle say you can’t use unbutted spokes as they don;t have enough ‘give’ and they won;t warrant wheels built with them but I’ve not heard them say anything about reducing spoke count for comfort. As above, on an mtb wheel ‘give’ is a tiny part of the amount of comfort you’ll see – you want a stiff wheel to reduce deflection on corners, really.

Running Light Bicycle AM 728 with twenty eight spokes front and back on Sapim CxRay’s on DT 240 hubs. Love em

Triple butted spokes worked better for me than single butted, but less harsh, still plenty stiff

Depends on the lay up, when I was buying my LB’s I was going to go for 28 hole xc layup.

When I told them my weight, and riding style, (xc mincer) they said nah, 32 hole AM layup for you. I wasn’t going to argue with them, I’d rather the extra strength I suppose.

I have two sets of LB rims both 650b 38mm external 31.8mm internal. One set 32 bladed spokes (LB built them) the other pair 24 db spokes as I swapped the rims on an old set of Hope Pro3 XC3 wheels. I don’t notice much difference in feel. The rims are pretty stiff in the size I have, I’ve had nipple heads pop off the 32 spoke set (don’t go for alloy nipples) and a spoke break on the 24s and the wheels didn’t even go all that far out of true.

Given free choice I’d go for the most standard build possible, 32 readily available J bend spokes. Makes life so much easier when stuff breaks or you just want to replace a rim or hub.

Thanks for all the feedback. @Rubber_B – I already learned my lesson about aluminium nipples!

So it appears the only question is, do I really need carbon rims enough to justify the dosh? Hmmmm…

Question of want rather than need I think 😀

When I bought mine I think prices were a little lower, you got $1.6 to the pound and the LB rims cost me about £120 each by the time they were in my hands. These days I think they would be more like £200 each and I personally would be looking at DT or Stans Mk3 rims instead. But if you have a hankering for carbon and have the cash I guess you just have to go for it 😀