'''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
I assume by "31 cm" you mean 31.8 mm. OK, now is your current fork threaded or threadless?
If it's threaded I don't know of any quill stems that have a 31.8 mm handlebar clamp. However, there are threaded to threadless adapters that replace a quill stem and let you use a threadless stem. Here is one:
If it's threadless (or you use the above adapter) it's no problem. Almost all 1-1/8" threadless stems come with a shim to let them fit a 1" steerer and every LBS will have a drawer full if your particular stem didn't include one. And 1-1/8" threadless stems with 31.8 mm handlebar clamps are nearly the standard these days.
I use a shim, and have no problems. Just make sure you get a new headset compression cap that is 1-1/8" wide on the outside, but will fit into a 1" fork. I don't think any of the plastic ones do this, but a nice metal one definitely will--I think mine is made by Bontrager, but I'm sure other people make them.
I doubt KB made it in Santa Cruz , he has had his name become a Brand used by the Trek Corp.
Yea a metal Cap is a Good way to go. But it is just there to fine tune the headset pre load.
all the clamping bolts beneath it are loosened then,
after the stem is tightened around the steerer tube, there is no load on the cap .
it actually could be removed.. so really the plastic ones are fine ,, as is carbonfiber ..