Don’t ask how, but I didn’t realise the steerer on my roadie forks was carbon until I started to cut it down. I’d measured the cut so that the stem will sit on the top of a couple of spacers, with the stem cap directly on top that.

Now, I measured the steerer so it would be a few mm below the top of the stem clamp, which, on a steel steerer, would be perfect. However, am I right in thinking that a carbon steerer needs to go all the way through the stem clamp, with a spacer on top?

If so, I’ve cut it too short 🙁

Yup, I was always taught to leave a spacer on top. Can’t remember why now, but I still do it.

Can you get a lower stacking headset or shorter stack stem?

Flip the stem (if it’s a neg rise), or get one with some rise?

However, am I right in thinking that a carbon steerer needs to go all the way through the stem clamp, with a spacer on top?

Different manufacturers say different things. It wouldn’t bother me to run it like that.

this can be fixed if you really are concerned, Bond a steerer plug in that’s the cure all cervelo do one and will stop your steerer splitting and ruining your face

Also make sure that you use a torque wrench to tighten the stem – there is a greater risk of crushing and collapsing the steerer when it is flush (part of the reason for the Cervelo problems)

Cheers chaps.