steerer tube a little bit exposed above spacers - is it ok?

[moose8]

I am experimenting with some stems on my carbon bike. One of them that I want to try has a different stack height than my other stems - as a result, the spacers I have don't quite fit and there is a bit of steerer column exposed above the stem - maybe a centimeter or so. I haven't ridden it like this - is it safe to do so? It's a carbon steerer tube. I don't have the right size spacers to cover it as it is cut currently.

[bikerboy337]

No... dont ride it...

if the spacers and stem are not taller than the steer tube, you wont be able to compress the HS properly and it will be loose... esp. with a carbon steerer, you cant to this (or with any steerer)... you need to grab a spacer to ensure the stem/spacers are a few MM taller than the steer tube so you can compress the headset with the top nut...

[moose8]

Thanks - I will stick with the original stem until I can get to a bike shop.

No... dont ride it...

if the spacers and stem are not taller than the steer tube, you wont be able to compress the HS properly and it will be loose... esp. with a carbon steerer, you cant to this (or with any steerer)... you need to grab a spacer to ensure the stem/spacers are a few MM taller than the steer tube so you can compress the headset with the top nut...

[Mark McM]

I am experimenting with some stems on my carbon bike. One of them that I want to try has a different stack height than my other stems - as a result, the spacers I have don't quite fit and there is a bit of steerer column exposed above the stem - maybe a centimeter or so. I haven't ridden it like this - is it safe to do so? It's a carbon steerer tube. I don't have the right size spacers to cover it as it is cut currently.

This a two part question, and you've only asked the second part. Without additional spacers between the stem and top cap, there is no way to properly pre-load the headset. So you'll need to add spacers above the stem to adjust the headset before you tighten down the stem. (In fact, it is quite common to cut a carbon steerer slightly long so the stem clamp doesn't crush the un-finshed top edge of the cut steerer tube.) But once the headset is adjusted and the stem tightened, it's perfectly safe to remove the spacers above the stem.

[Der_Kruscher]

FWIW Most manufacturers recommend that their carbon steerer tubed forks have at least 5mm above the stem anyway to prevent crimping the carbon at the top. Easton actually recommends 1cm above the stem for their forks (or at least the EC90 SLX) which my mechanic suggested was overcautious of them but I told him to comply with their instructions to be safe.