Just installed a new headset that has a slightly different stack height on it.

Best I can get with my collection of spacers puts the top of the stem exactly flush with the top of the steerer and below the lip of the compression plug.

This should be okay right? Since the bolt sits a couple millemeters from the top of the steerer.

Only other option I have would drop the stem another 🕔 which would mean I'm not clamping on the compression plug with both bolts.

Thanks.

there needs to be enough clearance for the cap to seat into the stem... "flush" won't be correct, and the head set will act loose if the stem slips... CF is slippery.

find a 2mm or greater spacer, or reorganize to allow the clearance i mentioned.

You need the stem to be 3 mm above the steering tube , so find spacers that will do that , a 5mm spacer should help in doing so . Put it (the spacer(s) above or below the stem .

Carbon Fiber Steerers need to fully contact the stem, so a spacer above is fine and safer than the stem not fully contacting the fork steerer..

Okay, I should have been clearer. I will use a spacer over the stem, and I know that there needs to be a 2-3mm space between the top of the spacer and the steerer so the top cap doesn't bottom out.


My concern is where the stem clamps on the steerer, regardless of the spacer being over it. In the picture above, the steerer is flush with the top of the stem, and the expander plug sits above the stem. I'm assuming that's okay, but thought I'd ask.


I ended up lowering the stem a bit anyway so this ended up being a moot point.


I have however, run into a different kind of problem. I've noticed that with the stock stem, the lower bolt closes tighter than the upper. I don't remember if it looked like this before or not, but I did flip the stem after unboxing the bike.


I got a different (better) stem and put that on. It's not as bad, but there is still a difference between the upper and lower gap. I'm wondering if this could be a discrepancy in the steerer diameter?

The headline is wrong.

If you changed to a headset with lower stack, the concern would be that the stem would now be too low, and the stem cap would beach out on the steerer, making it impossible to adjust the headset.

If you succeeded in adjusting all the play out of the headset, you're good to go. Otherwise, add spacer of 2mm or so.