Picked up a TT bike s/h – some genius has seen fit to hack the steerer down as follows:

What do you reckon? Ride that all day mate, or no way, not safe? Stem is ca. 5mm proud.

All it’s going to do is 5 miles down the road, round a roundabout and back. OTOH, there’s more leverage on the bars, and thus the stem, of a TT bike than any other.

The piece underneath it is the sloping spacer that presses down on the headset assembly – it’s probably 10mm, could prob get a thinner one?

Id ride it as is

but i wouldnt condone it for others.

id look at getting a small offcut of steerer to put in that stem and a small spacer to put on top to stop the top ofmsteerer getting crushed and especially as thats a carbon stem.

Truth be told, if damaged its already done.

hes obviously did his city and guilds in the days pre carbon steerers 🙂

I would reduce the stack height by changing for a lower top cover like you suggested. Probably 5mm to be found there.

You can get a thinner headset cover than that.

Looks ok to me, I’d happily ride that. If you’re not confident, buy a lower stack headset cover and switch it out.

wouldn’t worry me at all.

Id ride it. In fact, all of my bikes are like that.

And im a fat biffer.

Some space is needed for the top cap, it’s totally normal.

Some manufacturers recommend a spacer above the stem on a carbon steerer, to avoid damage caused when tightening the stem bolts.

I’d head over to Slamthatstem.com & buy one of their bearing covers, will give you a good bit more steerer effectively.

If that was a single bolt clamp stem it’d be perfectly normal. The design of the stem makes it look dodgy. I’d ride on but for piece of mind change the stem/headset cover

Yes. Normal is around 1 – 3mm (depends on the stem manufacturer)

Providing the top of the steerer and stem aren’t damaged then it’s easily fixed as already suggested

Carbon stem on carbon steerer, I’d not be happy with that. As it’s a two clamp stem, it looks like the top bolt actually comes above the top of the steerer. The stem is then trying to form itself around the gap, not remaining parallel sided.

At the very least, I’d want steerer above the top bolt but if it were mine, it would have a small spacer on top of the stem to allow compression.

Thks all, good advice.

Problem with buying second hand TT stuff, you never know if it’s been owned by a triathlete…

“Some manufacturers recommend a spacer above the stem on a carbon steerer, to avoid damage caused when tightening the stem bolts.”

its pretty much industry standard for a carbon steerer

while the gap shown is normal for an alloy steerer its not how it should be for a carbon.

hence my comment about the guy who built it must have trained in the old school pre carbon 😀

but as i said first time round , id ride it – but thats my teeth.

The more worrying thing for me is that stem , i recommend to change it for something a bit more solid. Those ritchey stems were well known to come/tear apart under rotational loading (like sprinting to the line) – reminded by a friend mines doing just that on his hack bike this week.

Pretty sure my bike has an expanding metal bung flush to the top of the steerer, from memory it had a lip so effectively extends the steerer slightly.  The stem then clamps down on the steerer and the bung prevents damage to the top.

I’m guessing you would never put a star nut down a carbon steerer as it would score it.

The OP could also change the stem for a lower stack height.

The worry is that previous owner has put a star-fangled nut in a carbon steerer which isn’t really recommended by most. Shorter headset top cover would also give you an extra 5mm plus you could put an expander bung in the steerer which is what should have been fitted in the first place.

There is a star fangled nut there ?

I really hope not. That really does put a different slant in things if there is.

No worries with SFNs, it has the expander bung which seems in good order. Just the steerer a bit on the short side, but a new top cover will sort it as suggested.