cormacf

Since I'm new to non-quill stems, after I feel fairly dialed-in, how much space should I leave above the stem when I cut the steer tube on a road bike? I was thinking maybe 2cm or so should leave some options open without looking super-dorky or creating a safety hazard? Thanks!

aplcr0331

Just enough to mount your GoPro.



Or cut it low so only a top cap fits if you're much more cool than me.

datlas 

Cut it as low as you like, but realize if you do that you may decrease the resale value of your bike.

Iride01 

To me it looks dorky sticking up above the stem......... unless you have a use for it, but then that makes the user dor asd;lfkjas;dlkfja;lkjasdflkj;lkja;sdflkjjj as;dlkfj;lkjasd;lfkj ky if they do have a use for it.

I'm new to the no-quill look too, so my views may also change.

Does it affect resale of the bike? Only if you cut it too short and you can't properly mount any stem on that bike.

Does it affect resale of the stem? Yes, the shorter you go, the less buyers you'll have that will be will to buy it and hope it fits their bike. Not a lot will be able to measure what they have and figure what they need.

DiabloScott

At least one 3mm spacer above the stem for most carbon steerers.
Flush is OK with aluminum.
More than 5 is dorky.

pesty

Personally, the only reason I leave any steerer tube above the stem is if I plan on selling the bike in the future or anticipate having to raise the stem. On the latter, I might leave a little bit if I had to go with a more neutral stem angle (between -2º and -7º) to get a proper fit. This would be so if for some reason I HAD to raise the tops of my bars, IE: due to injury recovery, or whatever, I would have some room to do it. If I can get a proper fit with a -7º or greater stem, I'll cut the tube about 3-4mm below the cap. Else, I'll cut it about 7mm above and use 10mm of spacers.

The reason you see so many bike reviews with so many spacers above the stem is because they typically have to return those bikes and/or set them up for other reviewers. If you are pretty comfortable with your position and know it's not going to change, there's no really compelling reason in my mind to put spacers above the stem.

{edit** Some will say always go above the stem with carbon... if you have a proper expander plug, and not a star nut, I see no reason to do this. And never use a star nut in carbon.{/edit**

jitteringjr

Velominati ? The Rules
Rule 45

Psimet2001 

Enough to be able to re-sell it. as for looks - who care.

Sy Reene

It can suck if you decide to change stems down the road, and find it has a taller clamp area on the steerer tube than your prior model, and you've cut down the steerer tube..

chaadster

The "correct" is answer is to always follow manufacturer specifications, but...

As noted, for carbon steerers, generally it's good to cut them flush to the top of the stem (so that you've got full distribution of clamping forces), which means using a spacer. I agree that 3 - 5mm height for that spacers is sufficient (given most expander plug and top cap setups) and also the limit of acceptable aesthetics (IMHO).

Aluminum steerers you can comfortably cut just below the stem (3mm, to have enough compression space for bearing tightening) and get a cool, flush mount top cap.

All that said, plenty of people successfully cut carbon just below the stem, and even some manufacturers (e.g. Cannondale, I believe) spec that cut, too, so provided you torque everything to spec and use a properly long and supportive expander plug, there's probably very little to worry about even if it's not recommended by the manufacturer.

But, you didn't hear that from me...

DrIsotope

Just so long as you're not using too many spacers under the stem, put as many as you'd like above it-- provided your fork has a maximum amount of spacers that can be run. Cervelo spec'd having the top of the steerer tube 4mm below the top of the stem. So that's what I've got.

I have seen bikes out there with at least an inch of spacers above the stem, and that periscope looks absurd. Functionally fine though, I imagine.

rpenmanparker 

Thst’s not a real issue. All common stems are 40 mm tall at the clamp.

rpenmanparker 

You don’t count spacers above the stem against the total allowed.

rpenmanparker 

We don’t seriously disagree here I would just say follow the fork maker’s advice. Done and done. Tall steerers above the
stem can be risky if you go over the front of the bike.

My own opinion is that worrying about resale is stupid. It is your bike. Make it right for you.

f4rrest

You can always disguise the periscope with a hair scrunchie or two.

Sy Reene

Source? Hard info to find.. so far digging, I see that Thompson Elite stems are 36mm, Deda Elementi are 41.5mm, Ritchey Classics are 42mm, FSA are 40mm..

DrIsotope

Of this I am aware. Perhaps I was not clear enough-- so long as you do not exceed the maximum number of spacers below the stem, you can have as many as you want above the stem. But the OP mentioned 2cm, and 3/4" of spacers above the stem will look... meh. I don't run any spacers above the stem on any bike here. But I also manufacture my own stem caps, so there's that.

Hell, Cervelo says a maximum of 50mm below the stem, but the steerer us only long enough to fit 35mm. I'm guessing they make the fork with just one steerer length, so anyone with a frame smaller than a 58 gets to cut it, or raise the periscope.

Fiery

Here is a fairly good overview: Stem Review - Fairwheel Bikes Blog

It is true that 40 mm is about the average (including most Deda models actually; I've never seen a Deda with a 41.5 mm stack height), but 42 mm is far from rare. I've already corrected rpenmanparker on this in another thread, and he seemed to accept it at the time, but I guess he forgot about it later.

Regarding the OP question, I don't go through bikes frequently enough to worry about resale value. Using a 40 mm stack stem at the moment, I cut the steerer as long as possible to fit a 5 mm spacer above it. This leaves me with the option to use a 42-43 mm stack stem while still keeping a spacer above, to move the stem 5 mm up or down if I feel like it without really increasing the loads on the steerer.

Mike F

If you do cut it... get a hose clamp as a guide and a carbon rated hack saw blade - 30+ tpi.

rpenmanparker 

I use FSA. You should too.

Seriously, my apologies. Senior moment.

I just don’t care about what will happen tomorrow regarding my bike. I build it to be my idea of perfect today. If I want to change stems, I will either buy the same depth I already have, or build a new bike.

rpenmanparker 

I really like the Dremel tool for cutting stems and carbon seat posts.

f4rrest

Do you use a guide with it?

rpenmanparker 

Just a spacer held in place by a spare stem I have. Because the top of the steerer is always hidden and never contacts anything, there is no need for the top surface to be perfect. I like to think that position represents a triumph over my usual anal-retentiveness. Feels good.

Fiery

What do you do about the flying carbon dust?

pesty

try not to inhale it.