Headset Spacers
#1
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Headset Spacers
I changed the stem on my bike and I guess it’s a tad shorter, as the distance between the top of the steerer tube and spacer (using one above the stem) is 1 maybe 2mm. When I snug the top cap bolt I believe the bottom of the cap is contacting the top of the steerer and it’s not preloading the headset (hopefully my explanation makes sense, I followed the Park Tool video). When I apply the front brake and push forward it feels like there is play.
So I got some 2 and 3mm spacers and replaced one 5mm with a combo of these and the steerer tube is now a good 4mm below the spacer on top of the stem (maybe 5mm?). Now when I snug the top cap bolt it feels like it’s engaging more (also took several more turns), and I can still rotate the bars easily. Now when I check for play it seems to be gone.
Sorry for the long explanation!
So, is it okay if that distance between top of spacer down to the top of the steerer tube is like 4-5mm?
I rarely touch this area of the bike so I’m not as confident. Everything is now torque to spec and it feels good.
So I got some 2 and 3mm spacers and replaced one 5mm with a combo of these and the steerer tube is now a good 4mm below the spacer on top of the stem (maybe 5mm?). Now when I snug the top cap bolt it feels like it’s engaging more (also took several more turns), and I can still rotate the bars easily. Now when I check for play it seems to be gone.
Sorry for the long explanation!
So, is it okay if that distance between top of spacer down to the top of the steerer tube is like 4-5mm?
I rarely touch this area of the bike so I’m not as confident. Everything is now torque to spec and it feels good.
Last edited by Noonievut; 02-19-22 at 07:42 PM.
#2
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From: Chapel Hill NC
Bikes: 2000 Litespeed Vortex Chorus 10, 1995 DeBernardi Cromor S/S
Yes that's fine - the 1-2 mm people cite is the minimum to ensure that the top cap isn't contacting the steerer top. 4-5mm will achieve the same thing with no downside
#3
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From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
As long as the top bolt of the stem's steerer clamp is below the top of the steerer, you are fine. My preference is to have the steerer long enough to project slightly above the top of the stem and add a spacer above the stem to give me a 3-4 mm gap below the top of that spacer. That accomplishes the gap needed to adjust the headset and assures the steerer is fully supported by the stem. This is particularly useful with a carbon steerer.
#4
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From: Rochester, NY
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
The danger is greater when the top of the steerer is below the stem's top by so much that the steerer is also below the top pinch bolt. With a metal steerer less a concern then with a carbon steerer. It was the introduction of carbon steerers that the "steerer above the stem and add a spacer to allow the preload cap to not bottom out" began to be the way. Andy
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AndrewRStewart
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#5
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As long as the top bolt of the stem's steerer clamp is below the top of the steerer, you are fine. My preference is to have the steerer long enough to project slightly above the top of the stem and add a spacer above the stem to give me a 3-4 mm gap below the top of that spacer. That accomplishes the gap needed to adjust the headset and assures the steerer is fully supported by the stem. This is particularly useful with a carbon steerer.
#6
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I think a few folks are misreading the OP. He has a spacer above the stem.
OP: as long as there is enough steer tube sticking into the spacer to keep it in place, you are fine.
OP: as long as there is enough steer tube sticking into the spacer to keep it in place, you are fine.
#7
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From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Indeed you are correct and I should have read the OP more carefully. The obvious answer to his problem is to replace the 5mm spacer with a 10mm spacer. And, yes, the resulting 5 or 6mm gap will be fine.
#8
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From: Ottawa, ON, Canada
Bikes: 1974 PX-10E steep angles, sold, 1977 Witcomb stolen, 1980 Roberts 1 speed, 1987 Cyclops 3 x 6 friction triple crank, 2010 Masi Commuter 1 speed, 2017 Ribble 525 2 x 10 with Ergos
Ironic, the extra stuff (weight) you have to add so you can use a fork with carbon steerer.
#9
Kansey

Joined: Oct 2019
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From: South LA
Bikes: Cannondales, alot
too right lol I put a Easton on my bike and unthinkable just put the stem and took it to my mechanic for housing and cables. Hours after I pick it up and saw aluminum spaces😅😅 just paid and was grateful of his consideration. I am planning on ordering carbon spacers though
#10
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As the OP I wanted to come back and close the loop on this. Short answer - I'm not a very good bike mechanic (but I try!).
When I changed stems...somewhere along the way I accidentally loosened the compression plug that sits inside the carbon steering tube. I didn't know this at the time. I didn't know what it looked like before (lesson learned - use phone for quick photo), so when the compression nut was sitting 5mm or so above the steering tube I didn't know that was wrong. So I need extra spacers to clear this additional height. Fortunately I called the bike shop, explained what I was seeing, and they set me straight (sometimes you just have to see it in person, or photos).
When I changed stems...somewhere along the way I accidentally loosened the compression plug that sits inside the carbon steering tube. I didn't know this at the time. I didn't know what it looked like before (lesson learned - use phone for quick photo), so when the compression nut was sitting 5mm or so above the steering tube I didn't know that was wrong. So I need extra spacers to clear this additional height. Fortunately I called the bike shop, explained what I was seeing, and they set me straight (sometimes you just have to see it in person, or photos).
Last edited by Noonievut; 01-21-22 at 02:29 PM.
#11
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From: Eastern PA, USA
Bikes: 2014 Trek Domane 6.9, 1999 LeMond Zurich, 1978 Schwinn Superior
Ah, this makes sense. Glad you got it fixed. As long as you can 1) preload the bearings with the cap, and 2) have the stemp clamp on tube (and not "clamp on air") you are good. The 1-2mm of clamping on air might be ok but is still suboptimal. Glad you got it fixed.
#12
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I changed the stem on my bike and I guess it’s a tad shorter, as the distance between the top of the steerer tube and spacer (using one above the stem) is 1 maybe 2mm. When I snug the top cap bolt I believe the bottom of the cap is contacting the top of the steerer and it’s not preloading the headset (hopefully my explanation makes sense, I followed the Park Tool video). When I apply the front brake and push forward it feels like there is play.
So I got some 2 and 3mm spacers and replaced one 5mm with a combo of these and the steerer tube is now a good 4mm below the spacer on top of the stem (maybe 5mm?). Now when I snug the top cap bolt it feels like it’s engaging more (also took several more turns), and I can still rotate the bars easily. Now when I check for play it seems to be gone.
Sorry for the long explanation!
So, is it okay if that distance between top of spacer down to the top of the steerer tube is like 4-5mm?
I rarely touch this area of the bike so I’m not as confident. Everything is now torque to spec and it feels good.
edit: bike is a 2021 Bombtrack Hook. Top cap is very narrow/thin.
So I got some 2 and 3mm spacers and replaced one 5mm with a combo of these and the steerer tube is now a good 4mm below the spacer on top of the stem (maybe 5mm?). Now when I snug the top cap bolt it feels like it’s engaging more (also took several more turns), and I can still rotate the bars easily. Now when I check for play it seems to be gone.
Sorry for the long explanation!
So, is it okay if that distance between top of spacer down to the top of the steerer tube is like 4-5mm?
I rarely touch this area of the bike so I’m not as confident. Everything is now torque to spec and it feels good.
edit: bike is a 2021 Bombtrack Hook. Top cap is very narrow/thin.
#13
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Joined: Sep 2009
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I think I may do this...going to call the LBS and talk to them today.
Last edited by Noonievut; 02-19-22 at 07:47 PM.




