Go Back  Bike Forums > Bike Forums > Road Cycling
Reload this Page >

Headtube and spacers

Search
Notices
Road Cycling “It is by riding a bicycle that you learn the contours of a country best, since you have to sweat up the hills and coast down them. Thus you remember them as they actually are, while in a motor car only a high hill impresses you, and you have no such accurate remembrance of country you have driven through as you gain by riding a bicycle.” -- Ernest Hemingway

Headtube and spacers

Thread Tools
 
Search this Thread
 
Old 03-12-10 | 09:21 AM
  #1  
ac29593's Avatar
Thread Starter
Senior Member
 
Joined: Jun 2005
Posts: 365
Likes: 15
Headtube and spacers

When I bought my bike, the headtube was cut very short by the LBS.

Right now the stem is almost flush with the top, maybe about 2.5MM higher than the top of the headtube.

I know that if the top of the stem is higher than the top of the headtube it can be dangerous to ride since the stem might not be secured properly.

How much room would be safe?

If my handlebars were just 5MM higher it would feel perfect for me, but I have been weary of putting a 5MM spacer on since I am not sure if it would be safe since the stem would be higher than the headtube.

Thanks
ac29593 is offline  
Reply
Old 03-12-10 | 09:31 AM
  #2  
TMB's Avatar
TMB
Permanent Refugee .......
 
Joined: Dec 2005
Posts: 1,256
Likes: 0
From: Okanagan Valley, BC.

Bikes: Steel

The monkeys at your LBS are idiots.

Why would they cut a steer tube that short before the bike was fit to a purchaser.

The stem should sit clear of the top of the steer tube by between 2.5 and 3 mm - the extra clearance is what gives the top cap the ability to press down on the stem assembly and tension the bearings.

Anything more than 2.5 to 3 mm is too much.

Your LBS is staffed by nitwits - chances are they ruined a fork for nothing more than giving the bike the "racer boy " look.

You could always flip the stem to a riser position, or try an different stem.
TMB is offline  
Reply
Old 03-12-10 | 09:33 AM
  #3  
AngryScientist's Avatar
Lost
Titanium Club Membership
15 Anniversary
 
Joined: Jun 2008
Posts: 4,627
Likes: 164
From: nutley, nj
get a riser stem. agree that your bike shop shouldnt cut anything before fitting you.
AngryScientist is offline  
Reply
Old 03-12-10 | 09:45 AM
  #4  
Big_Red's Avatar
Senior Member
 
Joined: Dec 2009
Posts: 160
Likes: 0
From: Aurora, CO USA
TMB and AngryScientist are right. The 2.5mm you mentioned allows for the headset preload. I wouldn't space the stem up any higher. You should be able to find a stem that gives you the rise you need. You might want to discuss this with your shop and see if they will help due to the short steerer length. Just curious, but are there any spacers below the stem now?
Big_Red is offline  
Reply
Old 03-12-10 | 10:07 AM
  #5  
merlinextraligh's Avatar
pan y agua
20 Anniversary
 
Joined: Aug 2005
Posts: 31,812
Likes: 1,234
From: Jacksonville

Bikes: Willier Zero 7; Merlin Extralight; Calfee Dragonfly tandem, Calfee Adventure tandem; Cervelo P2; Motebecane Ti Fly 29er; Motebecanne Phantom Cross; Schwinn Paramount Track bike

Originally Posted by ac29593
If my handlebars were just 5MM higher it would feel perfect for me, but I have been weary of putting a 5MM spacer on since I am not sure if it would be safe since the stem would be higher than the headtube.

Thanks
If you just need 5mm more rise, that should be easy to accomplish with a stem with a different angle.

Also is the stem angled up or down, and are there any spacers under the stem now?

If its angled down, you can angle it up, i.e. flip it. Depending on the angle of the stem that will likley raise it more than 5mm. Hence, the questions of spacers below. Moving spacers above, and flipping it might well give you the small change you want.

Otherwise buy a different stem.

__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
merlinextraligh is offline  
Reply
Old 03-12-10 | 11:07 AM
  #6  
ac29593's Avatar
Thread Starter
Senior Member
 
Joined: Jun 2005
Posts: 365
Likes: 15
There are two 5mm spacers below the stem now, and I have a 100mm with 5 degree rise angled up.

I do have another stem, which is about the same 100mm, but with a 7 degree rise.

That might do it.
ac29593 is offline  
Reply
Old 03-12-10 | 12:49 PM
  #7  
idcruiserman's Avatar
Mmmmm potatoes
 
Joined: Sep 2006
Posts: 1,921
Likes: 0
From: Idaho
I don't see the problem. It's not very often I see a bike in a LBS with a lot of spacers below the stem.
idcruiserman is offline  
Reply
Old 03-12-10 | 02:35 PM
  #8  
Big_Red's Avatar
Senior Member
 
Joined: Dec 2009
Posts: 160
Likes: 0
From: Aurora, CO USA
Maybe to determine the cause of the shorter steerer length from the shop we should ask what type of bike is this. If it is a full blown $6000 racer, perhaps a shorter height would be considered OK, perhaps the OP told the shop he was interested in a pro fit. We don't know this, but all that aside, just get a new stem and go out and ride.
Big_Red is offline  
Reply
Old 03-12-10 | 02:55 PM
  #9  
Senior Member
20 Anniversary
 
Joined: Jun 2002
Posts: 3,924
Likes: 589
From: San Jose, CA

Bikes: Too many bikes, too little time to ride

also depends on where the stem clamps are in relation to the steerer. imo as long as the top stem clamp bolt isn't too close to the top of the steerer, should be okay. i've mtb'ed with more than 5mm of stem above the steerer, just sayin'.
tFUnK is offline  
Reply
Old 03-12-10 | 07:05 PM
  #10  
ac29593's Avatar
Thread Starter
Senior Member
 
Joined: Jun 2005
Posts: 365
Likes: 15
Well, I rode a bit on my trainer today and problem solved. The minimal difference I was looking for had to do with my saddle position.

I recently bought a trainer and was messing around with my fit a bit, and did not notice I adjusted the saddle position a bit more than I should have.

It felt like a reach issue, but Im all set now.

Thanks for the replys.
ac29593 is offline  
Reply
Old 03-12-10 | 07:50 PM
  #11  
RacerOne's Avatar
Hills hurt.. Couches kill
 
Joined: Jun 2008
Posts: 3,370
Likes: 3
From: Brazil, IN

Bikes: 1991 Specialized Sirrus Triple, 2010 Trek Madone 6.5 Project One, 2012 Cannondale Caad10, 2013 Trek Crockett

Problems solved in less than ten hours or the next one's free.
RacerOne is offline  
Reply
Old 03-12-10 | 09:10 PM
  #12  
ac29593's Avatar
Thread Starter
Senior Member
 
Joined: Jun 2005
Posts: 365
Likes: 15
Yep! Good thing I only worked an 8 hour day today.
ac29593 is offline  
Reply
Old 03-14-10 | 10:27 AM
  #13  
ac29593's Avatar
Thread Starter
Senior Member
 
Joined: Jun 2005
Posts: 365
Likes: 15
I took a picture of the stem with the extra spacer below, just to see what people thought since it is always better with a picture.

Would this have been a problem if I decided to leave it like this?

The top of the steering tube is flush with the bottom of the top screw. It seemed like it held fine, but I am not sure how things will handle over time and with real road conditions and speed.
Attached Images
File Type: jpg
stem height.jpg (55.5 KB, 28 views)
ac29593 is offline  
Reply
Old 03-14-10 | 10:35 AM
  #14  
rdl456's Avatar
Senior Member
 
Joined: Jan 2010
Posts: 114
Likes: 0
From: Corpus Christi TX

Bikes: Ridley Boreas

Maybe you can measure the depth? Should have only been cut to 2 or 3 mm below the top of the stem to allow for the top cap to tighten down. Looks a bit short but I don't see it coming off if you've torqued it properly. Of course if you wanted to go 5mm higher like in your earlier post you'd be screwed. A new fork would be in your future.

Last edited by rdl456; 03-14-10 at 10:46 AM.
rdl456 is offline  
Reply
Old 03-14-10 | 10:41 AM
  #15  
ac29593's Avatar
Thread Starter
Senior Member
 
Joined: Jun 2005
Posts: 365
Likes: 15
The top cap tightens down perfectly. My fear is that the top of the steering tube is below the top screw (flush with the bottom of it), and I want to make sure it is clamped securely. If the cap is tightened properly would this be the most important, and not worry too much about the top screw clamp?

This picture is with going 5mm higher.

Last edited by ac29593; 03-14-10 at 11:05 AM.
ac29593 is offline  
Reply
Old 03-14-10 | 01:24 PM
  #16  
lukewall's Avatar
Senior Member
 
Joined: Aug 2007
Posts: 448
Likes: 0
From: NYC

Bikes: 2000 Raleigh M50. 2006 Raleigh Rush Hour. 2008 Cannondale Synapse 6.

My minimum would be 2mm below the stem. But my personal preference is to have a 2mm spacer above the stem for carbon steerers.
lukewall is offline  
Reply
Old 03-14-10 | 04:13 PM
  #17  
cab horn
20 Anniversary
 
Joined: Jun 2004
Posts: 28,353
Likes: 31
From: Toronto

Bikes: 1987 Bianchi Campione

Originally Posted by ac29593
I took a picture of the stem with the extra spacer below, just to see what people thought since it is always better with a picture.

Would this have been a problem if I decided to leave it like this?

The top of the steering tube is flush with the bottom of the top screw. It seemed like it held fine, but I am not sure how things will handle over time and with real road conditions and speed.
That steerer is too ****ing short, end of ****ing story. That is bull**** to the max, if you want marginal safe, the top of the steerer is above the TOP of the screw, not the bottom.

And your LBS cut the steertube, not the headtube.
operator is offline  
Reply
Old 03-14-10 | 04:14 PM
  #18  
cab horn
20 Anniversary
 
Joined: Jun 2004
Posts: 28,353
Likes: 31
From: Toronto

Bikes: 1987 Bianchi Campione

Originally Posted by lukewall
My minimum would be 2mm below the stem. But my personal preference is to have a 2mm spacer above the stem for carbon steerers.
+1

Carbon steerers should have the full face of the stem clamped onto the steerer. Spacer above, always. Alloy you'd get away with top screw below the top of steerer.
operator is offline  
Reply
Old 03-14-10 | 04:18 PM
  #19  
ac29593's Avatar
Thread Starter
Senior Member
 
Joined: Jun 2005
Posts: 365
Likes: 15
Originally Posted by operator
That steerer is too ****ing short, end of ****ing story. That is bull**** to the max, if you want marginal safe, the top of the steerer is above the TOP of the screw, not the bottom.

lol yeah, I was thinking the same thing.
ac29593 is offline  
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Shinkers
Bicycle Mechanics
5
09-10-17 08:52 PM
fueledbymetal
General Cycling Discussion
23
03-03-17 10:53 AM
relnix
Road Cycling
26
11-17-13 05:06 PM
rhtabor
Bicycle Mechanics
4
12-10-12 11:08 PM
kirke
Classic & Vintage
8
12-20-09 06:32 AM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.