Weight Weenies
* FAQ    * Search    * Trending Topics
* Login   * Register
HOME Listings Blog NEW Galleries NEW FAQ Contact About
It is currently Mon Aug 29, 2016 7:14 pm
Recently the board software has been updated and there are some known bugs/failures:
- Avatars are currently not being displayed ✔ FIXED
- Tapatalk connection is currently broken ✔ FIXED
- Avatars cannot be uploaded ✔ FIXED

Please note that we will soon do some changes in WW board template design in case to get a fully mobile/desktop responsiveness board!
If you find more errors please post it here: http://weightweenies.starbike.com/forum/viewtopic.php?f=7&t=139062

All times are UTC+01:00

Post new topic  Reply to topic  [ 8 posts ] 
Author Message
 Post subject: Where to cut steerer?
PostPosted: Tue Jul 02, 2013 8:30 pm 

Joined: Wed Dec 07, 2011 1:26 am
Posts: 414
Location: California's country side
I have 2.5 cm sticking on top of the stem and want to do the cut now.
I am not sure if I should cut it lower then the stem top, or just about flush and use 5mm spacer above.

The steerer expander plug does have a small lip on top, which needs to be accounted for? (1mm?) So the actual steerer would need to be cut even lower. I want to keep using that expander because it reinforces really well.

Manufacturer BMC seems to recommend 5mm spacer above, I have seen almost none in the peleton have that :D
the stem is sitting directly on the headset..

PostPosted: Wed Jul 03, 2013 3:56 am 

Joined: Sat Dec 13, 2003 2:25 am
Posts: 4743
Location: Canada
That depends upon what expander and topcap set-up you are using. Generally speaking, you need to allow for enough room for the expander and top cap under the stem, which is generally a couple or three millimeters, no more.

When you cut the steerer, make sure you use a wrap of electrical tape to prevent the fibers from fraying. Use the finest saw you can find and cut only halfway through, finishing the cut on thhe other side. Clean-up your cut by gently beveling the outside edge with a fine file.

PostPosted: Wed Jul 03, 2013 4:06 am 

Joined: Thu Oct 13, 2011 5:25 pm
Posts: 169
Cutting the steerer above the stem does a better job of distributing the clamping load of the stem upon the steertube. If you don't believe me, take a look at bikes that have both types of cut executed. Those with shorter steertubes tend to have more pinching at the top bolt of the stem versus the bottom. I imagine stiffness is likely increased by having a spacer above.

Would recommend a spacer above. If you can't stand the aesthetic of that, you can always chop it further.

PostPosted: Wed Jul 03, 2013 8:44 am 

Joined: Fri Dec 24, 2010 9:37 pm
Posts: 911
Location: it's raining, it must be uk
i cut mine level with the top of the stem, stem-steerer is safety critical, i'd rather play safe

even with the lip on the plug, a 3mm spacer is plenty to allow the underside of the top cap to clear the end of the plug

if you use a top cap with a flat underside (or do some creative work on the cap with a dremel) you may be able to get away with no spacer, once you've clamped the stem the top cap is just a decorative dust cover

PostPosted: Wed Jul 03, 2013 9:17 am 
User avatar

Joined: Fri Apr 12, 2013 1:19 pm
Posts: 768
Location: South West England
Agreed with above. Level with the top of the stem, with a 5mm spacer on top.

Campagnolo; because I ride a bicycle, not a fishing rod.
M∆SON Definition / Camapgnolo endurance & bikepacking build - ~8.4kg

PostPosted: Wed Jul 03, 2013 1:44 pm 
User avatar

Joined: Fri Sep 17, 2010 4:48 pm
Posts: 214
Our team bikes come from Colnago (Colnago America is located in Chicago where we are) and when picking up our bikes we were told under no circumstances should the steerer be cut level with the stem as this causes too much stress on the steerer. We were told to leave between 3-5mm (enough for one spacer) above the stem. Surely there are multiple opinions but I'll trust my bike manufacturer.


PostPosted: Wed Jul 03, 2013 3:43 pm 

Joined: Fri Mar 24, 2006 1:26 pm
Posts: 2529
Cutting a steering tube flush with the top of the stem makes no sense. Either leave a little protruding above the stem, so it properly locates the spacer on top, or cut it slightly below the stem and use no spacer.

While cutting the steerer 2-3mm above the stem and using a spacer is wise for the mechanically inept, it's not necessary for anyone with a little skill. Tighten the top bolt with less tension than the lower and there should never be a problem. I've never cut a steerer above the stem and never had any problem.

Last edited by DaveS on Wed Jul 03, 2013 5:25 pm, edited 1 time in total.

PostPosted: Wed Jul 03, 2013 3:48 pm 
User avatar

Joined: Mon Jan 23, 2006 6:35 am
Posts: 5072
Location: New York
I agree with DaveS here a 1/16" or 1/8" below the top of the stem is fine if you want to have the top cap flush with the top of the stem. The bolt that clamps the stem to the steer tube is well below the top of the steer tube at that point.

I never took drugs to improve my performance at any time. I will be willing to stick my finger into a polygraph test if anyone with big media pull wants to take issue. If you buy a signed poster now it will not be tarnished later. --Graeme Obree

Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 8 posts ] 

   Similar Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. Bar/stem combo for 1.25" steerer?

in Road




Sun Aug 07, 2016 7:17 am

A2ON View the latest post

There are no new unread posts for this topic. Broken steerer tube - result of a crash or not?

in Road




Mon Sep 07, 2015 9:23 am

mrgray View the latest post

There are no new unread posts for this topic. MCFK Steerer for Lefty on New Cannondale Slate

in Road




Sat Dec 12, 2015 2:49 pm

morrisond View the latest post

There are no new unread posts for this topic. light fork 1" steerer and clearance for 30mm tires

in Road




Mon Jun 13, 2016 4:23 am

lanternrouge View the latest post

There are no new unread posts for this topic. 1 1/4" Steerer Where an 1 1/8" One Should Go

in Road




Tue Apr 19, 2016 4:09 am

Valbrona View the latest post

All times are UTC+01:00

Who is online

Users browsing this forum: 4ibanez, AJS914, Baidu [Spider], Bing [Bot], campbellrae, Hawkwood, jch3n, jeffy, jpanspac, KarlC, lovemyway, MSNbot Media, Nejmann, nherment, PhilippCX, Sacke, Stefano, TomColnago, whyamihere, Yahoo [Bot] and 23 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Limited