Carbon steerer Forks is it different to put a stem on it?
#1
CERVEL-LIZED!
Thread Starter
Join Date: Dec 2006
Posts: 1,696
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Carbon steerer Forks is it different to put a stem on it?
I am concerned of cracking the carbon steerer tube of my Specialized Tarmac full carbon fork. Is there any special consideration or a different tool or a different set up to do on a carbon steerer? Cheers!
#2
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 2026 Post(s)
Likes: 0
Liked 1,095 Times
in
741 Posts
There are a couple of important considerations with a full carbon steerer:
1. NEVER use a star nut. Use a stem compressor (FSA makes a good one) or the specific type of internal fitting supplied by the manufacturer. Read the fork's instruction sheet and see your LBS for what you need.
2. Do not over tighten the stem clamp bolts. There should be a torque spec on the stem, tyypically about 8 N-m. Also tighten the bolts evenly.
3. Use a stem that wraps around the steerer and tightens with two bolts. Do not use a stem with an internal clamp. By now, most stems are now designed to be compatible with carbon steerers so this isn't a major problem.
1. NEVER use a star nut. Use a stem compressor (FSA makes a good one) or the specific type of internal fitting supplied by the manufacturer. Read the fork's instruction sheet and see your LBS for what you need.
2. Do not over tighten the stem clamp bolts. There should be a torque spec on the stem, tyypically about 8 N-m. Also tighten the bolts evenly.
3. Use a stem that wraps around the steerer and tightens with two bolts. Do not use a stem with an internal clamp. By now, most stems are now designed to be compatible with carbon steerers so this isn't a major problem.
#4
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 2026 Post(s)
Likes: 0
Liked 1,095 Times
in
741 Posts
A star nut is a directionally flanged steel nut that's inserted (read pounded) into the steerer tube of a steel or aluminum steerer fork. The flanges are angled to allow the nut to be driven into and grip the internal walls of the steerer but resist being pulled out so it anchors the stem compression bolt.
You do NOT want to pound one of these into a carbon steerer as it will damage and weaken the tube.
You do NOT want to pound one of these into a carbon steerer as it will damage and weaken the tube.
#5
Senior Member
Join Date: Feb 2005
Location: Oklahoma
Posts: 9,438
Bikes: Trek 5500, Colnago C-50
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 7 Times
in
6 Posts
Do NOT use the torque spec on the stem. Use the torque spec recommended by the fork manufacturer and if you cannot find that stop at 5 nm. Trust me on this, I broke a very expensive fork at 8 nm because I was using the spec shown on the stem. Some companies like Specialized recommend 5 nm for their carbon steer tubes.
Al
Al
Last edited by Al1943; 10-22-07 at 09:15 AM.
#6
*
Join Date: Jan 2007
Posts: 3,458
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 2 Times
in
2 Posts
Also carbon steerers [generally] have a lesser maximum number of spacers allowed. Check your specific specs but in general 1" steerer=25mm max spacers, 1 1/8" = 40mm max.