Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 05-11-11, 03:57 PM   #1
I_like_cereal
Fail Boat crewman
Thread Starter
 
Join Date: Feb 2011
Location: PDX
Bikes: Reynolds 853 Jamis Quest 1990s
Posts: 675
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Carbon fiber torque specs

I am considering a carbon frame (Calfee) to replace my steel frame (853 Reynolds Jamis).

I understand that torque specs on bolts must be adhered to, but where can I find those?

I have checked individual sites and have not been able to find them.
I_like_cereal is offline   Reply With Quote
Old 05-11-11, 05:38 PM   #2
Burton
Certified Bike Brat
 
Burton's Avatar
 
Join Date: Jan 2011
Location: Montreal, Quebec
Bikes:
Posts: 4,251
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
So what bolts are we talking about exactly? Your headset seats, bottom bracket inserts, seatpost collar mount and rear dropouts should all be metal and the items installed there will all have their own torque load specifications.
Burton is offline   Reply With Quote
Old 05-11-11, 05:57 PM   #3
I_like_cereal
Fail Boat crewman
Thread Starter
 
Join Date: Feb 2011
Location: PDX
Bikes: Reynolds 853 Jamis Quest 1990s
Posts: 675
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Burton View Post
So what bolts are we talking about exactly? Your headset seats, bottom bracket inserts, seatpost collar mount and rear dropouts should all be metal and the items installed there will all have their own torque load specifications.
All please. I have one torque wrench that starts at 10Nm. I am sure I will need a smaller wrench for the smaller bolts.
I_like_cereal is offline   Reply With Quote
Old 05-11-11, 07:31 PM   #4
operator
cab horn
 
Join Date: Jun 2004
Location: Toronto
Bikes: 1987 Bianchi Campione
Posts: 28,306
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by I_like_cereal View Post
All please. I have one torque wrench that starts at 10Nm. I am sure I will need a smaller wrench for the smaller bolts.
Yes you will.

In fact, for most 1 1/8 carbon steerers and 31.8 stems it'll be 5nm for stem faceplate bolts and 5nm for steerer bolts. Seatpost collar is generally 5nm+ as well. You will also need carbon compound to install post and optional for stem.
operator is offline   Reply With Quote
Old 05-11-11, 08:07 PM   #5
Burton
Certified Bike Brat
 
Burton's Avatar
 
Join Date: Jan 2011
Location: Montreal, Quebec
Bikes:
Posts: 4,251
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by I_like_cereal View Post
All please. I have one torque wrench that starts at 10Nm. I am sure I will need a smaller wrench for the smaller bolts.
OK so now that its clear we`re talking about components other than the frame - torque values will vary slightly from manufacturer to manufacturer but in most cases they`ll be neatly etched or stensiled on the component so it`ll be easy to reference.

The tech documents for anything you`re interested in should also be available from the component manufacturer.
Burton is offline   Reply With Quote
Old 05-12-11, 01:05 PM   #6
Al1943
Senior Member
 
Join Date: Feb 2005
Location: Oklahoma
Bikes: Trek 5500, Colnago C-50
Posts: 9,433
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I broke the cf steer tube on an $850 fork because I used the torque spec shown on the stem, too much for the steer tube. I'd say that 5 nm is the upper limit for cf.
Al1943 is offline   Reply With Quote
Old 05-12-11, 02:01 PM   #7
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 20,436
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 656 Post(s)
Mr Calfee will be the expert in this regard..

Seems Carbon Fiber stuff in amateur hands
is a problem waiting to happen..

but thats from reading this list..

NB , Torque wrenches are needing recalibration, occasionally .

I think Snap On, as a source for professional mechanics does an exchange
for freshly checked ones, for the Motor trade..

Last edited by fietsbob; 05-12-11 at 02:08 PM.
fietsbob is offline   Reply With Quote
Old 05-12-11, 02:20 PM   #8
DMF 
Elitist Troglodyte
 
DMF's Avatar
 
Join Date: Jun 2006
Location: Dallas
Bikes: 03 Raleigh Professional (steel)
Posts: 6,924
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by fietsbob View Post
NB , Torque wrenches are needing recalibration, occasionally.
Why? if the spec tolerances are 25% (as nearly all are on bikes)? This is not worth worrying about, IMO.

Personally, I've never seen one wander as much as 1%.
__________________
Stupidity got us into this mess - why can't it get us out?

- Will Rogers
DMF is offline   Reply With Quote
Old 05-15-11, 06:53 AM   #9
Burton
Certified Bike Brat
 
Burton's Avatar
 
Join Date: Jan 2011
Location: Montreal, Quebec
Bikes:
Posts: 4,251
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Now that I think about it - the Park Tool Big Blue Book of Bicycle Repair (the one advertised on this site that many members here seem to avoid buying) has several appendix in the back of the book. Appendix C covers most common torque values and seperates components by area, as well as detailing torque values by specific manufacturer and item model. Its not absolutely complete - but would be a good start. The same info is probably available on the PT website.

As well as a torque wrench - good reading skills help. Torque values can be specified as MAX / MIN / or BETWEEN. It always helps to follow instructions.
Burton is offline   Reply With Quote
Old 05-15-11, 09:08 AM   #10
pennstater
Senior Member
 
Join Date: Mar 2007
Bikes:
Posts: 160
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I've found this to be a handy tool:

http://www.ritcheylogic.com/dyn_prod...52-100&k=97993
pennstater is offline   Reply With Quote
Old 05-19-11, 10:25 AM   #11
RMMJ
Senior Member
 
Join Date: Jul 2010
Bikes:
Posts: 142
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by operator View Post
Yes you will.

In fact, for most 1 1/8 carbon steerers and 31.8 stems it'll be 5nm for stem faceplate bolts and 5nm for steerer bolts. Seatpost collar is generally 5nm+ as well. You will also need carbon compound to install post and optional for stem.
What is carbon compound, and what does it do? Do you need to re-apply it when you adjust your seat height?
RMMJ is offline   Reply With Quote
Old 05-19-11, 11:34 AM   #12
I_like_cereal
Fail Boat crewman
Thread Starter
 
Join Date: Feb 2011
Location: PDX
Bikes: Reynolds 853 Jamis Quest 1990s
Posts: 675
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Carbon compound is a grease that allows the carbon parts to "stick" to each other lest they slide.
I_like_cereal is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -6. The time now is 05:56 AM.