HOT: Active* forum members generally gain 5% discount at starbike.com store!
Weight Weenies
* FAQ    * Search    * Trending Topics
* Login   * Register
HOME Listings Articles FAQ Contact About




Post new topic Reply to topic  [ 15 posts ] 
Author Message
PostPosted: Wed Jun 13, 2012 5:22 am 
Offline

Joined: Sat Mar 31, 2012 5:02 am
Posts: 11
Does anyone know how much weight can be saved by cutting the seat post? I'm interested in g/mm or g/cm. This could easily be determined by knowing the difference in weight between a 27.2 x 280 vs a 27.2 350 3t dorico team seatpost. Unfortunately, I can't seem to get weights online anywhere including the 3T website and weight weenies and I'm trying to determine if the risk of not being able to raise my saddle higher is worth the return. Thanks.

_________________
2011 Cervélo RS - SRAM Red


Top
 Profile  
 
PostPosted: Wed Jun 13, 2012 7:17 am 
Offline
User avatar

Joined: Wed Oct 31, 2007 10:32 pm
Posts: 7410
Location: Los Angeles / Glendale, California
Take your seatpost apart.
Weigh the carbon shaft.
Measure the carbon shaft.

Measure the distance you plan on cutting off.
Calculate potential weight savings.

Decide.

:|

_________________
Exp001 || TeamLACBC


Top
 Profile  
 
Posted: Wed Jun 13, 2012 7:17 am 


Top
  
 
PostPosted: Wed Jun 13, 2012 7:50 am 
Offline

Joined: Fri Oct 29, 2010 11:35 am
Posts: 51
No point in carrying the extra weight... Chop it!!! :beerchug:

Then tell WW how much you saved!!

_________________
Follow me on twitter:- MrAliBongo


Top
 Profile  
 
PostPosted: Wed Jun 13, 2012 10:35 am 
Offline

Joined: Fri Mar 23, 2012 8:56 am
Posts: 25
Location: lancashire UK
I cut 4" of a carbon seat post ( I cant remember the make ) but it weighed 35g

Barrie


Top
 Profile  
 
PostPosted: Wed Jun 13, 2012 1:33 pm 
Offline

Joined: Sun Jul 10, 2011 9:03 am
Posts: 292
Cut it off. Weigh it. Then you'll know how much you saved :wink:

_________________
r o y g b i v


Top
 Profile  
 
PostPosted: Wed Jun 13, 2012 1:47 pm 
Offline

Joined: Wed Jun 10, 2009 2:16 pm
Posts: 353
Location: Austin, Texas
the only way to know for sure is to cut it and weigh it after. Grams/cm may vary along the length - my Syntace P6 post had a thinner wall at the very bottom end compared to the rest of the post.

I saved 39 grams by cutting around 9 cm from my post.


Top
 Profile  
 
PostPosted: Wed Jun 13, 2012 2:53 pm 
Offline

Joined: Tue Jan 27, 2009 8:19 pm
Posts: 349
Just make sure you leave enough length so that it goes far enough into the seat tube to end at or below the lower junction with the top tube. If you want to save the maximum amount of weight you can cut it diagonally so that it is longer at the front when inserted.

Leave a centimeter of leeway to allow for possible height adjustment.


Top
 Profile  
 
PostPosted: Thu Jun 14, 2012 12:20 am 
Offline

Joined: Sat Mar 31, 2012 5:02 am
Posts: 11
Thanks for all of the good thoughts guys. I appreciate all of the responses. I'm also considering switching to the Doric since it doesn't seems as though I need a setback post (note that the saddle is all the way back for proper knee/spindle alignment):

Image

So I'm also not terribly eagerto cut it without knowing all of the facts.

prendrefeu wrote:
Take your seatpost apart.
Weigh the carbon shaft.
Measure the carbon shaft.

Measure the distance you plan on cutting off.
Calculate potential weight savings.

Decide.

:|


It's not that easy with a Dorico Team. The head weighs much more than the shaft. The only true way to accurately calculate g/cm would be to know the difference in weight between the 350 and the 280.

I know for certainty, as a result of this (http://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=69718), that the 350 weighs 235.8 grams. Does anyone know the weight of the 280?

I'm guessing about 35-50 grams of savings but I'm kind of obsessed with calculating it for some reason… OCD??

_________________
2011 Cervélo RS - SRAM Red


Top
 Profile  
 
PostPosted: Thu Jun 14, 2012 1:49 am 
Offline
User avatar

Joined: Fri Feb 11, 2011 3:04 am
Posts: 2359
Location: Mississippi
Yes, it appears you need a zero setback post.....and possibly a bigger frame :noidea:

_________________
Cervelo R3

http://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=125962


Top
 Profile  
 
PostPosted: Thu Jun 14, 2012 2:13 am 
Offline

Joined: Sat Mar 31, 2012 5:02 am
Posts: 11
I can see how you'd possibly conclude that. But I have really long legs and a short torso. The fit is perfect. With a 61 my ass slides off the nose. I have 64cm of reach. Impossible to achieve with a 61cm frame.

_________________
2011 Cervélo RS - SRAM Red


Top
 Profile  
 
PostPosted: Thu Jun 14, 2012 2:19 am 
Offline
User avatar

Joined: Fri Feb 11, 2011 3:04 am
Posts: 2359
Location: Mississippi
Yeah, that's why I put the "no idea" icon.......either wrong frame or outlier body dimensions. Guess its the latter!! Good looking bike, btw!

_________________
Cervelo R3

http://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=125962


Top
 Profile  
 
PostPosted: Thu Jun 14, 2012 2:47 am 
Offline

Joined: Sat Mar 31, 2012 5:02 am
Posts: 11
No worries. I didn't take any offense. And thanks! :)

_________________
2011 Cervélo RS - SRAM Red


Top
 Profile  
 
PostPosted: Thu Jun 14, 2012 1:29 pm 
Offline

Joined: Sun Jul 10, 2011 9:03 am
Posts: 292
If you really wanted to go to the trouble you could use a displacement measurement.
Measure the water volume displaced by the whole thing with the clamp and metal bits removed.
Then measure the water volume displaced by the shaft alone for the length you propose to remove.
The ratio of volume to volume will be the same as weight to weight.

_________________
r o y g b i v


Top
 Profile  
 
PostPosted: Thu Jun 14, 2012 7:15 pm 
Offline

Joined: Tue Sep 20, 2011 8:15 pm
Posts: 177
If someone saddle is tipped that far forward from being level, it almost always means they need lower their saddle a few centimeters and level it out. Or secondly... you're riding the wrong saddle for your body type.

Anyway... with your saddle up that high, I probably would suggest not cutting much off. You want it to go quite far into the frame, otherwise you risk a broken post or even frame.

And you say you need a set-back post... yet it appears in the photo that your saddle is slammed almost all the way FORWARD! You mean a set-back post... to ride in reverse?


Top
 Profile  
 
PostPosted: Thu Jun 14, 2012 8:48 pm 
Offline

Joined: Sat Mar 31, 2012 5:02 am
Posts: 11
Thanks for the tips guys. I'll have to try the water displacement idea.

Regarding set-back/no set-back I see that I chose my words rather poorly. What I meant is that I may want to switch from a set-back (Dorico) to a zero set-back (Doric) hence my desire to not cut right now.

Thanks again!

_________________
2011 Cervélo RS - SRAM Red


Top
 Profile  
 
Posted: Thu Jun 14, 2012 8:48 pm 


Top
  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 15 posts ] 


Who is online

Users browsing this forum: Exabot [Bot] and 43 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:  

   Similar Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. 08 Giant TCR Advanced Team ISP - Mount traditional seatpost?

in Road

locktopus

7

726

Fri Apr 11, 2014 10:04 am

latman View the latest post

There are no new unread posts for this topic. Rose Xeon Team CGF, opinions

in Road

YoKaiser

1

1037

Fri Mar 21, 2014 4:22 pm

vtorstein View the latest post

There are no new unread posts for this topic. Orbea Team Frame Color

in Road

cape

1

455

Fri Sep 27, 2013 5:35 pm

ichobi View the latest post

There are no new unread posts for this topic. Katusha/Movistar Team Bikes

in Road

Valbrona

1

837

Sun Mar 16, 2014 3:55 am

bombertodd View the latest post

There are no new unread posts for this topic. Recent Scott CR1 Pro/Team frameset weight?

in Road

n808

2

524

Wed Apr 23, 2014 2:55 pm

n808 View the latest post


It is currently Wed Sep 17, 2014 12:39 am

All times are UTC + 1 hour




Advertising   –  FAQ   –  Contact   –  Convert   –  About

© Weight Weenies 2000-2013
hosted by starbike.com


How to get rid of these ads? Just register!


Powered by phpBB