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




Post new topic Reply to topic  [ 18 posts ] 
Go to page 1, 2  Next
Author Message
PostPosted: Tue Jan 21, 2014 3:04 am 
Offline

Joined: Fri Jun 01, 2012 6:40 pm
Posts: 196
Are there any Chinese carbon disc specific rims out there? Particularly for CX. I'm actually interested in both tubular and clincher varieties, too.

It seems silly to buy a rim with a brake track when it's not needed and it seems potentially destructive to buy a rim that may not be built for the forces being applied at the spoke holes due to the disc brakes.

Any thoughts? Can one use a 29" MTB rim for this?


Top
 Profile  
 
Posted: Tue Jan 21, 2014 3:04 am 


Top
  
 
PostPosted: Tue Jan 21, 2014 9:33 pm 
Offline

Joined: Tue Nov 11, 2003 9:47 pm
Posts: 1804
Location: Santa Cruz, California, USA
You can use 29er rims. But see http://twentynineinches.com/2009/01/15/ ... -29er-rim/
Light-bicycle has some disc CF 29er rims that a bunch of people on mtbr are using.


Top
 Profile  
 
PostPosted: Wed Jan 22, 2014 7:27 pm 
Offline
User avatar

Joined: Mon Nov 02, 2009 8:38 pm
Posts: 292
...although some people claim it's not always quite that simple: http://paolocoppo.drupalgardens.com/con ... ake-matter

(I haven't tried though, and it may only be a problem with tubeless specific rims, I'm not sure.)

I'm also interested in answers to the OP's question. There are certainly already Chinese carbon 29er wheels. There are also plenty of matte black road options (Farsports etc.) with fairly unobtrusive brake tracks.

_________________
Blog: http://thesetbackpost.com/


Top
 Profile  
 
PostPosted: Wed Jan 22, 2014 7:36 pm 
Offline

Joined: Tue Nov 11, 2003 9:47 pm
Posts: 1804
Location: Santa Cruz, California, USA
One other problem I just though of is inflation pressure limits. 29er rims often have low limits like 45psi or even lower. Perhaps not a problem for CX but 45 psi would not be good for road use.


Top
 Profile  
 
PostPosted: Thu Jan 23, 2014 11:00 pm 
Offline
in the industry

Joined: Sat May 12, 2012 7:25 pm
Posts: 1592
Location: Glermsford, Suffolk U.K
No carbon disc specific rims for CX yet, which is a shame. The MTB rims I think will be a comprimise to far unless you are running CX tyres and riding off road then low pressure is all you want.

_________________
www.thecycleclinic.co.uk


Top
 Profile  
 
PostPosted: Fri Jan 24, 2014 6:51 pm 
Offline

Joined: Mon May 30, 2011 11:41 am
Posts: 23
I think you can custom order light bicycle rims without brake track. Gonna do so myself with their tubeless road rims.


Top
 Profile  
 
PostPosted: Mon Feb 24, 2014 6:26 pm 
Offline

Joined: Sun Dec 08, 2013 11:43 pm
Posts: 28
Location: Oldeholtpade
I think you can buy track rims wich have more spoke holes but they are generally tubular only. They shouldn't have a brake surface tho.


Top
 Profile  
 
PostPosted: Tue Feb 25, 2014 9:49 am 
Offline

Joined: Sat Jun 16, 2012 3:12 am
Posts: 237
Yes, my LB U45 rims have no brake track. I didn't know to ask; I just told the rims were for disc-brake wheels and they spec'd them without brake tracks in the invoice. I imagine these would work well for cx (I am using them for road).

Image


Top
 Profile  
 
PostPosted: Wed Feb 26, 2014 1:12 am 
Offline
in the industry

Joined: Sat May 12, 2012 7:25 pm
Posts: 1592
Location: Glermsford, Suffolk U.K
No brake track does not mean the rim has been designed as disc specific. There should be a big weight saving for a disc specific rim. I doubt these rims show a weight saving so to me they are not properly disc specific.

_________________
www.thecycleclinic.co.uk


Top
 Profile  
 
PostPosted: Wed Feb 26, 2014 2:15 am 
Offline

Joined: Sat Jun 16, 2012 3:12 am
Posts: 237
No need to quote above

They are not disc specific, in design, sure. I believe Enve makes a road disc specific rim? In any event, I think the weight savings remain to be proven. There are plenty of disc-specific alloy rims and they don't seem to be saving any significant weight.


Top
 Profile  
 
PostPosted: Wed Feb 26, 2014 8:09 am 
Offline
Formerly known as wassertreter

Joined: Tue Apr 12, 2011 8:08 am
Posts: 2017
Location: Pedal Square
Oh there are lots of very light aluminium MTB rims for disc-only use, but probably the lower max pressure (than road rims) also allows to save material, in addition to not needing a brake track.

_________________
Bikes: Raw Ti, 650b flatbar CX


Top
 Profile  
 
PostPosted: Wed Feb 26, 2014 5:33 pm 
Offline

Joined: Sat Oct 09, 2010 11:42 am
Posts: 51
Weight savings for disc-specific road-pressure-capable clincher rims will likely prove not to be very big. At say 100 psi, the rim structure is working harder in its "tire attachment" role than it is in its brake track role. Bead hook depths can be lowered to alleviate this, but wider rims need structure to support their shapes. Add full, no limits road tubeless capacity to them and you might do as well as being at net even with a current rim-brake rim.

_________________
http://www.novemberbicycles.com


Top
 Profile  
 
PostPosted: Thu Feb 27, 2014 1:50 am 
Offline

Joined: Sat Jun 16, 2012 3:12 am
Posts: 237
wassertreter wrote:
Oh there are lots of very light aluminium MTB rims for disc-only use, but probably the lower max pressure (than road rims) also allows to save material, in addition to not needing a brake track.


So there are also lots of very light road rims with brake tracks. It is hard to find apples-to-apples comparisons, but e.g. Stans Alpha 340 rims (rim-brake) weigh 10g less than Iron Cross (disc-only, a little wider but also shallower). That is just one mfr, obviously, and not a great comparison but it suggests that any savings will be in the handful of grams. I would love to be wrong, of course.


Top
 Profile  
 
PostPosted: Thu Feb 27, 2014 8:46 am 
Offline

Joined: Fri Apr 20, 2012 9:04 pm
Posts: 241
I have used farsports 38mm cx on my bike. Whilst the moulding looks like it has a brake track, I don't believe it can be used for braking. The composition certainly looks different to the similar rims on my non disc road bike
Image


Top
 Profile  
 
Posted: Thu Feb 27, 2014 8:46 am 


Top
  
 
PostPosted: Sun Mar 02, 2014 5:44 pm 
Offline
in the industry

Joined: Sat May 12, 2012 7:25 pm
Posts: 1592
Location: Glermsford, Suffolk U.K
Well Ryde have a 25mm deep alloy climcher disc only rim that weighs 337g. So there is a weight saving for proper disc specific rims. This rim has an internal width of 15mm, can hold 1200N spoke tension and will take tyres inflated to 120 psi. So proven it is it is just no one has done it for carbon yet.

_________________
www.thecycleclinic.co.uk


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 18 posts ] 
Go to page 1, 2  Next


Who is online

Users browsing this forum: oreoboreo, Orfitinho and 6 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. Chinese Carbon Rims for Cross—Any Experiences?

in Cyclocross / Touring

jonbek

10

1596

Wed Nov 12, 2014 6:44 pm

gummee View the latest post

There are no new unread posts for this topic. Disc-Only Carbon Tubular Rims; Weight Savings?

in Road

mca56

3

443

Wed Sep 03, 2014 12:44 am

964Cup View the latest post

There are no new unread posts for this topic. New Pacenti SL25 disc specific rim on the way.

in Everything wheels

ergott

11

711

Wed Nov 12, 2014 3:14 am

jooo View the latest post

There are no new unread posts for this topic. chinese carbon saddles

[ Go to page: 1, 2 ]

in MTB

chris47

21

2233

Sun Sep 28, 2014 6:09 am

Benno View the latest post

There are no new unread posts for this topic. velochampion carbon specific brake pads

in Everything wheels

bobalou

1

225

Sat Jun 21, 2014 10:09 pm

eric View the latest post


It is currently Sat Dec 20, 2014 3:38 pm

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