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  [ 11 posts ] 
Author Message
 Post subject: Sram chain length
PostPosted: Sun Feb 24, 2013 11:50 am 
Offline

Joined: Sun Dec 02, 2012 11:06 pm
Posts: 27
Whilst cutting a new chain to length for my sram force I noticed there were two seemingly contradictory instructions on the site:

The first for their chains shows placing the chain over the big ring and largest cog, and then adding 1 link + power lock (http://cdn.sram.com/cdn/farfuture/lE2r6 ... __2_07.pdf) for sram derailleurs. I.e two additional links in total.

The second specifically for their derailleurs shows the same method as above, but add 2 links + power link. http://cdn.sram.com/cdn/farfuture/c90h_ ... eurs_6.pdf. I.e 3 additional links in total.

I've always done the first option (+ 2 links in total, incl power link).

Anyone else come across this? And what do you generally do?


Top
 Profile  
 
 Post subject: Sram chain length
Posted: Sun Feb 24, 2013 11:50 am 
  • 1.90 € (including 19% VAT)
  • 835 components by SRAM


Top
  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 1:10 pm 
Offline

Joined: Sat May 26, 2012 11:26 pm
Posts: 359
2 links including powerlink using the same method, big ring, big sprocket.

_________________
Evo 5.63kg SL3 6.66 viewtopic.php?f=10&t=110579" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 2:06 pm 
Offline

Joined: Tue Sep 14, 2010 3:28 pm
Posts: 1402
You can find a more practical way of determining chain length at http://www.campagnolo.com/repository/do ... 2_2012.pdf


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 2:35 pm 
Offline

Joined: Mon Jan 21, 2013 9:00 pm
Posts: 31
Go with your add 2 + link method as the first will result in a short chain.

I recently went through the same thing with my red group. the first method gave me 106 links and the second gave me 108. For me the 108 was correct.

I have also found that you can double check your length by running the chain through the rear derailluer and small small in this position the rear derailluer jockey wheels should almost be horizontal. (hope this makes sense)

This might explain it better as well as pics! :mrgreen:

http://www.slowtwitch.com/Tech/The_correct_length_of_your_chain_444.html


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 3:17 pm 
Offline

Joined: Fri Mar 24, 2006 1:26 pm
Posts: 2527
What you're really trying to do is add a minimum of 1 inch of additional chain to the minimum length. If the ends that come together are both the same, then you have to add 1-1/2 inches to get the ends to join. The master link is 1/2 inch of the chain length that you're adding - no different than any other pair of outer plates.

I prefer to use the the little/little method to set my chain length as long as possible. Then you'll never have to worry about having enough chain length, if you change to a cassette with a larger big cog. That's basically what Campy suggests. That same chain length can be used for an 11-23 cassette or 12-29.


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 4:30 pm 
Offline

Joined: Sat Jun 16, 2012 3:12 am
Posts: 157
I am going to buck the trend and suggest not erring on the side of too long. It depends on your derailleur but my last 105 derailleur didn't wrap enough chain (using 2+link method) on my compact (34/50) to keep chain from slapping against chainstay when in small ring and smaller cogs. I now use the 1+link method and seems to work great.


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 5:32 pm 
Offline

Joined: Sat Dec 13, 2003 2:25 am
Posts: 4438
Location: Canada
SRAM chain length is the same as any other chain length. Assuming that you have a ring spread and cassette spread appropriate for your component choices, the selection of the best chain length is pretty simple.

First, set the 'B' screw to fit your cassette. Selecting the smallest sproket and the small chainring. You want to choose the chain length that gives you enough tension to allow the chain to clear the jockey pulley. It is a bit of a fine line between choosing a 'shorter' or a 'longer' chain, as the spread of links sometimes forces a choice between the two. Generally, my recommendation is based on the use to which the bike is to be put.

For an all-purpose bike (or an inexperienced rider), I usually recommend erring on the 'long' side. This is how I set-up my wife's bikes and my girlfriend's bikes. A little bit of chain slap and play may be ok in that application. Also, it may allow the rider to choose a larger cassette for use in the mountains.

For a race bike, the better choice is to err on the 'short' side. The additional tension on the chain may save a dropped chain or a chain-suck problem one of those desperation cross-chain counter-attack 'incidents' that seem to always happen on a bumpy, off-camber change in terrain (hmmmmm. Why does that always seem to happen? :D ) The 'risk' to the derraileur is probably acceptable in a pure racing application where you have no-one to blame but yourself for cross-chaining and throwing 1,200 watts through it (whereas the wife/GF might kill you).


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 5:42 pm 
Offline

Joined: Mon Jan 21, 2013 9:00 pm
Posts: 31
You have a wife and a girlfriend? You are my hero :beerchug: :lol:


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 6:14 pm 
Offline

Joined: Fri Mar 24, 2006 1:26 pm
Posts: 2527
pushstart wrote:
I am going to buck the trend and suggest not erring on the side of too long. It depends on your derailleur but my last 105 derailleur didn't wrap enough chain (using 2+link method) on my compact (34/50) to keep chain from slapping against chainstay when in small ring and smaller cogs. I now use the 1+link method and seems to work great.


If by a link you mean one inch of chain, there is no method that suggests adding 2 inches of chain to the minimum length. If you want the longest possible chain, without it hanging loose in the little/little, you shift into that combo and adjust the length to create some tension on the lower section of chain.

The minimum increment of change to the length is 1 inch and that is actually 2-links, if you use the same terminology used when chains are sold. A 114 link chain will be 57 inches long.

One issue with today's road bikes is the range of largest cogs is likely to be from 23 to 29. That's 1-1/2 inches of chain, but of course, it requires 2 inches of additional length in order to join the chain.

Due to the many possible combinations of large chainring, largest cog and chainstay length, it's rare for a chain not to have some amount of excess length.


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Sun Feb 24, 2013 10:00 pm 
Offline

Joined: Sun Dec 02, 2012 11:06 pm
Posts: 27
Thanks for the many helpful replies! The method I've used is probably on the short side, but not by much. The alternative is probably just on the longer side, but not by much. I've been using and racing with the shorter length for many years without a problem on a 12-25, so might stick with it. Cheers


Top
 Profile  
 
 Post subject: Re: Sram chain length
PostPosted: Mon Feb 25, 2013 5:34 am 
Offline

Joined: Fri Aug 31, 2012 6:32 pm
Posts: 134
You can't physically add 2 links + powerlock so I think your second link is just misleading.


Top
 Profile  
 
 Post subject: Re: Sram chain length
Posted: Mon Feb 25, 2013 5:34 am 
  • 1.90 € (including 19% VAT)
  • 835 components by SRAM


Top
  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 11 posts ] 


Who is online

Users browsing this forum: bikerjulio, Brandt, Estelja, Fattrucker, fishyskawa, Google Adsense [Bot], skidmark, tomgag, velo2453 and 65 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. New chain length difference

in Road

pdlpsher1

2

458

Tue Sep 10, 2013 3:38 am

pdlpsher1 View the latest post

There are no new unread posts for this topic. Going for larger chainrings - chain length?

in Road

Kermithimself

5

408

Wed Aug 14, 2013 9:36 pm

bikerjulio View the latest post

There are no new unread posts for this topic. Cassette Mixing & Chain Length

in Road

Ltoddokc

4

115

Wed Jul 23, 2014 8:25 pm

FIJIGabe View the latest post

There are no new unread posts for this topic. 9000 cranks with SRAM FD and chain

in Road

itsacarr

1

283

Fri Feb 07, 2014 11:18 pm

FastforaSlowGuy View the latest post

There are no new unread posts for this topic. 2011 SRAM Red Crankset On 2012/13 FD Yaw - chain rub?

in Road

applebaconator

14

1587

Fri Dec 13, 2013 9:26 pm

Mr.Gib View the latest post


It is currently Wed Jul 23, 2014 9:37 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