Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

add chain links when going from 25-28 cassette?

Notices
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.

add chain links when going from 25-28 cassette?

Old 05-19-14, 10:33 PM
  #1  
tahoeeddie
Senior Member
Thread Starter
 
Join Date: Apr 2013
Posts: 70

Bikes: 2012 Cervelo R3 Team

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
add chain links when going from 25-28 cassette?

i have a road bike, 10 speed cassette 11-25 currently. and i'm thinking about putting in an 11-28. do you know if i need to add links to my chain?

it's a new chain (a couple of months), and the chain was measured off of the 25.
i don't know how much the RD can adjust for putting in a 28.

thanks.
tahoeeddie is offline  
Old 05-20-14, 10:53 AM
  #2  
HillRider
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 32,803

Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!

Mentioned: 37 Post(s)
Tagged: 0 Thread(s)
Quoted: 1649 Post(s)
Likes: 0
Liked 503 Times in 380 Posts
The rear derailleur doesn't define the required chain length. Shift the bike to big-big (large chainring and largest cog) and see if there is any slack and if you can fold the chain over itself at least 4 pins. If so the old chain should clear the newer cassette. If the chain is now the minimal length to just allow big-big with the 25, you need 2 more half links (1" additional length) to clear the 28T.
HillRider is offline  
Old 05-20-14, 06:37 PM
  #3  
tahoeeddie
Senior Member
Thread Starter
 
Join Date: Apr 2013
Posts: 70

Bikes: 2012 Cervelo R3 Team

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Thanks.i ended up just being able to slap the 11-28 on. some slight adjustment to the b-limit and it's all good to go.
tahoeeddie is offline  
Old 05-20-14, 06:49 PM
  #4  
fietsbob
Banned
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 43,599

Bikes: 8

Mentioned: 197 Post(s)
Tagged: 0 Thread(s)
Quoted: 7607 Post(s)
Liked 1,316 Times in 827 Posts
bear in mind the RD strain if you cross chain Big-Big things may stretch too hard .

like the chain is a bit short .. you can get it, forced , to upshift.. but wont come back down under return spring pressure..

but if you shift to the small ring first, consistently, you might get away with it ..


Might be a good time to put a new chain on with the new cassette, anyhow..
fietsbob is offline  
Old 05-20-14, 07:04 PM
  #5  
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 35,964

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 124 Post(s)
Tagged: 1 Thread(s)
Quoted: 4362 Post(s)
Likes: 0
Liked 29 Times in 28 Posts
Originally Posted by tahoeeddie View Post
i have a road bike, 10 speed cassette 11-25 currently. and i'm thinking about putting in an 11-28. do you know if i need to add links to my chain?....
thanks.
How the heck would I know?

But you have the bike and can easily find out for yourself.

Every 2 teeth added to either of the big (bigger, biggest) sprockets calls for 1/2" of additional chain. So adding 3 teeth means you need 1" more chain, which turns out to be the least you can add.

Now you know you need 1" more chain, but that doesn't mean you need to lengthen because the chain may already be long enough. So shift to big/big and see how much chain you have to spare. Pull the lower loop forward at the bottom of the chainring, and note how much you can pull up.

The minimum is just shy of 1" and you need 3/4" more so If you can pull up almost 2", you're in. If you can only pull up 1" or so, you don't have any to spare and will need to lengthen.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Roypw
Bicycle Mechanics
27
11-14-14 12:12 PM
bikemig
Bicycle Mechanics
11
07-28-13 02:35 PM
stowellt
Bicycle Mechanics
10
04-03-12 12:23 PM
gabkr
Bicycle Mechanics
12
03-30-12 08:54 PM
ducati hyp
Road Cycling
4
02-21-11 11:23 AM

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


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.