What are these parts and what's the best way to adjust them?
07-11-12, 05:25 PM
#1
Newbie
Thread Starter
Join Date: Jul 2012
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
What are these parts and what's the best way to adjust them?
These pics are from my Trek FX 7.2. My chain has been rattling and when I brought it in to have it looked at, the guy said he just made a minor adjustment and it's fixed. When I asked what he did, he told me about these knobs and that they just need a small quarter turn to adjust.
I'd like a little more insight as to what these are and more details about how to adjust them.
Thanks!
I'd like a little more insight as to what these are and more details about how to adjust them.
Thanks!
07-11-12, 05:29 PM
#2
Senior Member
Join Date: Mar 2005
Location: New York City
Posts: 875
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
They are barrel adjusters. They essentially will release or add tension to the derailleur cable to adjust the shifting & to compensate for cable stretch.
07-11-12, 05:32 PM
#3
Mechanic/Tourist
Google derailleur adjustment - Sheldonbrown and Parktool sites are popular but try a few. It's helpful to know more than just what the barrel adjusters do - you need an overall understanding of how the derailleurs operate.
07-11-12, 06:06 PM
#5
Senior Member
Join Date: Jun 2011
Posts: 157
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Too much tension and you'll experience hesitation shifting to higher gears; too little and you'll have hesitation or missed shifts trying to go to lower gears. But before you adust the cable tension you first want set the high and low limits of the derailleur travel, so go to the websites listed above to learn how the various adjustments interact.
When you have everthing adjusted properly you'll get smooth, quick shifts with little noise.
When you have everthing adjusted properly you'll get smooth, quick shifts with little noise.
07-11-12, 06:11 PM
#6
Senior Member
Join Date: Jun 2012
Location: Rochester, NY
Posts: 932
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Yes, it's very important to learn this stuff! I've got two left thumbs when it comes to mechanical stuff but I've learned to adjust my derailleurs and brakes. The Sheldon Brown site is very good.
07-11-12, 06:40 PM
#7
Senior Member
07-11-12, 07:04 PM
#8
Mechanic/Tourist
07-11-12, 08:09 PM
#9
Senior Member
Join Date: Jul 2002
Posts: 6,956
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 6 Times
in
5 Posts
I'm nitpicking, but "tension" isn't really the right word. They actually change the effective length of the cable's path. The tension on the cables is provided by the return springs in the derailleurs, and with a few exceptions, that's not adjustable.
07-11-12, 08:27 PM
#10
Senior Member
Join Date: Sep 2010
Location: Roswell, GA
Posts: 8,319
Bikes: '93 Trek 750, '92 Schwinn Crisscross, '93 Mongoose Alta
Mentioned: 30 Post(s)
Tagged: 0 Thread(s)
Quoted: 1438 Post(s)
Liked 1,092 Times
in
723 Posts
mechBgon: Thanks for nitpicking; distinguishing cable tension versus length is an important distinction to make in having a clear understanding how the shifting system works and what the adjustments actually do.
Thread
Thread Starter
Forum
Replies
Last Post
hcgaloi
Bicycle Mechanics
24
09-29-21 04:14 AM
kalash74
Bicycle Mechanics
5
02-06-17 02:17 PM
