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

Rear Derailleur in horizontal position

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.

Rear Derailleur in horizontal position

Old 01-16-21, 09:07 PM
  #1  
Charlie B
Junior Member
Thread Starter
 
Join Date: Jan 2021
Posts: 11
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
Rear Derailleur in horizontal position

Hello,

The rear derailleur on my son's CX bike is in horizontal position when it is on the smallest cog of the cassette. Also it does not shift properly anymore and cannot shift to the largest cogs anymore. It seems that the chain is too long but what is strange to me is that there has not been any problems for the past 6 months with the same chain. I checke the chain wear and that is ok. Also cassette is in good order. Could it be that the RD is damaged and that this is resulting in this horizontal position when on the smallest cog. Or any other reason and how to fix this?
Charlie B is offline  
Old 01-16-21, 09:16 PM
  #2  
cxwrench
Senior Member
 
cxwrench's Avatar
 
Join Date: Jul 2013
Location: Nor-Cal
Posts: 1,145

Bikes: lots

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 471 Post(s)
Liked 504 Times in 294 Posts
Obviously it could be damaged. Would be great to see photos, guess we'll wait til you can do that.
cxwrench is offline  
Old 01-16-21, 09:26 PM
  #3  
Charlie B
Junior Member
Thread Starter
 
Join Date: Jan 2021
Posts: 11
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
I would like to post a photo of it. But I understood I am not able to do this now as I just became a member. The RD does not appear to be damaged to me.
Charlie B is offline  
Old 01-16-21, 09:34 PM
  #4  
cxwrench
Senior Member
 
cxwrench's Avatar
 
Join Date: Jul 2013
Location: Nor-Cal
Posts: 1,145

Bikes: lots

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 471 Post(s)
Liked 504 Times in 294 Posts
How does it feel if you push down on the pulley cage? Or push/pull on the main body? Is there a distinct lack of spring tension?
cxwrench is offline  
Old 01-17-21, 03:09 AM
  #5  
cobba
Senior Member
 
Join Date: Aug 2006
Posts: 1,802
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 142 Post(s)
Likes: 0
Liked 27 Times in 23 Posts
Originally Posted by Charlie B View Post
I would like to post a photo of it. But I understood I am not able to do this now as I just became a member.
Try uploading some photos to the gallery: https://www.bikeforums.net/g/


If you can uploaded them, make a comment in this thread to let us know.
cobba is offline  
Old 01-18-21, 03:46 PM
  #6  
Charlie B
Junior Member
Thread Starter
 
Join Date: Jan 2021
Posts: 11
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
push down on the pulley cage feels normal also on the main body. There does not seem to be a distinct lack of spring tension as well
Charlie B is offline  
Old 01-18-21, 03:53 PM
  #7  
Iride01
Hits [ENTER] b4 thinking
 
Iride01's Avatar
 
Join Date: Jul 2017
Location: Mississippi
Posts: 5,666

Bikes: '20 Tarmac Disc Comp '91 Schwinn Paramount '78 Raleigh Competition GS

Mentioned: 27 Post(s)
Tagged: 0 Thread(s)
Quoted: 2198 Post(s)
Liked 936 Times in 702 Posts
Bike is all original stuff? No one has replaced the chain or changed the cassette or chain rings?
Iride01 is offline  
Old 01-18-21, 04:06 PM
  #8  
Charlie B
Junior Member
Thread Starter
 
Join Date: Jan 2021
Posts: 11
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
Cassette and chain ring have not been replaced and my son has been riding fine on it the for past 4 months or os. Several high intensity CX trainings without any issue
Charlie B is offline  
Old 01-18-21, 04:53 PM
  #9  
Kovkov
Senior Member
 
Kovkov's Avatar
 
Join Date: Nov 2017
Location: Switzerland
Posts: 376

Bikes: 1957 Alpa Special, 1963 Condor Delta, 1967 Tigra Sprint, 1977 Oltenia, 1987 Mondia, 1965 Staco de luxe, 1969 Amberg

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 113 Post(s)
Liked 66 Times in 36 Posts
If the chain and the rd are ok the only thing i can think of is a compromised hanger or that the wheel slipped forward. For the latter to happen it would need horizontal dropouts or the dropouts and/or the rear triangle are compromised in some way.
Kovkov is offline  
Old 01-19-21, 10:59 AM
  #10  
Redbullet
Senior Member
 
Join Date: Aug 2015
Posts: 364
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 116 Post(s)
Liked 11 Times in 9 Posts
Does the derailleur have a "B screw"? Was it accidentally unscrewed?
Redbullet is offline  
Old 01-19-21, 11:26 AM
  #11  
rydabent
Senior Member
 
Join Date: Apr 2010
Location: Lincoln Ne
Posts: 8,780

Bikes: RANS Stratus TerraTrike Tour II

Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 2191 Post(s)
Liked 552 Times in 331 Posts
Originally Posted by Redbullet View Post
Does the derailleur have a "B screw"? Was it accidentally unscrewed?
The "B" screw is not for chain tension.

BTW normally the RD is only mostly horizontal when your are in the large gears both front and rear. I would guess it is a spring problem.
rydabent is offline  
Old 01-19-21, 12:47 PM
  #12  
ClydeClydeson
Senior Member
 
Join Date: Mar 2019
Posts: 423
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 136 Post(s)
Liked 150 Times in 110 Posts
The 'horizontal position' you refer to - I assume you mean the jockey wheels are lined up horizontaly.

As long as the chain is not dragging across itself in this position then there is nothing to worry about.
As for the trouble shifting into larger cogs, this is likely unrelated. I suspect the poor shifting begain and during inspection you saw that the derailleur was pointing straight back.

It is possible the derailleur hanger is bent, but this almost always results in the shifting going too far toward the larger cogs... unless the wheel was off and the derailleur took a whack from behind to bend the hanger in the less common outward direction.

Once you determine if the hanger is straight (bike shops have a tool for this) then you just need to ensure the cable is properly connected and running smooth, the hanger is properly tightened and the wheel is in straight and tight, then look at the derailleur setup from step 1 (check that limit screws are set properly). Then step two (set cable position/tension so the derailleur indexes with the clicks in the shifter).
ClydeClydeson is offline  
Likes For ClydeClydeson:
Old 01-19-21, 02:13 PM
  #13  
Redbullet
Senior Member
 
Join Date: Aug 2015
Posts: 364
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 116 Post(s)
Liked 11 Times in 9 Posts
Originally Posted by rydabent View Post
The "B" screw is not for chain tension.

BTW normally the RD is only mostly horizontal when your are in the large gears both front and rear. I would guess it is a spring problem.
Indeed, B screw is not for adjusting the chain tension (although it might bring a very small help in extreme situations on "small - small" positions if the chain is almost too long and the spring at the lower limit).
But the OP complains of:
1. "Horizontal position": if this means horizontal cage, then is good to know that unscrewing B screw will pull the derailleur cage toward the horizontal position, especially on smaller cogs.
2. "Can not shift in larger cogs anymore": Unscrewing the B screw will change geometry and bring the upper pulley closer and closer to the cogs (vertically). If unscrewed too much, then, there will be not enough space between the upper pulley and the cogs and the chain can not "find" the space to lift up (to shift up) on larger cog. It happens especially at the largest cog (or maybe the largest 2 cogs, depending on cassette type).
Furthermore, the op. said he can't feel a lack of spring tension and even if he did, I think it should create issues around the small cogs, not around the large ones, where springs tension increases.

Sure, the above is just a scenario, there are also other possible reasons.

Last edited by Redbullet; 01-19-21 at 02:16 PM.
Redbullet is offline  
Old 01-19-21, 10:51 PM
  #14  
rydabent
Senior Member
 
Join Date: Apr 2010
Location: Lincoln Ne
Posts: 8,780

Bikes: RANS Stratus TerraTrike Tour II

Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 2191 Post(s)
Liked 552 Times in 331 Posts
Originally Posted by Redbullet View Post
Indeed, B screw is not for adjusting the chain tension (although it might bring a very small help in extreme situations on "small - small" positions if the chain is almost too long and the spring at the lower limit).
But the OP complains of:
1. "Horizontal position": if this means horizontal cage, then is good to know that unscrewing B screw will pull the derailleur cage toward the horizontal position, especially on smaller cogs.
2. "Can not shift in larger cogs anymore": Unscrewing the B screw will change geometry and bring the upper pulley closer and closer to the cogs (vertically). If unscrewed too much, then, there will be not enough space between the upper pulley and the cogs and the chain can not "find" the space to lift up (to shift up) on larger cog. It happens especially at the largest cog (or maybe the largest 2 cogs, depending on cassette type).
Furthermore, the op. said he can't feel a lack of spring tension and even if he did, I think it should create issues around the small cogs, not around the large ones, where springs tension increases.

Sure, the above is just a scenario, there are also other possible reasons.
Actually the "B" screw is there to adjust the jockey wheel to cassette clearance to the largest cog in the cassette. My Sram adjust is listed at 6mm for instance.

If the OP is say horizontal I am assuming that he mean in big gears the bottom tension wheel of his RD is pulled clear forward almost to the horizontal. That can happen when the chain is too short.

Last edited by rydabent; 01-19-21 at 10:54 PM.
rydabent is offline  
Old 01-20-21, 06:23 AM
  #15  
shelbyfv
Senior Member
 
shelbyfv's Avatar
 
Join Date: Jun 2007
Location: TN
Posts: 7,876
Mentioned: 29 Post(s)
Tagged: 0 Thread(s)
Quoted: 2070 Post(s)
Liked 1,796 Times in 976 Posts
Originally Posted by rydabent View Post
If the OP is say horizontal I am assuming that he mean in big gears the bottom tension wheel of his RD is pulled clear forward almost to the horizontal. That can happen when the chain is too short.
His concern is with the position when in the small cog, see his original post.
shelbyfv is offline  
Old 01-20-21, 06:36 AM
  #16  
dsaul
Senior Member
 
Join Date: Jan 2013
Location: South Jersey
Posts: 1,842
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 559 Post(s)
Liked 363 Times in 261 Posts
It is really hard to diagnose without pictures or at least some details on the rear derailleur and frame, but it sounds like the b-tension screw or plate is not properly hooked on the derailleur hanger. In the case of derailleurs that use a metal plate or tab that hooks onto the hanger for b-tension, it it easy to mount the derailleur without hooking that plate on the hanger. The derailleur may function ok for a while, but eventually the derailleur will rotate around the mounting bolt and cause the issues that the OP describes.
dsaul is offline  
Old 01-20-21, 07:33 AM
  #17  
Trakhak
Senior Member
 
Join Date: Jan 2005
Location: Baltimore, MD
Posts: 2,463
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 743 Post(s)
Liked 436 Times in 271 Posts
If you mean that the problem occurs in the small/small combination, that gear combination should be avoided for several reasons, among which a horizontal derailleur cage would probably be one of the less significant.
Trakhak is offline  
Old 01-20-21, 07:58 AM
  #18  
Kapusta
Cyclochondriac
 
Join Date: Feb 2017
Posts: 4,096
Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 1761 Post(s)
Liked 1,022 Times in 614 Posts
If it has been shifting fine for 6 months than the chain length is unlikely to be the problem.

Have you adjusted the cable tension? That is the most obvious first thing to look at first.

Also, the hangar could be bent.

As far as chain length, look up the manufacturer’s instructions to determine proper length if you are interested.
Kapusta is offline  
Old 01-25-21, 11:36 AM
  #19  
Charlie B
Junior Member
Thread Starter
 
Join Date: Jan 2021
Posts: 11
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
Charlie B is offline  
Old 01-25-21, 11:41 AM
  #20  
curbtender
Senior Member
 
curbtender's Avatar
 
Join Date: Mar 2007
Location: SF Bay Area, East bay
Posts: 6,631

Bikes: Marinoni, Kestral 200 2002 Trek 5200, KHS Flite, Koga Miyata, Schwinn Spitfire 5, Schwinn Speedster, Mondia Special, Univega Alpina, Miyata team Ti, MB3

Mentioned: 40 Post(s)
Tagged: 0 Thread(s)
Quoted: 925 Post(s)
Liked 443 Times in 316 Posts
Looks right. Could use a clean and oil.
curbtender is offline  
Old 01-25-21, 11:42 AM
  #21  
cxwrench
Senior Member
 
cxwrench's Avatar
 
Join Date: Jul 2013
Location: Nor-Cal
Posts: 1,145

Bikes: lots

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 471 Post(s)
Liked 504 Times in 294 Posts
What's wrong with that? If the bike is in the smallest cog and small ring (if it has 2) that is fine. It can't have changed because the orientation of the pulley cage is governed by chain length. In other words it can't be in any other position. The bike is a mess, it should be cleaned.
cxwrench is offline  

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.