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

Front derailleur skips the middle gear

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.

Front derailleur skips the middle gear

Old 04-08-17, 03:27 AM
  #1  
longhaulbiker
Newbie
Thread Starter
 
Join Date: Apr 2017
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Front derailleur skips the middle gear

Hi,

My front derailleur wont pull the second gear and I can't figure out why.

The cable is taut but not tight, the low limit screw is blocking the inner plate of the derailleur so that this one almost touches the chain, and my derailleur has received a good shower of WD40. The cable and cable housing are new too.

What happens is that when I try to put the second gear the derailleur will instead go straight into the 3rd one, skipping the middle gear altogether.

Is there anything that I am missing maybe ?

Thanks
longhaulbiker is offline  
Old 04-08-17, 06:30 AM
  #2  
dsbrantjr
Senior Member
 
dsbrantjr's Avatar
 
Join Date: Sep 2010
Location: Roswell, GA
Posts: 6,228

Bikes: '93 Trek 750, '92 Schwinn Crisscross, '93 Mongoose Alta

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 654 Post(s)
Likes: 0
Liked 48 Times in 44 Posts
The new shift wire and housing give a possible clue.
Do you have the shift wire routed properly vs the clamp screw? Many Shimano derailleurs non-obviously require the wire to go OVER the little tab near the screw. If you go under the tab direct to the screw, it shortens the lever arm and makes the shifter throw greater than intended.
dsbrantjr is online now  
Old 04-08-17, 07:47 AM
  #3  
XCSKIBUM
Cantankerous Old Fart
 
XCSKIBUM's Avatar
 
Join Date: Mar 2010
Location: On the Tundra of Northern NY State, almost Canada eh?
Posts: 188

Bikes: TBD

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by dsbrantjr View Post
The new shift wire and housing give a possible clue.
Do you have the shift wire routed properly vs the clamp screw? Many Shimano derailleurs non-obviously require the wire to go OVER the little tab near the screw. If you go under the tab direct to the screw, it shortens the lever arm and makes the shifter throw greater than intended.


After checking the above:

Screw the cable adjuster all the way in, then back out a few turns. With the rear derailleur in one of the "middle cogs" place the shifter in the middle chainring position and adjust the cable length at the derailleur so that the chain runs in the center of the derailleur. You can now fine tune the adjustment with the cable adjustment.

That;s how I do it when a cable is changed. For more complete, in depth instructions;

HERE ARE SOME INSTRUCTION FROM PARK TOOL

Last edited by XCSKIBUM; 04-08-17 at 07:52 AM.
XCSKIBUM is offline  
Old 04-08-17, 09:25 AM
  #4  
Andrew R Stewart 
Senior Member
 
Andrew R Stewart's Avatar
 
Join Date: Feb 2012
Location: Rochester, NY
Posts: 11,615

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Raleigh Pro, Trek Cycle Cross, Mongoose tomac ATB, GT Bravado ATB, JCP Folder

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1734 Post(s)
Liked 47 Times in 34 Posts
Can the OP shift the ft der with only pulling the bare inner cable (and not the control lever)? If so then the der's adjustments are close to correct. Then the next issue is as mentioned already, the communication link isn't set right or the lever has issues. But one can also check the lever by disconnection the cable from the der and while holding the loose cable end cycle the lever threw it's range to test it.


But since we don't know any actual specs we can only speculate. Is the lever an indexed one? What's the brand? Model? Road or other? Classic case of too little info to really be able to be specific to the OP's problem in replies. Andy.
Andrew R Stewart is offline  
Old 04-08-17, 04:35 PM
  #5  
longhaulbiker
Newbie
Thread Starter
 
Join Date: Apr 2017
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by dsbrantjr View Post
The new shift wire and housing give a possible clue.
Do you have the shift wire routed properly vs the clamp screw? Many Shimano derailleurs non-obviously require the wire to go OVER the little tab near the screw. If you go under the tab direct to the screw, it shortens the lever arm and makes the shifter throw greater than intended.
Wow, spot on. I'd have never figure that out by myself since the tab seems to actually have the entire opposite role, more so to hold the cable inside before it's rolled around the screw.

The lever now works soft and natural and I can see the derailleur shifting efortlessly.

Another thing now is that it doesnt shift from middle to first gear but I attribute that to the cable tension/limit screws, I'll run through everything again to make sure it's set properly.

Really appreciate all this anonymous help, thanks everyone !
longhaulbiker is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
AtariBaby
Tandem Cycling
5
09-20-11 12:25 PM
illwafer
Classic & Vintage
1
05-09-10 02:55 PM
dguest
Fifty Plus (50+)
17
11-01-08 04:33 PM
Desp
Mountain Biking
4
08-16-06 07:03 PM

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

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.