Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

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.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 03-08-14, 12:24 PM   #1
bikerider3
Junior Member
Thread Starter
 
Join Date: Jan 2014
Bikes:
Posts: 21
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Front derailleur set screw isnt moving anything

Hello im new to this. I was just working on trying to take out the rub on my front derailleur. Ive adjusted the inside movement (34x27) And i can see how the inside set screw moves the derailleur in and out with the slightest turn. And easily set it where it needs to be.

But now i shift to the 50x11 and the derailleur rubs in the last few hardest gears. Ive turned the outside set screw all the way in and all the way out but it doesnt move the front derailleur.
when i pull on the cable it moves the derailleur out and stays clear of the chain. But when i shift to the small ring and back to the big it goes back to rubbing again. Is this an issue with the cable tension? Ive tried tightening and losing the cable with the adjuster near the handle bars. The cable seems pretty tight right now on the big ring. Its even tighter than the cable when the rear derailleur is in the biggest cassette. Im new to this so im pretty stumped. Does the derailleur need oil, is it broken? It doesnt look bent at all as its inline with the chainring.

Its a newer bike 2011 caad 10 with 105 components. If anyone can help me out it would be greatly appreciated as im set to head out on a ride in a couple hours. Id love to figure this out.

Last edited by bikerider3; 03-08-14 at 12:27 PM.
bikerider3 is offline   Reply With Quote
Old 03-08-14, 12:31 PM   #2
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 19,670
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 451 Post(s)
its a stroke limit screw it should only be used to set up how far the FD moves

You Describe the classic STI Issue, there is no fine tuning after the shift , like friction shifting

or I expect that as it comes up so often .

the rubbing comes from gear selection in the back .. if you use it as designed , no cross chain combinations.
then the rubbing will be minimal and only at the edges of the gear combinations in best alignment.
fietsbob is offline   Reply With Quote
Old 03-08-14, 12:34 PM   #3
cny-bikeman 
Mechanic/Tourist
 
Join Date: Apr 2007
Location: Syracuse, NY
Bikes: 2008 Novara Randonee - love it. Would have more bikes if I had time to ride them all. Previous bikes: 1968 Motobecane Mirage, 1972 Moto Grand Jubilee (my fav), Jackson Rake 16, 1983 C'dale ST500.
Posts: 6,277
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 35 Post(s)
It's a cable issue. The spring holds the derailleur against the inner stop unless the cable is too tight. The cable pushes the derailleur against the outer stop unless the cable is too loose. Google adjust derailleur, parktool.com and sheldonbrown.com are the best. The outer limit is best adjusted by pulling on the cable - one set you work on cable "tension" to get it to travel to the stop.
__________________
There's no such thing as a routine repair.

Don't tell me what "should" be - either it is, it isn't, or do something about it.

If you think I'm being blunt take it as a compliment - if I thought you were too weak to handle the truth or a strong opinion I would not bother.

Please take the time to post clearly so we can answer quickly. All lowercase and multiple typos makes for a hard read. Thanks!

Last edited by cny-bikeman; 03-08-14 at 03:15 PM.
cny-bikeman is offline   Reply With Quote
Old 03-08-14, 12:50 PM   #4
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 29,671
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 223 Post(s)
This might help you get a sense of what your problem is.

Picture an elevator.

It hangs from a cable. There are stops at the top and bottom of the shaft to keep it from crashing into the end.

Now picture that the bottom stop is adjustable, and that the elevator rests on it for the basement height (real elevators don't, just an example). So raising or lowering that stop would raise or lower the elevator for the basement stop, but would have no effect anywhere else when the elevator is hanging from the cable.

Therefore, each floor stop position (except the basement) depends on the length of cable spooled out from the top of the shaft.

Now for the top of shaft stop. It wouldn't affect anything, or ever move the elevator. It only comes into play when the elevator is at the top of the shaft, where the stop keeps it from going too far and crashing.

Substitute limit for stop, and you have a decent mental picture of how derailleurs work.
__________________
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.

Last edited by FBinNY; 03-08-14 at 01:01 PM.
FBinNY is offline   Reply With Quote
Old 03-08-14, 01:09 PM   #5
bikerider3
Junior Member
Thread Starter
 
Join Date: Jan 2014
Bikes:
Posts: 21
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by fietsbob View Post
its a stroke limit screw it should only be used to set up how far the FD moves

You Describe the classic STI Issue, there is no fine tuning after the shift , like friction shifting

or I expect that as it comes up so often .

the rubbing comes from gear selection in the back .. if you use it as designed , no cross chain combinations.
then the rubbing will be minimal and only at the edges of the gear combinations in best alignment.
Youre right it is very minimal rubbing only in the last few gears, not really making much noise. But the quick release link always hits when it makes its way around and makes a rubbing noise. I still dont understand why i dont see the derailleur move at all when i turn the outer set screw. The front derailleur right now is making a loud clanking when i shift from big chain ring to small. I know its not right. Will turning the outer screw one way or the other make for a smoother shift?
bikerider3 is offline   Reply With Quote
Old 03-08-14, 01:12 PM   #6
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 29,671
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 223 Post(s)
Quote:
Originally Posted by bikerider3 View Post
.... I still dont understand why i dont see the derailleur move at all when i turn the outer set screw. The front derailleur right now is making a loud clanking when i shift from big chain ring to small. I know its not right. Will turning the outer screw one way or the other make for a smoother shift?
Read my post No.4 above and don't touch the bike until you have a good sense of how the FD works.

After that you'll understand why moving your outer limit doesn't change anything except your ability to shift to the big ring. When finished, correctly adjust the outer limit so the FD shifts smoothly and cleanly to the big ring, without going too far and pushing the chain over the top.
__________________
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   Reply With Quote
Old 03-08-14, 01:22 PM   #7
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 19,670
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 451 Post(s)
I 'm +1 with FB , I adjust limit screws before I even attach the cable, in bare frame setups
then maybe back off the outer one if it requires more stroke to climb up to the outer ring

but not much or the chain goes off entirely..
fietsbob is offline   Reply With Quote
Old 03-08-14, 01:50 PM   #8
bikerider3
Junior Member
Thread Starter
 
Join Date: Jan 2014
Bikes:
Posts: 21
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by FBinNY View Post
Read my post No.4 above and don't touch the bike until you have a good sense of how the FD works.

After that you'll understand why moving your outer limit doesn't change anything except your ability to shift to the big ring. When finished, correctly adjust the outer limit so the FD shifts smoothly and cleanly to the big ring, without going too far and pushing the chain over the top.
Ok thanks youre right i really need to download the park book and read thoroughly. I did manage to adjust it decently smooth enough for now ill do some reading up.
Thanks everyone for your helpful replies.
bikerider3 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -6. The time now is 06:21 AM.