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

Front Derailleur Height

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.

Front Derailleur Height

Old 05-06-05, 08:19 AM
  #1  
No one carries the DogBoy
Thread Starter
 
Join Date: Feb 2004
Location: Upper Midwest USA
Posts: 2,320

Bikes: Roubaix Expert Di2, Jamis Renegade, Surly Disc Trucker, Cervelo P2, CoMotion Tandem

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked 2 Times in 2 Posts
Front Derailleur Height

I recently changed from 30-42-52 chainrings to a 28-38-48 chainrings. I swapped out the cranks and adjusted the Derailleur just fine, but I didn't drop the derailleur down, since I would have to re-align and re-clamp the seatpost clamp. What kind of problems can arise from having the derailleur be higher than the 1-2 mm height suggested? In working through the gears there doesn't seem to be any problem shifting. At this point, would you drop it down or leave it be?
DogBoy is offline  
Old 05-06-05, 08:23 AM
  #2  
Senior Member
 
sydney's Avatar
 
Join Date: Jan 2004
Posts: 9,428
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by DogBoy
I recently changed from 30-42-52 chainrings to a 28-38-48 chainrings. I swapped out the cranks and adjusted the Derailleur just fine, but I didn't drop the derailleur down, since I would have to re-align and re-clamp the seatpost clamp. What kind of problems can arise from having the derailleur be higher than the 1-2 mm height suggested? In working through the gears there doesn't seem to be any problem shifting. At this point, would you drop it down or leave it be?
I'm surprised it works well,but if it does, then you really don't have an issue. I'd of just done it right to start with.
sydney is offline  
Old 05-06-05, 08:38 AM
  #3  
Licensed Bike Geek
 
Davet's Avatar
 
Join Date: Oct 2002
Location: Los Barriles, Baja Sur, Mexico
Posts: 1,360

Bikes: Look 585, Kirk Terraplane, Serotta Ottrott, Spectrum Super Custom, Hampsten Carbon Leger Tournesol

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 92 Post(s)
Liked 69 Times in 48 Posts
Originally Posted by DogBoy
I recently changed from 30-42-52 chainrings to a 28-38-48 chainrings. I swapped out the cranks and adjusted the Derailleur just fine, but I didn't drop the derailleur down, since I would have to re-align and re-clamp the seatpost clamp. What kind of problems can arise from having the derailleur be higher than the 1-2 mm height suggested? In working through the gears there doesn't seem to be any problem shifting. At this point, would you drop it down or leave it be?
A strong possibility of overshifting the big ring and throwing your chain off.

It's a simple job and should be done.
Davet is offline  
Old 05-06-05, 08:56 AM
  #4  
No one carries the DogBoy
Thread Starter
 
Join Date: Feb 2004
Location: Upper Midwest USA
Posts: 2,320

Bikes: Roubaix Expert Di2, Jamis Renegade, Surly Disc Trucker, Cervelo P2, CoMotion Tandem

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked 2 Times in 2 Posts
Planned to do it from the start, but when it worked fine after the crank swap thought I might only have to adjust the wire tension. That seemed to work fine, hence the question. I guess I'll adjust it tonight. Thanks.
DogBoy is offline  
Old 05-06-05, 09:15 AM
  #5  
Senior Member
 
Join Date: Jul 2004
Location: Cental New Jersey
Posts: 469

Bikes: Klein Quantum Pro

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Use a torque wrench. Check the ParkTool web site for torque specs so you don't crush anything. Use a penny or a dime as a spacer to get the height correct.
NJWheelBuilder is offline  
Old 05-06-05, 09:20 AM
  #6  
Senior Member
 
sydney's Avatar
 
Join Date: Jan 2004
Posts: 9,428
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by NJWheelBuilder
Use a torque wrench. Check the ParkTool web site for torque specs so you don't crush anything.
Gimmie a break!....Altho I did hear of a ham fisted moron hack that hosed a seattube on an CF calfee. But,all really it takes is a bit of common sense.
sydney is offline  
Old 05-06-05, 09:59 AM
  #7  
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Posts: 30,225

Bikes: Catrike 559 I own some others but they don't get ridden very much.

Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 1572 Post(s)
Liked 643 Times in 364 Posts
Originally Posted by DogBoy
Planned to do it from the start, but when it worked fine after the crank swap thought I might only have to adjust the wire tension. That seemed to work fine, hence the question. I guess I'll adjust it tonight. Thanks.
If you feel that it's working fine now, what do you hope to gain by changeing it? If it ain't broke, why do you want to fix it?
Retro Grouch is offline  
Old 05-06-05, 10:00 AM
  #8  
No one carries the DogBoy
Thread Starter
 
Join Date: Feb 2004
Location: Upper Midwest USA
Posts: 2,320

Bikes: Roubaix Expert Di2, Jamis Renegade, Surly Disc Trucker, Cervelo P2, CoMotion Tandem

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Liked 2 Times in 2 Posts
How about I assume the current clamp is at the appropriate tension, and count the number of revolutions needed to "free" the clamp for movement, then tighten with the same number of revolutions. Or I can just tighten to "snug."
DogBoy is offline  
Old 05-06-05, 10:08 AM
  #9  
Senior Member
 
sydney's Avatar
 
Join Date: Jan 2004
Posts: 9,428
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by DogBoy
How about I assume the current clamp is at the appropriate tension, and count the number of revolutions needed to "free" the clamp for movement, then tighten with the same number of revolutions. Or I can just tighten to "snug."
Honestly, it you don't know how to tighten a derailer clamp by feel,should you really be working on bikes? The same senario applies to tightening the cable clamp. The ARs would grab their US Bureau of Standards calibrated torque wrench. All others would just grab the seat of their pants and a hex wrench.
sydney is offline  
Old 05-06-05, 10:36 AM
  #10  
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Posts: 30,225

Bikes: Catrike 559 I own some others but they don't get ridden very much.

Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 1572 Post(s)
Liked 643 Times in 364 Posts
Originally Posted by DogBoy
How about I assume the current clamp is at the appropriate tension, and count the number of revolutions needed to "free" the clamp for movement, then tighten with the same number of revolutions. Or I can just tighten to "snug."
"Snug" will be fine. I'm a believer in using torque wrenches, but I only use them for cranks and bottom brackets, which I think that most people under torque; and high dollar stems, which I think that most people over torque. A bigger problem with things like front derailleur clamps and the like is using worn out allen wrenches which can round out the bolts.
Retro Grouch is offline  
Old 05-06-05, 10:43 AM
  #11  
Senior Member
 
Join Date: Jul 2004
Location: Cental New Jersey
Posts: 469

Bikes: Klein Quantum Pro

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
People do it all the time. You can do whatever you want without one. Its your bike. I always use a torque wrench.
NJWheelBuilder is offline  
Old 05-06-05, 10:46 AM
  #12  
Senior Member
 
Join Date: Jul 2004
Location: Cental New Jersey
Posts: 469

Bikes: Klein Quantum Pro

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Do it the right way. Use a torque wrench. That whole "feel" thing is nonsense. One persons "feel" is different from another persons "feel."
NJWheelBuilder is offline  
Old 05-06-05, 02:36 PM
  #13  
Senior Member
 
sydney's Avatar
 
Join Date: Jan 2004
Posts: 9,428
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by NJWheelBuilder
Do it the right way. Use a torque wrench. That whole "feel" thing is nonsense. One persons "feel" is different from another persons "feel."
You are the one blowing the nonsense.
sydney is offline  
Old 05-06-05, 03:59 PM
  #14  
NFL Owner
 
monogodo's Avatar
 
Join Date: Sep 2004
Location: Irving Heritage District
Posts: 1,496

Bikes: 7-Eleven Eddy Merckx, Vitus Futural, Catamount FRS, Colnago SL, SS MTB

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Liked 14 Times in 9 Posts
Originally Posted by sydney
You are the one blowing the nonsense.
Wrong.

What one person feels is tight, another would consider loose, and a third would not be able to budge. Everyone has different hand strength. Everyone has different levels of control on how tightly they turn a wrench.

I don't use a torque wrench. I wrench by feel. Every bike I have ever worked on, I did so as if I were going to be the one riding it. If I ever have an issue with a part that I installed coming loose because of improper tightness, I'll invest in a torque wrench.
monogodo is offline  
Old 05-06-05, 04:18 PM
  #15  
Senior Member
 
sydney's Avatar
 
Join Date: Jan 2004
Posts: 9,428
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by monogodo
Wrong.

What one person feels is tight, another would consider loose, and a third would not be able to budge. Everyone has different hand strength. Everyone has different levels of control on how tightly they turn a wrench.

I don't use a torque wrench. I wrench by feel. Every bike I have ever worked on, I did so as if I were going to be the one riding it. If I ever have an issue with a part that I installed coming loose because of improper tightness, I'll invest in a torque wrench.
.....The comment about nonsense was directed at the 'have to have torque wrench' nonsense....Certainly, everyone has a different sense of feel. But one developes their own correct sense of it. That's part of what the brain is for, unless you were born with a torque wrench in cranium instead of one.
sydney is offline  
Old 05-07-05, 06:22 PM
  #16  
Senior Member
 
Join Date: Jul 2004
Location: Cental New Jersey
Posts: 469

Bikes: Klein Quantum Pro

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
So you are saying that you can adjust a bolt to the manufacturers recommended torque just by "feel?" You are saying that actually measuring the torque is not as good as guessing? That's truly amazing.
NJWheelBuilder is offline  
Old 05-07-05, 06:36 PM
  #17  
Senior Member
 
sydney's Avatar
 
Join Date: Jan 2004
Posts: 9,428
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by NJWheelBuilder
So you are saying that you can adjust a bolt to the manufacturers recommended torque just by "feel?" You are saying that actually measuring the torque is not as good as guessing? That's truly amazing.
I like chocolate....you must be a vanilla person.Whatever..........but I don't think the ones that forego a troque wrench are stupid or hacks. Read what moonogodo has to say in an immediate preceding post.
sydney is offline  
Old 05-07-05, 07:48 PM
  #18  
The Red Lantern
 
Rev.Chuck's Avatar
 
Join Date: Apr 2003
Location: Raleigh NC
Posts: 5,965
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
If you do it enough you do get the calibrated elbow. I use a torque wrench for a lot of things, like the new two piece cranks and stem clamps but not the pinch bolt on the der clamp. However a newb or a person that does not know their own strength might be better off using one to make sure. This also assumes the wrench is calibrated correctly.
__________________
Are you a registered member? Why not? click here to register. Its free, and only takes 27 seconds!
Help out the forums, abide by our community guidelines.

I am in the woods and I have gone crazy.
Rev.Chuck 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.