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

Derailleur adjustment, chainring questions

Search
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.

Derailleur adjustment, chainring questions

Thread Tools
 
Search this Thread
 
Old 03-10-01, 04:44 PM
  #1  
Mr. Cellophane
Thread Starter
 
RainmanP's Avatar
 
Join Date: Nov 2000
Location: New Orleans, LA
Posts: 3,037
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
I was just taking my first serious stab at really getting my derailleurs adjusted. Shifting just didn't seem "clean". I used the instructions in the "Bicycling" maintenance issue of a couple of months ago. Ran into some snags, due mostly to my lack of experience, though things seem pretty good. Still have some questions.

Front derailleur - Checked and adjusted inner and outer limits. I think my large chainring may be a little bent. I did have a crash a few months ago. Even as far as the outer limit adjustment will go when the chain is on biggest ring/smallest cog, the chain ticks the derailleur in one area, while the rest of the chainring the chain is 2-3 mm away. I clamped a little stick in place as an indicator to make sure the "wobble" is in the chainring and not just the chain moving around. It does seem to be a section of the ring, not just one bent tooth. So can I straighten this thing. This is a lowend Suntour crankset with riveted rings so I can't just replace the chainring. This is not a burning issue since I seldom use the big ring/small cog combination. Any comments/suggestions would be welcome, though.

Rear derailleur - My lowend rear der does not have a tension adjustment screw, just the clamp bolt. So I couldn't adjust exactly as described. after several attempts that resulted in too tight with not enough loosening adjustment in the adjuster on the grip shift and vice versa, a lot of things worked fine on the workstand but not on the road. Usually, shifting was slick going smaller to larger cogs, but often difficult to get to shift from larger to smaller. I finally got pretty good results as follows. Chain on big ring/small cog. Screw adjuster on grip shift all the way in. Back off 30 clicks (about three full turns). Loosen cable clamp bolt on der. Take up slack and tighten clamp bolt. Go for a ride. Move shifter from 1 to 2 (no shift). Turn adjuster in until shift occurs. Tweak until shifts are as smooth as possible. This required taking up 29 of the 30 aforementioned clicks. Shifting seems pretty good, about as smoother or slightly smoother that it has ever been, though I am still not totally thrilled. Sigh. I guess you can't get those Campy snick, snick shifts out of lowend parts. Anyway, does this approach seem reasonable? Suggestions for smoother shifts, short of new derailleur, shifter, etc.? Oh, new bike, pretty well maintained, just over 1000 miles. Wear probably not an issue. Shifting has never been anything but adequate. SRAM 5.0 derailleur, SRAM Grip Shift, Shimano HG cassette, chain unknown, maybe SRAM. Each link has what appears to be a Z in it. Again, any comments/suggestions would be appreciated.
Regards,
Raymond
RainmanP is offline  
Old 03-10-01, 05:58 PM
  #2  
NOT a weight weenie
 
Hunter's Avatar
 
Join Date: Dec 2000
Posts: 1,762
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Rainman you can use Klein pliers (not from the bike manufacturer it is a type) or an sturdy adjustable wrench and bend the front chainring back into shape. As far as the r. der. well the only thing I can tell you is this. Turn the barrel adjuster on the shifter all the way in then back out about a half a turn. Take up any cable slack. You need at this point to check the limit screws on the r. der. make sure that you have a straight line from the upper pulley to the lower pulley from your cogs(gears). You will use the H screw for this. If it leans to the right then push the screw in in 1/4 turn increments. If it leans to the left then back the screw out in 1/4 turn invcrements. Now go the large cog in the rear. Do the same for this gear. You will use the L screw. Once this is done take up any slack with the barrel adjuster and go through the gears. Thre are times in which a bike in a stand will shift differently then on the road or dirt. If this does not make you happy then check your der. hanger and make sure it is straight. If not and it is replaceable then get a new one. If you do not have one and it is a steel frame then you can try to make it straight but I reccomend a trip to your LBS for this project.
Have Fun!
Hunter is offline  
Old 03-11-01, 03:44 PM
  #3  
Mr. Cellophane
Thread Starter
 
RainmanP's Avatar
 
Join Date: Nov 2000
Location: New Orleans, LA
Posts: 3,037
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Hunter,
Thanks for the note. I have quite a few types of pliers, but I am not familiar with Klein. May have to pull out the MSC catalog. Is a Klein like a large lineman plier? I have a pretty large Cresent wrench. Is that a possible alternative for straightening the chainring?

Following the "Bicycling" procedure I check the H and L limits first. They looked right on. The shifting is not bad. In fact, I think it is probably as good as this particular component setup will get, quick and reasonably smooth. What I probably should do is ride a bike with really good, well-adjusted components to see what the ideal feels like. I may just have an overly optimistic vision of what good shifting should be. 'Course, on the other hand, if I road a full Campy Record setup around the block, I might never want to get on my bike again. Maybe I should be careful.
Regards,
Raymond
RainmanP is offline  
Old 03-11-01, 04:30 PM
  #4  
NOT a weight weenie
 
Hunter's Avatar
 
Join Date: Dec 2000
Posts: 1,762
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Yes you are correct about the pliers. I also agree with yo about the shifting opinion. For the money we as cyclists shell out for parts it would seem that they would just work. I still am using XT and Suntour XC PRO thumbies and Suntour XC PRO der.'s. It is just my opinion after years of riding a whole slew of sstuff and trying most everything I could get my hands on that most of it was crap. There are some manufacturerers that build stuff that just simply works. not fancy not flashy all anondized and powder coated, but it just works. That should not be to hard to ask for when spending $1000 on a good quality MTB or Road bike for that it should just work no hassles, no problems, just work. I mean lets be realistic it does not cost shimaNO alot of money to make their stuff. You know how much it costs to make a Rock Shox like the SID? About $8 that is it, and how much do they cost? Around what?? $250-$300!!!!!!!!! How much for a Manitou.........about $5!!! They are mass produced on a machine!!!!!!!!! It is like everything else how much for toothpaste? About $. 05 and how much for Nike Air Jordan's about $5-10!! So make these people rich work hard WORK REAL HARD spend your money and get hassle's!!
Hunter is offline  
Old 03-11-01, 08:37 PM
  #5  
Senior Mem. & Trail Sage
 
steve33's Avatar
 
Join Date: Dec 2000
Location: Asheville NC
Posts: 130
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Rainman. im not even going to get into this one.
There are static ajustements on your der`s, that must be made before the dynamic ajustements, since clik shifting came out ajustment is a whole diffrent worldThe inter net is like my son telling me sompthing about computers, i will mess it up every time.
Go to a bike mechanic please.!!!!

(ps. as an xe mechanic i know from whence i speak)
steve33 is offline  
Old 04-05-01, 10:27 PM
  #6  
Senior Member
 
mike's Avatar
 
Join Date: Jul 2000
Location: Snowy midwest
Posts: 5,391
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Raymond:

I read your problem. Check one simple thing.

Check to make sure you don't have a sticky spot in your chain. A bad chain can make you think you have trouble somewere else.

If your front sprocket was bent, the chain would likely come off with every revolution and you wouldn't likely notice it in the back end.

You might find that you have a link or two that is not flexing freely. If so, try bending the links by grabbing the chain on both sides and bending the chain back and forth sideways - like you are going to break the chain.

Cleaning the chain SOMETIMES works, but usually not for such a problem.

As a last resort, you can replace chain links or the whole chain.
mike is offline  
Old 04-06-01, 12:07 PM
  #7  
Senior Member
 
pat5319's Avatar
 
Join Date: Sep 2000
Location: Spokane WA
Posts: 1,148

Bikes: Seven Axiom Ti, Trek 620, Masi cylocross (steel). Masi Souleville 8spd, Fat Chance Mtn. (steel), Schwinn Triple Bar cruiser, Mazi Speciale Fix/single, Schwinn Typhoon

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Rainman,
For the front chain ring the pliers suggested are probably like a "Model T" wrench, similar to a "monkey"/pipe wrench, with no teeth on the jaws and the jaws are perpendicular to the handle. They came as original equipment with Model T cars and can be found in junk shops and pawn shops. They're very handy for straightening stuff. If the bent part aligns with a spider arm the arm itself may be bent, the "model t wrench works great on arms. You can get a special tool designed for bending chain rings, sometimes a small crescent wrench will work too. Just line up your derailleur plate with the ring and use it as a guide.

As for the rear, I can't offer much that hasn't been said-check to make sure your pulley wheels are parallel with with the plane of your wheel, if they aren't , you may have a bent pully cage or bent dropout. This can mess up shifting and is very, very often a problem, the cage/drop-out can be bent just by laying the bike "peanut-butter side" down.
pat5319 is offline  
Old 04-10-01, 07:30 PM
  #8  
Mr. Cellophane
Thread Starter
 
RainmanP's Avatar
 
Join Date: Nov 2000
Location: New Orleans, LA
Posts: 3,037
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Actually, Pat, since I posted my original message I have gone ahead and replaced the crank and bb with 105. The suspicion of a bent chainring was all I needed to justify the "repair" in my own mind. And from there, the logical thing to do, again in my own mind, was to bite the bullet, spring for 105 STI levers and a drop bar and complete 9 speed upgrade and the transformation of my bike into a machine I will be happy to ride for years.
As you can see, my idea of logic may be suspect, but it works for me. Fortunately, or perhaps unfortunately, I had a little extra cash to play with. I mean what else should I spend it on? Car insurance or something?
Thanks,
Raymond
__________________
If it ain't broke, mess with it anyway!

Last edited by RainmanP; 04-10-01 at 07:32 PM.
RainmanP is offline  
Old 04-11-01, 08:31 AM
  #9  
0^0
 
fubar5's Avatar
 
Join Date: Feb 2001
Location: Rolla, MO
Posts: 4,056

Bikes: Redline Monocog,Surly Crosscheck, Lemond Reno

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Rainman
I ran into the same thing where it works fine on the stand, but not when you get weight on it.
When I adjusted my front deraileur I tried adjust it with the screw for hour, but it still hit the chain when I had it on the outter chainring. So I started looking at the der. more closely and I notice that the adjusting screw won't manipulate the position of the der after a certain point. What you have to do is tighten the shifter CABLE, and that will cause the der. to move away from the bike and stop hitting the chainring. It doesn't really take much of an adustment either.
fubar5 is offline  
Old 04-11-01, 08:33 AM
  #10  
0^0
 
fubar5's Avatar
 
Join Date: Feb 2001
Location: Rolla, MO
Posts: 4,056

Bikes: Redline Monocog,Surly Crosscheck, Lemond Reno

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
excuse my poor typing skills please. I Ment I tried adjusting the der. with the tension *screws for *hours.
fubar5 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



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.