Advertise on Bikeforums.net



User Tag List

Results 1 to 12 of 12

Thread: Gear questions

  1. #1
    Senior Member
    Join Date
    Feb 2008
    Location
    UK
    Posts
    2,325
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Gear questions

    Hi all,

    Recently my gears have been playing up.

    Now before I go on a number of things I should confess to:
    - my bike is very dirty!
    - my chain is stretched and the gears worn a bit (I left it too long when checking chain wear and now I will need to replace the cassette and chain)!

    So one day my gears started to skip horribly, so when I got home I adjusted the cable until they worked nicely. The next ride was fine, and the shifted worked perfectly. The following ride, however, things started to skip again. I got home, adjusted the cables and the same thing happened on the next two rides.

    My questions are:
    - what can be causing this? Surely the chain cannot be stretching in between rides, and the gears can't be wearing that quickly - so is it cable stretch?
    - if I was to replace the cassette and chain, would I also need to replace the chainrings and the jockey wheels?

    Thanks

    Daven

  2. #2
    Senior Member
    Join Date
    Aug 2005
    Location
    Pittsburgh, PA
    My Bikes
    '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
    Posts
    25,260
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Check to be sure the cables are clamped securely. If they are slipping in the pinch bolts the shifting will go out of time. Unless your chain is very badly "stretched" your chainrings should be ok as will the rear derailleur pulleys.

  3. #3
    Senior Member kv501's Avatar
    Join Date
    Oct 2011
    Posts
    709
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Adjusting your RD won't do anything for the skipping.

    You need to change your cassette and chain anyway; do that, and if you are still having problems come back and get help. With all of the adjusting you are doing now, start over from from scratch after you've installed the cassette and chain.

  4. #4
    Senior Member
    Join Date
    Sep 2010
    Posts
    2,583
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Fix what you know is wrong (cassette and chain) before you go farther with troubleshooting. While you have things apart check the condition of your cables and housings and be sure that the housings are properly prepared and installed; ends cut cleanly and filed flat, and the proper ferrules installed. Pay particular attention to the lower loop of housing going into your derailleur; it tends to collect dirt and crud. Dirty or poorly-installed cables and housings are a frequent cause of shifting woes.

  5. #5
    Senior Member
    Join Date
    Feb 2008
    Location
    UK
    Posts
    2,325
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by HillRider View Post
    Check to be sure the cables are clamped securely. If they are slipping in the pinch bolts the shifting will go out of time. Unless your chain is very badly "stretched" your chainrings should be ok as will the rear derailleur pulleys.
    Forgot to mention, this was one of the first things I checked. How badly stretched is "badly stretched"? I think mine, after a quick measurement with a digital caliper, is 3.216 inches instead of 3 inches, which to me is pretty badly worn! I have been very bad with maintenance this year

    Quote Originally Posted by kv501 View Post
    Adjusting your RD won't do anything for the skipping.

    You need to change your cassette and chain anyway; do that, and if you are still having problems come back and get help. With all of the adjusting you are doing now, start over from from scratch after you've installed the cassette and chain.
    Well to be honest, the skipping just seems to be the derailleur not moving enough to get the chain onto the next cog and the chain skipping between the two. When I adjust the cable then the shifting is perfect with no skipping.

    Quote Originally Posted by dsbrantjr View Post
    Fix what you know is wrong (cassette and chain) before you go farther with troubleshooting. While you have things apart check the condition of your cables and housings and be sure that the housings are properly prepared and installed; ends cut cleanly and filed flat, and the proper ferrules installed. Pay particular attention to the lower loop of housing going into your derailleur; it tends to collect dirt and crud. Dirty or poorly-installed cables and housings are a frequent cause of shifting woes.
    I will check out the cable, was thinking of replacing it anyway. The cable and chain haven't been changed since I bought the bike (about 10,000 miles and 3.5 years ago!) so I was going to get together a shopping list.

    Thanks for the replies,

    Daven

  6. #6
    Senior Member
    Join Date
    Aug 2005
    Location
    Pittsburgh, PA
    My Bikes
    '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
    Posts
    25,260
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by daven1986 View Post
    Forgot to mention, this was one of the first things I checked. How badly stretched is "badly stretched"? I think mine, after a quick measurement with a digital caliper, is 3.216 inches instead of 3 inches, which to me is pretty badly worn! I have been very bad with maintenance this year
    (3.216/3.000)*100 = 7%!! That can't be accurate as the chain would have broken long since. If you are measuring using the inside of the rollers as indexing points, that will give a misleading reading. Use a good ruler and measure the center-to-center distance between two pins that are 24 pins apart (i.e. 12 full links). On a new chain that should be 12.00 inches. If it's 12-1/8" or more (1%) your chain is overdue and the cassette with it.

  7. #7
    Senior Member
    Join Date
    Feb 2008
    Location
    UK
    Posts
    2,325
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by HillRider View Post
    (3.216/3.000)*100 = 7%!! That can't be accurate as the chain would have broken long since. If you are measuring using the inside of the rollers as indexing points, that will give a misleading reading. Use a good ruler and measure the center-to-center distance between two pins that are 24 pins apart (i.e. 12 full links). On a new chain that should be 12.00 inches. If it's 12-1/8" or more (1%) your chain is overdue and the cassette with it.
    ok I will try it again with a ruler! The batteries are on the way out in the caliper so it might (hopefully) be out!!

  8. #8
    coprolite fietsbob's Avatar
    Join Date
    Jun 2010
    Location
    NW,Oregon Coast
    My Bikes
    7
    Posts
    38,912
    Mentioned
    20 Post(s)
    Tagged
    0 Thread(s)
    From the general direction of this , I'd say:new chain and cog set , for sure ..
    freewheel or cassette, depending on what you have on the wheel.

  9. #9
    Senior Member
    Join Date
    Sep 2010
    Posts
    2,583
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    If you buy cables, get decent-quality ones with compressionless lined housings and die-drawn stainless inner wires. There are a number of good ones available, no need to go with anything exotic. Here's a good guide to cable preparation and installation: http://sheldonbrown.com/cables.html Pay close attention to the sections "Cutting Housing and Preparing the Ends" and "Cable Lubrication" lubrication will probably NOT be required with modern cables.

  10. #10
    Senior Member Retro Grouch's Avatar
    Join Date
    Feb 2004
    Location
    St Peters, Missouri
    My Bikes
    Rans Enduro Sport, Hase Kettweisel Tandem, Merin Bear Valley beater bike
    Posts
    23,591
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Check your cable housings.

    Whenever I've encountered a bike that needed frequent cable tension adjustments, the cause was a cable housing that was gradually shortening itself.

    A worn chain on a dirty bike sounds to me like a candidate for some major component replacements.

  11. #11
    Senior Member Bill Kapaun's Avatar
    Join Date
    Feb 2007
    Location
    Mid Willamette Valley, Orygun
    My Bikes
    86 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.
    Posts
    6,768
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    "Now before I go on a number of things I should confess to:
    - my bike is very dirty!"

    I think some cleaning/lubing cables may be in order???

  12. #12
    Senior Member
    Join Date
    Feb 2008
    Location
    UK
    Posts
    2,325
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    If it helps, here are some pictures of my chainrings and cogs - do they look worn, they don't look to bad to me (although the only pictures of worn cogs I've seen are off Sheldon's website). Either way they are disgustingly dirty, and I have a new cassette and chain in the post, so even if I don't need them now, I have them for when I do need them!

    30032012247.jpg

    30032012248.jpg

    Thanks

    Daven

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •