Results 1 to 14 of 14
  1. #1
    RoadBikeReview Member
    Reputation:
    Join Date
    May 2014
    Posts
    86

    Diagnosis help please

    Hi, I have a worrying squeal which has developed on my commuter bike. It makes a loud squeal when the bike is rolled backwards, but not at any other time...

    The bike is a Felt QX alloy frame, with Tiagra 4600 Cranks and BB attached. The sound seems to come from the BB area, although I know this can be misleading. Any help appreciated

  2. #2
    Matnlely Dregaend
    Reputation: DrSmile's Avatar
    Join Date
    Jul 2006
    Posts
    4,626
    Tell the pig to start pedaling!

    I would take the chain off and spin the rear wheel and the crank backwards to isolate the noise. Then I'd spin the cassette on the wheel.
    “Bicycling has done more to emancipate women than anything else in the world.” - Susan B. Anthony 1896
    "Cycling and ethical bankruptcy have always gone together." - Bike Snob NYC
    "White personifies this generation's obsession with superficiality, one in which a carefully curated social media post is more important than the actual ride" - Daimeon Shanks
    "I haven't %^&* like that since I was an altar boy" Hank Moody

  3. #3
    RoadBikeReview Member
    Reputation:
    Join Date
    May 2014
    Posts
    86
    Thanks, sounds like good advice. I need daylight so I won't try until the weekend...

  4. #4
    RoadBikeReview Member
    Reputation:
    Join Date
    Mar 2015
    Posts
    135
    My gut is telling me to look at the brakes. I'm guessing one is rubbing oh-so-slightly and moving forward is quiet but moving backwards is against the wear pattern and subsequently making a slight noise, resonated by the frame making it hard to pin-point.

  5. #5
    RoadBikeReview Member
    Reputation:
    Join Date
    May 2014
    Posts
    86
    I thought maybe brakes too, although the noise sounded metallic, like a disc brake (the bike has rim brakes).

    I went to have a good look at the weekend and, guess what... I couldn't replicate the problem! I'll have to wait. Thanks again for replies.

  6. #6
    RoadBikeReview Member
    Reputation:
    Join Date
    May 2014
    Posts
    86
    The noise came back this morning, and ruled out a few things, as it happened whilst rotating the pedal (backward) to start position. So, definitely not brakes and probably crank or FD.

  7. #7
    a real member's member
    Reputation: blackfrancois's Avatar
    Join Date
    Jul 2016
    Posts
    2,738
    Quote Originally Posted by riccardo123 View Post
    It makes a loud squeal when the bike is rolled backwards, but not at any other time...
    patient: doc, it hurts when i do this...

    doctor: don't do that.
    Yossarian: don't worry. nothing's going to happen to you that won't happen to the rest of us.

  8. #8
    RoadBikeReview Member
    Reputation:
    Join Date
    May 2014
    Posts
    86
    Thanks, Doc. I'm sure the walk home will be fun after I don't roll the bike back out of the rack at the train station...

  9. #9
    RoadBikeReview Member
    Reputation:
    Join Date
    Mar 2015
    Posts
    135
    I did have a time when I had a string or maybe hair (it was eventually covered in grease so it was hard to tell) that was wrapped around the crank near the bearings. You might want to see if there's something obvious like that you can clean out. Something that changes tension when rotated backwards that changes applied pressure and subsequently rubs differently causing the squeak.

  10. #10
    is riding in MOPP4
    Reputation: Tachycardic's Avatar
    Join Date
    Mar 2013
    Posts
    684
    Is the chain rubbing against the FD when pedaling backwards?
    Wake me up when it's alarm green.

  11. #11
    RoadBikeReview Member
    Reputation:
    Join Date
    Mar 2017
    Posts
    8
    So, not rolling backwards, but pedalling backwards.

    Somewhere in your drivetrain, or freehub. Don't see how a chain rubbing a front derailleur would make a squeal. That would make a rubbing sound.

    Lubrication? Clean and freshly lubed chain? How about jockey wheels? Squeal doesn't sound like bottom bracket noise. Do you ride this bike in rain and/or snow? Is there salt used where you are?

  12. #12
    is riding in MOPP4
    Reputation: Tachycardic's Avatar
    Join Date
    Mar 2013
    Posts
    684
    Well, he also said that it sounded metallic, so it could be anything. Just trying to exclude the pertinent negatives.
    Wake me up when it's alarm green.

  13. #13
    RoadBikeReview Member
    Reputation:
    Join Date
    Nov 2014
    Posts
    403
    Pedal bearing? Stick another pedal on there and see if it goes away. Odd that it's only one way, but bikes have a way of acting illogically. If it's a squeal and not a creak, it's most likely a bearing somewhere. Anything rubbing on your FD would be obvious.

  14. #14
    RoadBikeReview Member
    Reputation:
    Join Date
    May 2014
    Posts
    86
    ...aaaaand it has vanished again, when I had the time (and daylight) to look into it.

    The initial occurrence (and the worst) was on rolling back, not pedalling. It is easily possible that the cranks were turning when I was rolling back, I didn't check... but that would rule out pedal bearings.

    It is very loud and seems to be resonating in the frame, and also seems to come from the BB area. I am aware that these things can be misleading, but I son't think it's freehub or FD rub.

    The bike is my daily commuter (only short distance, to the train station and back, a couple of steep miles in all weathers). It does get covered in road water and general crap, occasionally including salt. I give it a good clean every 3 weeks or so... maybe not good enough!

    Thanks again for all suggestions.

Similar Threads

  1. Diagnosis appreciated
    By phoehn9111 in forum Components, Wrenching
    Replies: 8
    Last Post: 08-18-2015, 01:33 PM
  2. Need diagnosis...what happened to me?
    By nyvram in forum Coaching
    Replies: 15
    Last Post: 05-08-2011, 03:28 AM
  3. Now there's a diagnosis!
    By Fredke in forum The Lounge
    Replies: 10
    Last Post: 02-18-2011, 01:47 PM
  4. ergopower diagnosis...
    By wankski in forum Campagnolo
    Replies: 7
    Last Post: 07-01-2008, 07:30 PM
  5. Diagnosis please
    By guero in forum Fixed/Single Speed
    Replies: 22
    Last Post: 09-21-2007, 04:42 PM

Posting Permissions

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