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Noise & Vibration When in High Gear

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  • July 28, 2016 at 10:27 am #26072
    perky416

    Hi guys,

    First post here, im looking for a bit of advice is possible.

     

    Yesterday I was adjusting my gears and I noticed I am getting a droaning sound, a metal on metal rub sound once or twice per rotation and i can feel vibration through the pedals when in the highest couple of gears, I have also noticed it when riding.

     

    A bit of research on google pointed me to a worn chain. I purchased the bike a litte over a year ago and rode maybe a couple of hundred miles last summer, this summer since I got it out again I have ridden maybe 50 miles, seems way too soon to be getting a worn chain.

    When inspecting my bike I have noticed the following things of concern:

    • On the outer edge of the highest gear on the cassette, there is a couple of mm gap between 1 tooth and the end of the casette as a pose to it being flush against each other as with all other teeth, along with what appears to be a radial mark where metal has been scraped away between the tooth and the next one to the left. Also the tooth in question is slightly closer to the next gear down than the rest of the teeth. It would be better to show a picture however being new to this forum I cant seem to figure out how to do it. Could this be causing me any problems?

     

    • When looking at the cassette from above, when in the highest gear there is naturally a gap between the chain and the next gear down towards the rear of the bike where the chain leaves to go to the rear derailleur, however at the front of the casette where the chain leaves to go to the crankset, there is no gap and the chain appears to be rubbing against the next gear down. This is when in the highest gear on the crankset so the chain isnt at its extremes. Is this normal or should the chain not be rubbing on the next gear down at all?

     

    • There are some teeth shorter than others on the crankset. Is this normal or do I have a problem here?

    As an engineer these things dont seem right to me, however being new to cycling I thought it best to put these things out there to you more experianced people.

     

    If the above is not of any concern what do you think could be causing the noise and vibrating?

     

    All help greatly appreciated.

    Many Thanks

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Viewing 15 replies - 1 through 15 (of 16 total)
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  • July 29, 2016 at 6:38 pm #875701
    0
    BBB

    Take it to a bike shop.

    Take it to a bike shop.

    July 28, 2016 at 10:58 pm #875699
    0
    Jack Osbourne snr

    Very very difficult to tell
    Very very difficult to tell without being able to look, see and feel…

    However…Is the rear wheel properly centred in the dropouts?

    Sounds a bit like very light disc brake rub. Put the bike on the floor, open up the qr, check the alignment of the wheel and retighten QR.

    Also, the hub does sound as if it has a slight rumble which, as its a Boardman, is a common feature of the Formula hubs used in the OE wheels.

    July 28, 2016 at 5:03 pm #875697
    0
    perky416
    That is an amazingly clean cassette and chain.   Lack of lube?

    Chain casette and crank cleaned and lubed just yesterday, its muc off hydro dynamic, a really light blue thats doesnt really show up in the pictures.

     

    the rubbing in picture 2 is inevitable because not all the sprockets can be lined up with the chainrings. It’s nothing to worry about. The chain will rub smoothly when pedaling forwards as the rear mech guides it into position. When pedaling backwards, the chain will try to jump into the next sprocket because there chainline isn’t perfect. I’d put some fresh lube on the chain and not worry about it. All my bikes make some noise in the workstand, and I’d be amazed if you could feel it over road vibrations when riding

    Explains it perfectly! I found this whilst trying to investigate vibrations through the pedals when riding in a high gear, I wondered if it would be a contributing factor, the search continues lol.

     

    And none of the above really explains a droning sound or vibration through the pedals….

    Yep is has me stumped, i have been over under and around my bike trying to pinpoint where it is coming from but sadly still no luck 🙁

    July 28, 2016 at 5:00 pm #875695
    0
    Dnnnnnn
    perky416 wrote:
    I thought i would take a quick vid and upload it:

    https://www.youtube.com/watch?v=1XhTa83P_cQ

    You can hear the rattle of the chain and ratchet, however at around 16 seconds you can hear another wuring sound in the background and the vibration is felt through the pedals. Its hard to demonstrate even in the video.

    There is no contact what so ever between the chain and anything that there shouldnt be, been all around it and the only thing I can find is the previously mentioned point in my original post on the rear cassette.

    I may just live with it, hopefully I will be picking up a new bike soon so I can compare the 2.

    Thanks again, appreciate it.

    The rumbling sound doesn’t sound metal scraping badly on metal. It sounds a bit like dry bearings (wheel or bottom bracket – I know the sound ‘cos mine are!), or maybe even some kind of wind thing with the mudguards. And you chain does look a bit dry (although it might just be well-and-sparingly lubed).

    July 28, 2016 at 4:34 pm #875693
    0
    Dnnnnnn

    I’d concur with Dave’s points

    I’d concur with Dave’s points – pics 1 and 3 look fine. 

    Re: bullet 2 about chainline. It does look a bit as if the chain is leaving the sprocket at too much of an angle. It looks like it would be heading towards an inner (smaller) chainring – but you said that’s it going from smallest sprocket to outer (largest) chainring…

    If the chain is bobbing when you backpedal but not when you pedal forwards, it’s possible that the rear derailleur is slightly misaligned. That’s often more apparent when backpedalling. If it’s only happening in the smallest sprocket it could be that the ‘H’ (high) limit/stop screw is a screwed in a fraction too far, or the gear cable is a little too tight (although that would probably affect shifting on other sprockets), or the derailleur/it’s hanger may have gotten damaged/twisted.

    I’m not sure it’s any of those things though as they would tend to affect the chain at the back of the sprocket as much or more than at the front (as you look down on it). But your photo shows the opposite, which tends to suggest the problem is forward of the cassette, rather than below it. 

    And none of the above really explains a droning sound or vibration through the pedals….

     

     

    July 28, 2016 at 4:22 pm #875691
    0
    Acm

    ^ run not rub, haha that

    ^ run not rub, haha that could be confusing!

    July 28, 2016 at 4:21 pm #875689
    0
    Acm

    the rubbing in picture 2 is

    the rubbing in picture 2 is inevitable because not all the sprockets can be lined up with the chainrings. It’s nothing to worry about. The chain will rub smoothly when pedaling forwards as the rear mech guides it into position. When pedaling backwards, the chain will try to jump into the next sprocket because there chainline isn’t perfect. I’d put some fresh lube on the chain and not worry about it. All my bikes make some noise in the workstand, and I’d be amazed if you could feel it over road vibrations when riding

    July 28, 2016 at 4:19 pm #875687
    0
    perky416

    I thought i would take a

    I thought i would take a quick vid and upload it:

    https://www.youtube.com/watch?v=1XhTa83P_cQ

    You can hear the rattle of the chain and ratchet, however at around 16 seconds you can hear another wuring sound in the background and the vibration is felt through the pedals. Its hard to demonstrate even in the video.

    There is no contact what so ever between the chain and anything that there shouldnt be, been all around it and the only thing I can find is the previously mentioned point in my original post on the rear cassette.

    I may just live with it, hopefully I will be picking up a new bike soon so I can compare the 2.

    Thanks again, appreciate it.

    July 28, 2016 at 4:02 pm #875685
    0
    . .

    That is an amazingly clean

    That is an amazingly clean cassette and chain.   Lack of lube?

    July 28, 2016 at 3:31 pm #875683
    0
    DaveE128

    Wouldn’t worry too much about

    Wouldn’t worry too much about the rubbing at the cassette if no noise when pedalling forward then.

    Look for contact between the front mech cage and the chain. There should just be clearance in all gears, ideally, but you may have to use the trim function of the shifters to avoid it in some gears.

    July 28, 2016 at 2:48 pm #875681
    0
    perky416

    Hi Dave,

    Hi Dave,

    Thanks for the info.

    The chain is a KMC X10 and the cassette is a 10 spd shimano tiagra 12-30T.

    I have just now got the bike on the stand again, on closer inspection, when cycling the chain backwards you can see it bobbing up and down on the gear that it is rubbing against, however when cycling it forwards it is that close that there is no visible gap however i cant identify any rubbing.

    Also when listening to the droaning noise it appears to be coming from the area of the crankset, however it disspaears and cycles perfectly when taking the chain off.

    Any ideas how I can further diagnose it?

     

    Thanks again.

    July 28, 2016 at 2:31 pm #875679
    0
    DaveE128

    Also, some shimano chains can

    Also, some shimano chains can be put on the wrong way round which might perhaps cause this. See:

    http://brimages.bikeboardmedia.netdna-cdn.com/wp-content/uploads/2012/11/XT-Chain-Mounting-Instructions1.jpg

    July 28, 2016 at 1:46 pm #875677
    0
    DaveE128

    Further thought on 2: how

    Further thought on 2: how many gears do you have in the cassette, and what chain are you using? (it will be written on the chain).

    I wonder if you’re using a chain that’s too wide. Eg an 8 speed chain on 9/10/11 speed cassette.

    July 28, 2016 at 1:42 pm #875675
    0
    DaveE128

    On point 3, The different

    On point 3, The different height teeth on the chain rings is fine. Look at the lowest ring here:

    http://sheldonbrown.com/images/ramps-pins.jpg

    This is one of the features (along with the pins and ramps labelled in the picture) that helps with shifting between gears.

    On point 2, I am struggling to understand what you mean. It sounds very wrong. A picture would help. It doesn’t sound quite like what you said, but if you’re saying that the jockey wheel/pulley on the rear mech is in contact with the cassette through the chain in certain gears, then this is due to incorrect b-tension adjustment, and will cause additional noise. An excessive gap reduces shifting performance. This link will help you with this issue:

    http://www.parktool.com/blog/repair-help/rear-derailleur-adjustment#article-section-4

    Actually, the whole park tool website will be useful in getting your gears set up right.

    On point 1, it is very hard to tell what you mean, but the shape of the teeth does vary, with differing bevels and recessed areas to improve shifting performance. This photo of a new cassette shows how the tooth shape varies from tooth to tooth:

    http://www.hilarystone.com/images/sale%20images/cassettes/HG8-1.jpg

    If your front mech is not quite adjusted right, it could be rubbing on the chain when in the largest and smallest gears in the cassette, sometimes it’s hard to eliminate this completely which is why some shifters have a trim function. This would often cause rubbing a couple of time per crank revolution, as the pedal forces cause slight deflection of the cranks and chainrings.

    edit: thanks for pictures. 1 and 3 look absolutely fine. 2 looks wrong to me, if there is actually rubbing, and could be a chainline issue.

    July 28, 2016 at 1:22 pm #875673
    0
    perky416

    Hi Duncann,

    Hi Duncann,

    When replying I found an upload field, as it only seems to let me upload one pic at a time I have combined pictures off all issue into one, hope it turns out ok. Please find it attached.

    Thanks

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