A Cycling & bikes forum. CycleBanter.com

Go Back   Home » CycleBanter.com forum » rec.bicycles » Techniques
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Front cracking noise



 
 
Thread Tools Display Modes
  #1  
Old February 12th 19, 03:40 PM posted to rec.bicycles.tech
Frank Krygowski[_2_]
external usenet poster
 
Posts: 7,104
Default Front cracking noise

On Tuesday, February 12, 2019 at 5:43:08 AM UTC-5, Tanguy Ortolo wrote:
Hello all,

For a few days, I have noticed a new cracking noise that seems to come
from the front of my bicycle. It only starts when I am riding at more
than 25 km/h, and it is the same no matter how bumpy or smooth the
ground is.

I have already experienced cracking sounds from the handlebar in the
past, but it does not come from it in this case, as it continues even if
I release the handlebar and ride without the hands.

The fact that it is related to speed makes me wonder if it could not
come from the front hub ball bearings, what do you think? This is a
Shimano hub dynamo, do you know if its balls can be replaced?


I don't know how easy it is to inspect bearings on a
Shimano dynamo hub, but I'd be very reluctant to try
opening the hub until I'd eliminated all other
possibilities. My guess is that your noise originates
elsewhere.

Things I might check are wheel reflectors, if you have
any installed. They can rattle against spokes in strange
ways. Check fenders, if you have them; check each
attachment point, and also check that the fender is not
slightly touching the tire. Check any bags or baggage on
your bike. (I've had mysterious noises come from items
rattling in my handlebar bag or saddlebag.) Check
attachment points for all accessories - water bottles
and their cages, racks on the bike, lights, bells, etc.

I'd also advise re-checking the tightness of your axle
nuts or quick releases, your headset, handlebars, stem,
etc. even though it sounds like your problem is
elsewhere. And I'd lightly grease the stem and bar
attachment points.

Good luck. It can be devilishly difficult to track down
an intermittent noise.

- Frank Krygowski

Ads
  #2  
Old February 13th 19, 10:27 AM posted to rec.bicycles.tech
Tanguy Ortolo
external usenet poster
 
Posts: 45
Default Front cracking noise

Frank Krygowski, 2019-02-12 15:40+0100:
I don't know how easy it is to inspect bearings on a
Shimano dynamo hub, but I'd be very reluctant to try
opening the hub until I'd eliminated all other
possibilities. My guess is that your noise originates
elsewhere.


I am starting to think so, and I hope so, because it looks like I would
not be able to service the hub, at least not expecting it to work
afterwards.

Things I might check are wheel reflectors, if you have
any installed. They can rattle against spokes in strange
ways. Check fenders, if you have them; check each
attachment point, and also check that the fender is not
slightly touching the tire. Check any bags or baggage on
your bike. (I've had mysterious noises come from items
rattling in my handlebar bag or saddlebag.) Check
attachment points for all accessories - water bottles
and their cages, racks on the bike, lights, bells, etc.

I'd also advise re-checking the tightness of your axle
nuts or quick releases, your headset, handlebars, stem,
etc. even though it sounds like your problem is
elsewhere. And I'd lightly grease the stem and bar
attachment points.


Will do. I already checked part of these, but checking everything and
greasing attachment points cannot harm. I may even detect some other
problems. :-)

Good luck. It can be devilishly difficult to track down
an intermittent noise.


Yes, quite so, but I like the challenge!

--
Tanguy
  #3  
Old February 13th 19, 01:56 PM posted to rec.bicycles.tech
Tanguy Ortolo
external usenet poster
 
Posts: 45
Default Front cracking noise

Last update, I tested it with the bike upside down, so the wheel was
completely unloaded. Reflectors removed, spokes tested and re-tensionned.

The noise is:

* coming from the front wheel;
* present only whith a sufficient rotational speed;
* cracking or sharp clicking, I cannot tell that apart;
* non-cyclic.

Even when it does not make that sound, the hub seems to be making some
low scratching noise.

I still have to try riding with another front wheel, but I have now
eliminated anything that is not at or near the front wheel. The noice
certainly does not come from the frame, pedals, transmission, and
probably not from the handlebar or headset.

If the try with another wheel confirms it comes from the wheel, I will
have a look at the hub bearings on the non-drive side, which appear to
be easy to take apart, and I will eventually open the other side as
well, even if there is a chance that I break it: if the hub is worn out,
the worst that can happen anyway is that I have to buy another one.

--
Tanguy
  #4  
Old February 13th 19, 03:48 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 899
Default Front cracking noise

On Wednesday, February 13, 2019 at 4:56:57 AM UTC-8, Tanguy Ortolo wrote:
Last update, I tested it with the bike upside down, so the wheel was
completely unloaded. Reflectors removed, spokes tested and re-tensionned.

The noise is:

* coming from the front wheel;
* present only whith a sufficient rotational speed;
* cracking or sharp clicking, I cannot tell that apart;
* non-cyclic.

Even when it does not make that sound, the hub seems to be making some
low scratching noise.

I still have to try riding with another front wheel, but I have now
eliminated anything that is not at or near the front wheel. The noice
certainly does not come from the frame, pedals, transmission, and
probably not from the handlebar or headset.

If the try with another wheel confirms it comes from the wheel, I will
have a look at the hub bearings on the non-drive side, which appear to
be easy to take apart, and I will eventually open the other side as
well, even if there is a chance that I break it: if the hub is worn out,
the worst that can happen anyway is that I have to buy another one.

--
Tanguy


If that is the sort of hub with free bearings I would suggest that it is a broken ball. This will destroy the race in short order.
  #5  
Old February 13th 19, 10:49 PM posted to rec.bicycles.tech
Tanguy Ortolo
external usenet poster
 
Posts: 45
Default Front cracking noise

Well in fact, I will not need to try with another wheel. As I was riding
home, the noise kept increasing, and at some point, my front wheel
started to slow me with a drag similar to slightly pulling on the
brakes.

That definetely comes from the front hub. When turned, the wheel slow
down to a halt in less than one second, even with the brakes wide open,
and while nothing is making any noise that would suggest a friction from
somewhere else.

I will try to service the dynamo hub, before considering buying a new
one.

Thank for all the advice!

--
Tanguy
  #6  
Old February 13th 19, 11:00 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 899
Default Front cracking noise

On Wednesday, February 13, 2019 at 1:49:50 PM UTC-8, Tanguy Ortolo wrote:
Well in fact, I will not need to try with another wheel. As I was riding
home, the noise kept increasing, and at some point, my front wheel
started to slow me with a drag similar to slightly pulling on the
brakes.

That definetely comes from the front hub. When turned, the wheel slow
down to a halt in less than one second, even with the brakes wide open,
and while nothing is making any noise that would suggest a friction from
somewhere else.

I will try to service the dynamo hub, before considering buying a new
one.

Thank for all the advice!

--
Tanguy


I haven't seen a dyno-hub in forever. So perhaps the newer ones have sealed bearings and that would make it easy to repair. I'm sure that you could find the service manual on-line.
  #7  
Old February 13th 19, 11:01 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 899
Default Front cracking noise

On Wednesday, February 13, 2019 at 2:00:04 PM UTC-8, wrote:
On Wednesday, February 13, 2019 at 1:49:50 PM UTC-8, Tanguy Ortolo wrote:
Well in fact, I will not need to try with another wheel. As I was riding
home, the noise kept increasing, and at some point, my front wheel
started to slow me with a drag similar to slightly pulling on the
brakes.

That definetely comes from the front hub. When turned, the wheel slow
down to a halt in less than one second, even with the brakes wide open,
and while nothing is making any noise that would suggest a friction from
somewhere else.

I will try to service the dynamo hub, before considering buying a new
one.

Thank for all the advice!

--
Tanguy


I haven't seen a dyno-hub in forever. So perhaps the newer ones have sealed bearings and that would make it easy to repair. I'm sure that you could find the service manual on-line.


Come to think of it, it sounds more like a broken axle.
  #9  
Old February 14th 19, 12:26 AM posted to rec.bicycles.tech
Frank Krygowski[_4_]
external usenet poster
 
Posts: 6,687
Default Front cracking noise

On 2/13/2019 4:49 PM, Tanguy Ortolo wrote:
Well in fact, I will not need to try with another wheel. As I was riding
home, the noise kept increasing, and at some point, my front wheel
started to slow me with a drag similar to slightly pulling on the
brakes.

That definetely comes from the front hub. When turned, the wheel slow
down to a halt in less than one second, even with the brakes wide open,
and while nothing is making any noise that would suggest a friction from
somewhere else.

I will try to service the dynamo hub, before considering buying a new
one.

Thank for all the advice!


Please keep us posted on how it goes. I've opened and worked on an
ancient Sturmey-Archer Dynohub, but never a Shimano dynamo hub. I'll be
curious what you find.

--
- Frank Krygowski
  #10  
Old February 14th 19, 01:27 AM posted to rec.bicycles.tech
Steve Weeks
external usenet poster
 
Posts: 16
Default Front cracking noise

On Wednesday, February 13, 2019 at 3:49:50 PM UTC-6, Tanguy Ortolo wrote:
Well in fact, I will not need to try with another wheel. As I was riding
home, the noise kept increasing, and at some point, my front wheel
started to slow me with a drag similar to slightly pulling on the
brakes.


That's how my first dynohub failure presented itself. With the wheel off the ground, it wouldn't even spin a full revolution because of the friction in the bearings. If you look at the link I posted before, you will see a step-by-step account of the repair of a dynohub. It may be that the hub I repaired is similar enough to yours that you can figure it out. The "Joule I" hub and the Shimano hub may both be made by Sanyo, in which case some similarity is likely. The Joule I hub has two sealed cartridge bearings; the Shimano hub looks like it has one cartridge bearing on the output side and a cup-and-cone bearing on the non-output side.
You will need soldering equipment, but I doubt there is any aluminum wire to deal with.
If you are careful, you may be able to expose the solder joint by carefully prying the superficial parts off (see the link!). I initially did not do this, and broke the output wire and had to splice it (also described in the link).
Good luck!
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Front cracking noise Zen Cycle Techniques 1 February 13th 19 10:25 AM
Mavic Equipe front wheel bearing noise [email protected] Techniques 19 November 23rd 13 06:17 PM
Cracking Noise from Headset Area ItsFred Techniques 9 October 9th 09 01:35 PM
Rim cracking solution [email protected] Techniques 2 June 7th 09 03:31 AM
Front Derailleur noise when cross-chained - Normal? Flybane Techniques 1 August 19th 06 09:53 PM


All times are GMT +1. The time now is 07:49 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright 2004-2019 CycleBanter.com.
The comments are property of their posters.