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View Full Version : Cracking sound after tune-up! Please help! Am I gonna die??



KLizotte
05-15-2015, 11:23 AM
I got my bike tuned-up in mid-March (new cassette, chain, rings, and rear derailleur cable). I didn't start riding it again till the very end of April. I did put oil in the chain before riding though.

Immediately shifting problems became evident. Skipping and having a hard time upshifting. I brought it back to the LBS and the mechanic said he couldn't find anything wrong with it (to be fair, it was shifting correctly immediately before I got to the LBS). He oiled the chain and told me to come back if the problem returned. Pedaling home I hear weird pinging/cracking sounds for the first time. I stopped a few times but couldn't figure out what was going on. Mysteriously, the sounds disappeared after that evening and I promptly forgot about them.

Unfortunately the shifting problems were still there, including changing gears when I'm just pedaling along. I brought it back to the shop Wednesday night and a different mechanic said the cable was very loose and the H screw needed to be adjusted. Voila, it is now shifting great and feels like normal.

The next day the morning commute was fine. The evening commute was another story. All of a sudden the cracking sounds returned with a vengeance. They sound similar to rocks hitting the the underside of my bike (you know that sound: pinging on aluminum only these have more "crack" to them). Given that these sounds only occur after my shifting problem is looked by the LBS at I'm guessing they are related.

I spent 45 minutes riding around my parking garage trying to pinpoint a pattern or cause to the sounds. They occur whether I'm coasting, pedaling, or shifting, in or out of the seat, under load and not under load, clipped in/not clipped in. I took off my panniers and lights to eliminate those variables as well as checked for any loose bolts. I've moved the seat post around but can't replicate the sound. I've bounced the bike on the pavement to see if anything interesting occurred; it didn't. The sounds sometimes come in succession or sometimes as one offs. The noises are completely random and scary enough that I don't feel super comfortable biking far. Oddly, they seem to occur less frequently the more riding I do so I'm worried the LBS mechanic will ride the bike around the block, not hear anything, then tell me I'm crazy.

Anyone have any ideas what it could be? Could an incorrectly installed cassette cause this problem? A problem with the cable? My receipt says they replaced the cable because it was frayed; I don't know if that is meaningful at all. I never heard these sounds before the tune-up. Is it possible for something to be hitting something inside the frame? I believe my cable is entirely outside the frame though. It sounds like there is a rock inside the frame.

Any advice on what I can tell the mechanic to look at? Or any tests I can carry out before I get to the LBS? Is my frame gonna split in two? This is really ruining my day!!! :mad:

P.S. I'm riding an aluminum Cannondale Synapse 10 speed with a carbon fiber fork, three years old, with handbuilt wheels that were put on a year ago (I don't have the specifics with me).

THANK YOU! :cool:

rcannon100
05-15-2015, 11:32 AM
> They occur whether I'm coasting, pedaling,

Hum, that suggests not bottom bracket

> in or out of the seat

Hum, that suggests not the seat post

Are your wheels true? You make it sound like the sound is irregular. I am concerned that it is your spokes, but your spokes would be very regular. There is nothing sticking into the spokes like the chain going to far in or the derailer?

You say this occurred after full drive train replacement. I am concerned that maybe some of the parts did not match.

How old is the wheel? Can you localize the sound at all? Is it possible that there is a problem with the hub.

There is a GCN video about getting ride of creeks in your bike - and pretty much the advice is - if you cant identify it, take everything apart, clean it, grease it, and put it back together. Phoenix knocked off my mystery creek by greasing my seat post.

KLizotte
05-15-2015, 11:40 AM
The wheels are handbuilt by Bill Mould (Spokes) and only about a year old. I don't think the sounds are coming from the wheels. These are much more of a loud, metallic sound. It's hard to tell, but they sound like they are coming from the bottom bracket area or a little to the back of the bottom bracket. I'm so annoyed because the bike didn't make any noises before I brought it in.

It's odd that the sounds occur under any riding condition. I guess the only common variable is that movement has to be involved (unless I slept through it making noises through the night). Sigh.

paulg
05-15-2015, 11:42 AM
Hate to be a harbinger of doom but it could be a crack in your frame. When the noise occurs "whether I'm coasting, pedaling, or shifting, in or out of the seat, under load and not under load, clipped in/not clipped in." you've eliminated a lot of things with those tests. Have a look at all the joints in the frame to see if you can see anything, sometimes cracks are hard to spot. Turn the bike upside down, and if it's a little dirty (I apologize, if you keep your bike clean:o) ) then cleaning helps with spotting cracks.

Anyway I really hope it's not that, but a cracking sound doesn't sound good. Pinging could be spokes but you said that noise went away.

Good luck

Emm
05-15-2015, 11:50 AM
I'm not going to be able to help you, besides to let you know the same thing (random cracking/hitting noise) happened to me with my last hybrid. It freaked me out. The shop looked at it multiple times, finally doing a full tune up, replacing chain and cassette, cables, checking bottom bracket, pedals, wheels, etc (everything was under warranty), and making sure the frame wasn't cracked. And...no difference. The shifting improved dramatically with the tune up, but the noise kept occurring.

One shop mechanic finally asked me about my rides, which included alot of gravely trails. He theorized gravel got into the frame (possible with how my bike was built--it has some gravel sized holes that the cables go through, and the sound matched), but it still seemed a little far fetched.

I finally sold the stupid bike on cragislist. According to the shop it was 100% safe to ride, so I didn't feel that guilty.

Greenbelt
05-15-2015, 12:02 PM
I had a rock jam up into a shifter pulley recently. Mechanics had never seen that one before. Sadly, I surprise them a lot.

Agree with the suggestion to have the mechanics take if for a test ride. Some things can't be discovered by spinning the bike in a bike stand.

bentbike33
05-15-2015, 03:03 PM
Are you running a Shimano rear hub? Another thing to check is the freehub (i.e., the thing you put the cassette on that clicks when you spin it). I recently was getting odd sounds (not exactly like yours, but my bike is steel) and discovered that the bolt holding the freehub to the body of the rear hub was loose (the rear wheel also had inexplicable play that tightening the cone nuts did not fix). You need a 10mm Allen wrench to tighten it, and will also need to repack your hub bearings afterword.

If none of the above makes sense, go to the LBS.

Simplest way to check this, however, is to swap out the rear wheel if you have another, or if you don't, check for some play in the rear wheel that feels like loose bearings.

ronwalf
05-15-2015, 03:15 PM
The wheels are handbuilt by Bill Mould (Spokes) and only about a year old.

If you have a spare set of wheels (even ones you can borrow from another bike), you should be able to test this relatively easily. If the pings happen while coasting, you don't even need to readjust the derailleur (although you might want to make sure at least one brake works).

KLizotte
05-15-2015, 03:20 PM
All these replies sound ominous. I have the old rear wheel; I'll bring it with me and see what they think about me trying it out for a trial run. I don't have any fancy tools aside from a set of allen wrenches so the LBS has to swap stuff out for me. I strongly suspect the LBS did not install something correctly since these noises only occurred right after my trip to the LBS. Normally this LBS does great work so I'm chalking it up to a fluke.

Jason B
05-15-2015, 04:57 PM
Creeks are a pain. I built up a few bikes and they take are a while to eliminate all of them. This sounds a tad different from the normal creeks, which are simply dealt by tightening and greasing.
A loose cable will cause the chain to skip among other things, which appears to be dealt with. A stuck link will also cause the chain to skip, and may cause a clicking sound if the pin was put in improperly, but this sound happens when you are coasting, which negates the pin theory.
Check you rear derailleur to make sure it not hitting anything. Although improbable, a change in cable tension may have pulled it slightly which may be causing it to hit something. It may be hitting the spokes, or the chain my be too short, causing the RD to hit the cassette, even when coasting.
Make sure it is not hitting the spokes for that can cause epic failure. If it is hitting the cassette, adding a another speed link may be all you need. But with way, check the RD for can get messy, and it will be an easy to see if it is off. Make sure to check the RD in all the gears.
Just my too stinky scents.

dkel
05-15-2015, 05:18 PM
It's possible you have something inside the rim. My son's bike came with a broken spoke nipple, which was immediately evident because of the dangling spoke, but the little bit that had broken off was trapped in the rim, behind the rim tape, and was rattling around in there. Even if you don't have a dangling spoke, it's possible some bit of something got in there, or chipped off of something, and is causing the rattling. You can test it by lifting the bike and spinning the wheel, or even better, take the wheel off and move it around in all directions by hand. If something is in there, you'll have to remove the rim tape to get it out, likely, and it may require a lot of manipulating and gyrating.

That said, it's more likely to be a hub bearing.

KLizotte
05-15-2015, 06:55 PM
Dropped it off at the LBS tonight with the mechanic who saw me a couple of nights ago. He thinks it is probably a problem with the hub bearing. I checked the back wheel for anything loose floating around in the rim as dkel suggested but it was quiet. I also checked the spoke tension unscientifically. Nothing.

If it is the hub, then wow, a loose bearing can be LOUD! I mean really loud.

KLizotte
05-17-2015, 08:59 PM
Well, I took the bike out for an hour today and didn't hear the death rattle. Yah! The LBS replaced two donut shaped thingees (that's a technical term) containing ball bearings in the front hub. I can't believe how loud a bunch of errant ball bearings can be! So a word to the wise, if you have an aluminum frame with a carbon fork and it sounds as if someone is throwing pebbles hard at your frame, get your hubs checked out. And yes, the pings can be very, very loud.

The wheels are only a little over a year old. Am I supposed to get the hubs "serviced" every year? I haven't had anything done to them except this repair.

Thanks for all your help.

dkel
05-17-2015, 09:08 PM
The wheels are only a little over a year old. Am I supposed to get the hubs "serviced" every year? I haven't had anything done to them except this repair.

Cup and cone bearings are not as resistant to the elements as are sealed bearings, so they do need to be repacked with fresh grease periodically. The good news is that they can be serviced and serviced, and end up lasting a long time; the bad news is that if run them too long when in need of servicing, they can ruin the entire hub. Sealed bearings are more expensive, but they resist he elements better; they are either difficult or impossible to service, but they can be replaced, and they will never ruin your hubs, no matter how bad they get. Glad you got the problem fixed!

KLizotte
05-17-2015, 09:59 PM
Cup and cone bearings are not as resistant to the elements as are sealed bearings, so they do need to be repacked with fresh grease periodically. The good news is that they can be serviced and serviced, and end up lasting a long time; the bad news is that if run them too long when in need of servicing, they can ruin the entire hub. Sealed bearings are more expensive, but they resist he elements better; they are either difficult or impossible to service, but they can be replaced, and they will never ruin your hubs, no matter how bad they get. Glad you got the problem fixed!

I learned a lot from this post. So, next year when I bring my bike in for a tune-up I should ask for the hubs to be greased and repacked? I wasn't aware that not doing this could ruin the hubs. Ouch. Also, next time I buy new hubs/wheels I'll ask if they are sealed or not.

I forgot to note in my previous post that the sound did not seem like it was coming from the front. Bike acoustics defy all laws of physics if you ask me. Total cost of repair was $32 with WABA discount.

peterw_diy
05-17-2015, 10:54 PM
So, next year when I bring my bike in for a tune-up I should ask for the hubs to be greased and repacked? I wasn't aware that not doing this could ruin the hubs.
Every year? That depends on several factors -- hub/seal quality, riding/parking/storage conditions, mileage, etc.

Btw, when dkel says "sealed bearing", he means "cartridge bearing." All decent hubs have seals protecting the balls. It's more useful and far less confusing to talk about "loose ball" (which most folks take to include retainer clip designs) vs. "cartridge" bearings.

hozn
05-18-2015, 06:53 AM
My one experience with Shimano cup & cone hubs was in my mtb. The bearings died and ruined the hubs, probably only a thousand (mtb) miles into the life of the wheels. Maybe they were misadjusted; I had no idea what I was doing.

Since then I have always chosen cartridge bearing hubs. Probably depends on the hubs, but so far my cartridge bearing hubs seem to last forever (at least 10k, though I expect double that really) without any servicing.

Crickey7
05-18-2015, 08:26 AM
It really depends on the kind of riding you do. In my experience, a lot of wet-weather riding is what necessitates repacking the bearings, as the water washes the grease out.

Harry Meatmotor
05-18-2015, 09:58 AM
Bike acoustics defy all laws of physics if you ask me.

this is correct almost all of the time.

baiskeli
05-18-2015, 10:20 AM
Well, I took the bike out for an hour today and didn't hear the death rattle. Yah! The LBS replaced two donut shaped thingees (that's a technical term) containing ball bearings in the front hub. I can't believe how loud a bunch of errant ball bearings can be! So a word to the wise, if you have an aluminum frame with a carbon fork and it sounds as if someone is throwing pebbles hard at your frame, get your hubs checked out. And yes, the pings can be very, very loud.

The wheels are only a little over a year old. Am I supposed to get the hubs "serviced" every year? I haven't had anything done to them except this repair.

Thanks for all your help.

Dang, that's exactly what I was going to say, except I didn't because the wheels aren't that old.

If you're riding in lots of rain and mud, it could get in there and put enough grit or rust in there to cause it, or just eat out the grease. It's a good idea to take the hubs apart and clean and regrease them on occasion. But I wouldn't have thought it would need it so fast. Maybe the hub was poorly sealed.

I once had an old hub just freeze up. No noise first, just one day out on the trail the wheel wouldn't turn any more. At least you had some warning. Glad you fixed it.

KLizotte
05-18-2015, 10:48 PM
Humpf. My bike is pampered. I keep it in my apartment and at work it is out of the weather cause I park it under a huge overhang or in the garage. It never sees mud and very rarely rain. I do take it out on the C&O and crushed gravel paths on occasion though.

I checked my old receipts. The hub is an Alchemy Elf which comes standard with WMQ ABEC 5 steel bearings according to the documentation from the manufacturer.

Well, the Elf had better be happy for a while else it is gonna be replaced. It's gonna work to keep a roof over its head!

peterw_diy
05-18-2015, 11:11 PM
That's a cartridge bearing hub. I wonder if the preload was misadjusted and led to premature failure.

My experience with cartridge hubs is mixed. My MTB runs old Phil Wood field serviceable hubs and one of the original cartridges died within the first two months. The others have been fine. But while I only use cartridge bearing bottom brackets, I'm happy with loose ball hubs on my road bikes.

DismalScientist
05-19-2015, 05:28 AM
. So, next year when I bring my bike in for a tune-up I should ask for the hubs to be greased and repacked? I wasn't aware that not doing this could ruin the hubs.


Nope. The "donut thingies (..."containing ball bearings")" they replaced were the cartridge bearings, There should be no problem with the hub going forward.

dkel
05-19-2015, 05:40 AM
Nope. The "donut thingies" they replaced were the cartridge bearings, There should be no problem with the hub going forward.

Unless they were the cones. I just had mine done (my rear hub has loose bearings), and the cone part was looking squirrely, so they replaced that part. The cone doesn't look much like a donut, though, except that it has a hole in it.

KLizotte
05-19-2015, 02:54 PM
The donut thingees looked like this and I found the following info about the hub:

http://bikearlingtonforum.com/attachment.php?attachmentid=8662&stc=1

dkel
05-19-2015, 03:29 PM
That's a cartridge bearing. Those "thingees" usually last a good, long time, and they're fairly weather resistant compared to loose bearings. I'm surprised they gave you trouble.