crunching sound in the pedals
07-22-15, 01:52 PM
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crunching sound in the pedals
So I recently bought a bike like 3 weeks ago, it was of cheaper brand I paid like 270 for it, I guess I got what I paid for but.. was wondering if anyone had any insight on why im getting this "teetery" crunch, when I put force down on the pedals. It only happens on one side, then it happens on the other side and it reciprocates. It has an aluminum frame, and I did check to see if I could find any cracks but I couldnt.
I did "some" research and most signs seems to point to bottom bracket bearings being dirty or shot? I went to the store and they tightened the pedal arms so its not that I guess.
Im gonna try going back again, make them replace the whole crank if I can, I dont think they're good enough to diagnose it.
I hope its not the wheels because apparently I got a warranty for 2 years on everything except the wheels.
I uploaded a youtube, it doesnt show it that well because im not using much force but a small idea on the crunch. The first step doesnt have any crunch but the second does and third you can hear a snapping.
.be; any help would be appreciated.
I did "some" research and most signs seems to point to bottom bracket bearings being dirty or shot? I went to the store and they tightened the pedal arms so its not that I guess.
Im gonna try going back again, make them replace the whole crank if I can, I dont think they're good enough to diagnose it.
I hope its not the wheels because apparently I got a warranty for 2 years on everything except the wheels.
I uploaded a youtube, it doesnt show it that well because im not using much force but a small idea on the crunch. The first step doesnt have any crunch but the second does and third you can hear a snapping.
Last edited by sunbreach87; 07-22-15 at 02:49 PM.
07-22-15, 02:31 PM
#4
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Have your LBS do a BB overhaul , Sound like the bearings are dry and need repacking of fresh grease .
07-22-15, 02:48 PM
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07-22-15, 03:01 PM
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07-22-15, 08:27 PM
#7
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Check & make sure the chain ring bolts are tight. Make sure the crank arms are securely tight onto the crank shaft.
07-22-15, 08:53 PM
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Lots of info here:
https://www.google.com/search?client...est&gws_rd=ssl
https://www.google.com/search?client...est&gws_rd=ssl
07-22-15, 09:39 PM
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Before you do anything else put your finger under the middle of the lower chain loop and measure how much vertical play there is. Not stretching of the chain, but pure slack. Then report back.
I'll bet 3 beers to 2 that the chain is taught, and if so that's the likely issue. Loosen the right axle nut and shift that side of the wheel forward a hair and tighten. Then loosen the left and recenter the wheel between the chain stays.
Same 3 to 2 beers that that solves the problem. Note for future reference proper chain tension is ZERO tension, and proper slack allows the center of either loop to sag about 1/4" in the center.
I'll bet 3 beers to 2 that the chain is taught, and if so that's the likely issue. Loosen the right axle nut and shift that side of the wheel forward a hair and tighten. Then loosen the left and recenter the wheel between the chain stays.
Same 3 to 2 beers that that solves the problem. Note for future reference proper chain tension is ZERO tension, and proper slack allows the center of either loop to sag about 1/4" in the center.
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An ounce of diagnosis is worth a pound of cure.
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“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
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FB
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
07-23-15, 04:45 AM
#10
Mechanic/Tourist
I started a thread a while back about sounds that turn out to be totally different than what you suspect them to be. For example, I had what I thought was a failing bottom bracket. It turned out to be my heel striking the excess cable from my rear brake, producing a "click" sound with every pedal revolution. This is typically a warning that your bottom bracket needs replacement, so I started shopping for one. Once I looked closer and discovered what was really going on, I was as embarrassed as I was relieved. I would look "outside the box" for the cause of your problem. It could even be something inside your shoe that's making the noise!
HOWEVER, your first move is to take it back to the shop and require them to fix the problem before you accept the bike back.
Last edited by cny-bikeman; 07-23-15 at 11:53 AM.
07-23-15, 11:22 AM
#11
Calamari Marionette Ph.D
Before you do anything else put your finger under the middle of the lower chain loop and measure how much vertical play there is. Not stretching of the chain, but pure slack. Then report back.
I'll bet 3 beers to 2 that the chain is taught, and if so that's the likely issue. Loosen the right axle nut and shift that side of the wheel forward a hair and tighten. Then loosen the left and recenter the wheel between the chain stays.
Same 3 to 2 beers that that solves the problem. Note for future reference proper chain tension is ZERO tension, and proper slack allows the center of either loop to sag about 1/4" in the center.
I'll bet 3 beers to 2 that the chain is taught, and if so that's the likely issue. Loosen the right axle nut and shift that side of the wheel forward a hair and tighten. Then loosen the left and recenter the wheel between the chain stays.
Same 3 to 2 beers that that solves the problem. Note for future reference proper chain tension is ZERO tension, and proper slack allows the center of either loop to sag about 1/4" in the center.
My suspicion would be the plastic pedals, just doing what plastic pedals do. Makin' noise.
07-23-15, 08:32 PM
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However, I doubt it's the bottom bracket on a new bike, and is probably something fairly simple that should be easily diagnosed and fixed.
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
08-03-15, 12:58 AM
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Are you sure it isn't your knees ?
08-03-15, 05:20 AM
#14
Senior Member
>>>>>My suspicion would be the plastic pedals, just doing what plastic pedals do. Makin' noise.<<<<<
As I said earlier, think outside the box. Before you go spending all kinds of time and money treating the worst-case scenario, take SquidPuppet's advice and check for dopey little culprits...like cheap plastic pedals.
As I said earlier, think outside the box. Before you go spending all kinds of time and money treating the worst-case scenario, take SquidPuppet's advice and check for dopey little culprits...like cheap plastic pedals.
08-03-15, 05:54 AM
#15
Mechanic/Tourist
The OP had the bike "like 3 weeks" and says there's a 2 year warranty. The only sensible answer is to return it and not accept it back until the problem is fixed. It's up to the shop to determine and resolve the problem. It's been almost 2 weeks since the OP said he'd update us, so hopefully the issue is no longer present.
08-03-15, 01:22 PM
#16
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The OP had the bike "like 3 weeks" and says there's a 2 year warranty. The only sensible answer is to return it and not accept it back until the problem is fixed. It's up to the shop to determine and resolve the problem. It's been almost 2 weeks since the OP said he'd update us, so hopefully the issue is no longer present.
08-10-15, 02:30 PM
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Ok fast forward 3 weeks later or so. The issue was solved.
Turns out, inside the bottom bracket there was some metal scrapings, little curly bits, which looked like it came from the aluminum frame, found its way to near the bearing and was causing the problem(it isnt a closed bearing system). The bearings themselves were fine, however there was also minimal grease, so a lot of synthetic grease was applied. Now it works better than brand new. problem solved.
By the way the pedals are not plastic, they be metal.
Turns out, inside the bottom bracket there was some metal scrapings, little curly bits, which looked like it came from the aluminum frame, found its way to near the bearing and was causing the problem(it isnt a closed bearing system). The bearings themselves were fine, however there was also minimal grease, so a lot of synthetic grease was applied. Now it works better than brand new. problem solved.
By the way the pedals are not plastic, they be metal.
