# a clunking sound from bike crank?



## raggie33 (May 19, 2009)

its hard to expalin but it drives me crazy its cheap shwin bike i got at target i returned it 2 times already they wont let me retun it again but they say they will fix it but if they are the same folks who put it together i dont trust em.any idea what the sound is.and do ya think if i call the district manager they will help me? original purchase date was march


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## mossyoak (May 19, 2009)

if they dont know how to put it together correctly, i doesnt matter who you talk to, you best bet is to take it to a real bike shop and have them figure out whats wrong with it. its gonna cost a little for someone that actually knows about bikes to fix it. but you know what they say, you get what you pay for.


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## raggie33 (May 19, 2009)

it should still be under warranty and targets 90 day retun is the bad thing id love to just retun it or fix it my self if i knew what was wrong


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## LitFuse (May 19, 2009)

I'd have to agree that taking it to a real bike shop is your best bet. If Target can't assemble it correctly in the first place, you certainly can't expect them to properly diagnose a problem. 

If you ride a lot, your best option is to have a relationship with a local shop. You'd be better off buying a quality used bike from a local shop and letting them service it for you. 

Peter


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## nekomane (May 19, 2009)

raggie, I've had the same problem and had to open up the bottom bracket (shaft and enclosure between the pedals). After many attempts to balance the tightness, finally go it right.

Easiest is to drop by your local bike shop and have an experienced mechanic take a look.
mossyoak's advice is spot on.


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## Flying Turtle (May 19, 2009)

I think you need to give them at least one chance to fix it. If that doesn't work, then talk to the store or district manager. They'll probably either take it to a real bike shop, give you another, or return your money. Try to remain polite, as hard as that might be, but remind them that you have not received a satisfactory product.

Good luck, Raggie.

Geoff


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## raggie33 (May 19, 2009)

i hate takeing stuff to repair shops thats why i learned to build computers and fix cars.i always feel as if they may rip me off.i love the bike other then that dang noise was only 250 and it s fits me.guess illl have to just bring it in to a bike shop though or just ride it till it fails and save for a real bike


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## raggie33 (May 19, 2009)

o i forgot to add at first the front brakes want even hooked up was fun to find out since there are hills every where here on first bike spokes got so lose and its paired spoke wheels i had no idea how to tighten em they aint like reg rims


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## raggie33 (May 19, 2009)

ill try the adjusting thing and to call target again sucks this is my main transportaion


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## glockboy (May 19, 2009)

Try a 1 piece crank, see if the still have a clunking sound.


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## mechBgon (May 19, 2009)

raggie33 said:


> ill try the adjusting thing and to call target again sucks this is my main transportaion


 
Can you post a couple photos of your bike's crank, from the left and right sides?


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## raggie33 (May 19, 2009)

mechBgon said:


> Can you post a couple photos of your bike's crank, from the left and right sides?


yes i will friday cam isnt with me


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## raggie33 (May 19, 2009)

this is the bike btw http://www.amazon.com/dp/B00160JO4Q/?tag=cpf0b6-20


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## mechBgon (May 20, 2009)

raggie33 said:


> this is the bike btw http://www.amazon.com/dp/B00160JO4Q/?tag=cpf0b6-20


 
Ok, that helps narrow things down a little. The crank's axle is supported on bearings, and the bearing parts screw into the frame. If they're not screwed in tight enough, they can rock on their threads, and you get a "clunk" sensation. This could be the issue you're having.

There are two categories of crank-bearing units that your bike might have. The "cup & cone" style can be fully disassembled and requires precise adjustment. The "cartridge" style is factory-adjusted and simply needs to be installed into the frame tightly. Your photos will clarify which of the two types your bike uses. Then I can tell you what tools you'll need and how to use them.

In most cases, you'll need to remove the cranks from the axle to get this problem fixed, so an 8mm or 5/16" hex key to remove the crank bolts, and a proper crank extractor to pull the cranks from the axle, will be essentials. What you'll need after that will depend on which type of crank-bearing unit your bike has.


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## KC2IXE (May 20, 2009)

what is interesting, of course, is that I'm greater than 99% sure that the store never installed the bottom bracket OR the cranks. In general, the way mass market bikes are shipped, you have to put on the front wheel (sometimes back - can't remember), install the pedals, and turn the stem and handlebars straight - plus put air in the tires

The store probably doesn't even HAVE the tools to pull the cranks/Bottom bracket


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## orbital (May 20, 2009)

+

*Just take your bike to an actual bike shop, get a Bottom Bracket overhaul.*

I know you want to do it yourself, but I'll guess you don't have all the tools/torque specs to do an overhaul. 
Obviously it was never installed correctly,... any Bottom Bracket/Crank issue will get much worse.


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## raggie33 (May 20, 2009)

lol waaaa this sucks


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## will (May 20, 2009)

I have an old Schwinn bike that developed a clunk - I have lots of miles on it and one of the pedals went bad. If your clunk is in the crank/pedal area, the clunk will happen when your feet are in the same relative position on each cycle. 

Easy to check - make sure the pedals are tight to the crank arms. Bottom brackets are pretty solid.
Also - make sure the crank arms are not hitting the bottle cage or any thing else.


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## RA40 (May 20, 2009)

Spin the pedals. As well, a quick shot of your favorite mechanical lube might help. 
Could be a bearing in the bottom bracket and that would show-up when spinning them. Just have someone hold up the rear wheel and turn the crank arm and see how it feels. (Don't turn it via the pedal.) 

Not all the bike shops will charge you if it is a quick turn of a wrench for them. This goodwill will bring you back to buy something in the future. 

You should see all the threads about strange noises that come from bikes with some slightly ill fitting part. From the entry level to the mega $$ bikes. Amazing...


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## Patriot (May 21, 2009)

KC2IXE said:


> what is interesting, of course, is that I'm greater than 99% sure that the store never installed the bottom bracket OR the cranks. In general, the way mass market bikes are shipped, you have to put on the front wheel (sometimes back - can't remember), install the pedals, and turn the stem and handlebars straight - plus put air in the tires
> 
> The store probably doesn't even HAVE the tools to pull the cranks/Bottom bracket






Exactly. These bikes normally come from the factory with the BB already installed. All Target has to do is some minor assembly. 

If it makes you feel any better this type of situation isn't all that uncommon even when you are dealing with high end components. The BB can be tricky and on my last build I had to remove it once and start over. Sometimes there's not enough grease in the right place and a simple removal, relube and reinstall takes care of things. On lower end equipment there's always a greater possibility of a problem bearing or something but if you've got replacement parts it's no biggie to change out.


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## raggie33 (May 21, 2009)

i am mad i mean it took me a long time to save to get this bike 250 is a lot to me and i get crap i cant afford to get it fixed unless its something i can do my self i cant belive they dont check this stuff before they send em out


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## mechBgon (May 21, 2009)

raggie33 said:


> I can't afford to get it fixed unless it's something i can do myself


 
If your bike has the problem I suspect, then unfortunately the specialty tools required to fix it yourself will almost certainly cost you more than just having the bike shop do it, even if all you need to buy is the crank extractor and a cartridge-BB tool (one of the simplest cases).



> I can't believe they don't check this stuff before they send 'em out


 
At a decent bike shop, that stuff _does_ get checked before we send 'em out. But we're not a mass-merchant box store... it matters to us that you're happy and safe, not just that we got clean away with $250 of your money before sending you off on a bike with brakes that don't work, etc.


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## es2qy (May 21, 2009)

I echo the others, a bike shop is your best bet. For your wheels, they true in much the same way as regular spokes - right spoke pulls rim to right, left pulls to left, both pulls concentrically, be sure to use a good nipple wrench as paired spokes take high tension. Sorry to hear of your troubles.


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## raggie33 (May 21, 2009)

is it goinjg to get worst i can live with the noise long as it dont break like i said i dont own a car so this is my only transportation


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## nisshin (May 21, 2009)

Here are links to famous DIY bicycle repair/maintenance websites:
Sheldon Brown
Park Tools Repair


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## wmirag (May 21, 2009)

Without seeing your bike (the Amazon picture didn't have enough resolution) , I can't tell if your problem is the same one I had many years ago.

If and only if one or both cranks is secured to the crakshaft with a wedged bolt, read on.
If not, don't bother, I can't help you.

I had a problem where the bolt that secured the pedal was not originally tightened down enough. With repeated hard presssure, the wedge action loosened and I had a clunk upon every downstroke.

I put the threaded end of the bolt into a 1 foot long 3/4" I.D. pipe and pounded the crap out of the bolt head. That seated the wedged bolt firmly against the flat of the crankshaft. Then I tightened the nut at the other end of the bolt. I never heard another peep out of it.

Hope that helps.

W.


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## mechBgon (May 21, 2009)

raggie33 said:


> Is it going to get worse? I can live with the noise as long as it doesn't break. Like i said, I don't own a car, so this is my only transportation.


 
If it's the problem I think it is, then it can potentially get worse, yeah. The crank-bearing unit could continue loosening, with various ramifications. When you get a chance, put up some close-up photos so I can see what type it is.

By the way, most bike shops would charge between $10 and $20 to get this handled, and you can ask them to assess it and give you a price estimate before you have to commit to having it done.


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## orbital (May 22, 2009)

mechBgon said:


> If it's the problem I think it is, then it can potentially get worse, yeah. The crank-bearing unit could continue loosening, with various ramifications. When you get a chance, put up some close-up photos so I can see what type it is.
> 
> By the way, most bike shops would charge between $10 and $20 to get this handled, and you can ask them to assess it and give you a price estimate before you have to commit to having it done.



+1

When I said take your bike into a shop and get a bottom bracket overhaul (or *bottom bracket reinstall* may be better wording), 
I didn't mean to scare you away.

What they need to do is put your bike on the stand, pull off your cranks and bottom bracket.
Then, its putting it all back together with the right wrenches and torque, bit 'o lube....:huh: 
Just be real nice and they'll work with you.

Ask them to snug up your pedals if you haven't already,...they both tighten toward your front wheel....nothing crazy here.

~ If you say its impossible to take your bike in, either you burned your bridges at every bike shop in your area,....or,.....


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## raggie33 (May 23, 2009)

ty everyone lots of options to consider


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## greenpea76 (May 23, 2009)

On my Shimano bottom bracket cartridges, the splined shaft or the tapered square shaft the cranks slips on to, required lube. This is assuming that its a threee piece crank and in the amazon link, it looks like it is. I didn't read through all the posted suggestions, but I am a fairly experienced bicycle mechanic and have dealt with many similar sypmtoms of a popping type clunk sound. Use a thick viscous grease if you can find some at a bike shop or even a hardware store. Target folks that do assembly don't usually know what they're doing when it comes to assembling and lubing components"properly".

I don't know how mechanically inclined your skills are, but most 3 piece cranks require some sort of puller to pull the crank itself away from the bottom bracket. Some can be rocked back and forth a few times and they will come loose. Then coat the bottom bracket shaft liberally with grease and reinstall the crank and torque to proper spec.

There are many vids on youtube that can give you an idea on how to do this. I did a search for "bottom bracket crank removal".

Hope this helps.


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## PhotonWrangler (May 23, 2009)

Raggie, I've had the same clunking behavior on my cheap-o bike. It's annoying but I didn't try to fix it because I'm a complete putz with mechanical stuff and I figured I'd only make it worse if I messed with it. Now I know what the problem is. Thanks for starting this thread!


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## jtr1962 (May 23, 2009)

If it's a cheap Schwinn from Target then it likely has an Ashtabula crank, not the 3-piece type. Bad news is these are much more likely to make all sorts of clunking sounds and otherwise come out of adjustment. Good news is you don't need crank pullers or any special tools to work on them, just a large, adjustable wrench. That being said, if it were my bike I'd buy an adaptor (scroll to middle of page) to convert to the much more reliable 3-piece crank. In fact, I did exactly that on my second bike (an old Huffy).


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## PhotonWrangler (May 23, 2009)

Thanks, JTR. It looks like that Ashtabula crank, so that must be the culprit.


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## orbital (May 23, 2009)

+

This is the bike, those are not one-piece cranks.


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## raggie33 (May 23, 2009)

im not 100 percent sure if the noise is coming from crank but id say 95% or higher its mostly under big loads like when im going up hill.like i said i live on a bottom of a huge hill .the noise realy makes me crazy


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## Coop (May 23, 2009)

This class of bike usually comes with the cheapest of cheap cartridge bottom brackets. The nois usuall comes from damages bearings. Not much to adjust here. The decent quality Shimano square taper Bottom Brackets will usually cost about $15-$20. Having it installed at a bike shop will probably be cheaper than buying the tools to do it yourself (you'll need a crank excractor, BB tool that fits current BB, BB tool that fits new BB too if you're unlucky and a torque wrench. Torque wrench is vital, without it you will most likely over tighten it which is probably the no. 1 cause of BB problems). 

If you take a little care of your bike, the new BB will last you 10 years easily.


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## raggie33 (May 23, 2009)

maybe ill try that i love the bike other then the noise bad thing is it only does it when im going up hill or pedaling very hard.and a course at that point im so tired with pedaling it just gets me madder lol.it has altus in the rear which ive heard aint the rest


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## Coop (May 23, 2009)

I saw somewhere online that the bike you posted the pic of comes with a Shimano BB, this is most likely the low end Shimano UN-26.

I recommend investing a few dollars in getting this one: http://www.jensonusa.com/store/product/BB309F06-Shimano+Un54+Bottom+Bracket.aspx

This model has proven itself over the years and will last you a looooong time when properly installed and taken care of.

Keep in mind that bottom brackets come in a lot of different sizes. You have to look at:

Cup thread (Most likely 'English' for your bike)
Shell width (68mm & 73mm are most common, you can easily measure this by holding a ruler along the crank housing on your bike, measure between the cups)

Spindle length (what you need depends on Shell width and the number of chainwheels on your crank. If you get this wrong, your chainline will be off and shifting will become a pain) 


As there are a lot of factors to take into account, it's best to have it checked at the bikeshop.


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