Clunking noise when I pedal bicycle...what could it be?

[raccoon]

I've already googled this, but this is an old-timey bike with no gears and no hand brakes.

After it had set in a garage for years, I brought it out and had the tires and tubes replaced. It was doing fine until the other day I was riding uphill and then it started clunking whenever I pedal the least bit hard. It doesn't do it while coasting or pedaling gently.

Anybody know?

[taterguy]

1. Your friendly local bike shop would know for sure but I suspect it's a bad crank

[WCGreen]

2. Check your knees...

[WCGreen]

3. Check your knees...

[Pierre.Suave]

4. It means the rear differential is coming loose

you will need to tighten the sprocket joint and lube the shaft...




























:rofl:

[Rabrrrrrr]

5. Sounds like an alternator problem, or maybe the carbeurator.

[SacredCow]

6. It could be just a stiff link in the chain....

While somebody holds the rear wheel up, slowly turn the pedals and watch the chain as it comes off of the rear cogs. A stiff link will stay slightly bent instead of going straight immediately.

To fix it, hit it with some WD-40 and try to loosen it up. You might want to apply some sideways pressure, too (attempt to bend the chain the "wrong" way... But go easy with this procedure). If that doesn't help, or if you see a bunch of stiff links- probably easier to just go get a new chain.

If it's not a stiff link, then it could also be the mechanism in the rear hub (some issues with the coaster brake). I doubt there's a bike shop left in the world that actually repairs those things- it's cheaper and easier to replace the whole rear wheel (probably about $50 or so).

Finally, it could be something with your crank or bottom bracket (the spindle and bearing mechanism on which the crank spins). A bike shop will have to take it apart to verify. Or, if you take the chain off- give the crank a spin. It should spin freely with little to no play. If it sticks, of if there is a noticeable amount of side-to-side play, then you may have found the culprit.

Hope it's the first (and easiest to fix) possibility! :hi:


Edited for bad grammar. I ain't no dang freeper! :rofl:

[jobycom]

7. Is it a fixed gear? Do the pedals turn when you are coasting?

If it is a single, fixed gear, the pedals will continue to turn when you coast. That means the rear hub and the sprocket hub are pretty simple, so it cn only be the chain or the sprocket hub or the rear wheel hub. Since you say it only happens when you pedal, it's probably the bearing in your sprocket hub--the hub the pedals are attached to. It's not likely to be the chain, because the chain would keep turning even when you aren't pedaling, so it would make the noise all the time. The noise would speed up when you pedal faster, too.

If the bike coasts when you pedal, that means the hubs are a little more complicated and that the chain does not turn when you are coasting, so there is more that can be wrong. Nothing moves unless you pedal, so it could be any part of the drive train. Check the chain as the person in the post above suggested. If the chain is fine, try to listen for whether the noise comes from the pedal hub or the rear wheel, and you'll have it narrowed down.

From what you've said, I'm betting the bearings in the sprocket hub are damaged. I've had that happen, and it makes a clunking sound when you pedal, but not when you coast, because you are putting a more uneven pressure on it when you pedal. If it were the chain, you'd feel it clacking each time the bad link hit either sprocket. However, the chain is the easiest thing to replace, so check it first. DON'T put WD-40 on the chain, except on the one link to free it up. That stuff is hard to get off a chain and it will stain your pants or socks when you ride. Plus, it attracts dirt and will start to cake up, messing up the chain further. If it is the chain, they are easy to replace, even if the instructions for doing so sound complicated. Buy a five dollar chain at Target or Walmart or wherever.

If it's the bearing in the sprocket hub, and you have the right tools, first try to tighten the hub--sometimes they are just lose, and that gives the bearings too much play, which will make a clunking sound when you pedal. If it's not loose, take the whole assembly apart and clean the bearings and check for pits in the bearings. There are several types of bearing/crank sets, so you might have to Google for more info if you don't know. Or, just bring it to a bike shop. If you don't have the tools, take it to a bike shop, and they can probably fix it as cheaply as buying the right tools would cost.

That's my summary. :)

[SacredCow]

9. I agree that the bottom bracket (aka sprocket hub) is the most likely culprit...

I doubt the bike is fixed-gear- you really don't see that many of those around anymore (short of track bikes).

If the bike has been sitting for years, and is of a department store variety (Huffy, Murray, Roadmaster, etc...), the little bit of grease that they put in the bottom bracket at the factory is probably bone-dry and/or long gone.

As for the WD-40... If you're getting it on your clothes when you ride, you've got WAY too much on there! It's a marginally-OK chain lube IF you use it correctly (use it VERY sparingly, wipe off the excess, and apply it every single time you ride!). I used it for many, many years during the wet season riding, switching to a silicone lube for the dry months). Nowadays, there are some amazing options out there for chains- White Lightning (Teflon-Impregnated lube) is fantastic stuff...

[Pierre.Suave]

11. you people and your legitimate answers

make baby jesus of the order of the lounge chuggo cry...

[SacredCow]

12. I'm offended....

keep your religion and your chuggo diety to yourself... The lounge is for ALL of us- not just the believers of chuggo...



:rofl:

[Pierre.Suave]

13. Thems fightin words...

:mad:

























:P

[SacredCow]

14. ...

[Pierre.Suave]

15. Oh please...

Chuggo would kick that guys ass...

[SacredCow]

16. Chuggo is imaginary....

not even the skull-stick is real. It's all a sham that the Chuggoists have bought into, hook line and sinker.

[Pierre.Suave]

17. Ohh, you better hide

I smell mayonnaise...

:P

[jobycom]

24. They weren't legite, we were just making it up. nt

[raccoon]

19. Not sure what fixed gear is, but this bike is like the bikes we rode when

we were kids (if you're about 50 or older) :-) No gears, no hand brakes, you use your pedals to brake.

[SacredCow]

20. Pedal backwards to brake (but also have ability to coast) = Coaster Brake...

Fixed gear means that if the bike is moving, then the pedals are moving- there is no mechanism for the bike to "coast" while the pedals remain stationary. It's not a terribly common thing, but there are some devotees- and track bikes (the bikes that are used for velodrome racing) are traditionally of this type.

[DS1]

27. And emo kids, apparently

[Gormy Cuss]

21. That would be what we called "No Speeds" when I was a kid

to differentiate them from those fancy 3 Speeds with the hand brakes.
:P

I think they're technically called "single speed" bikes.

[jobycom]

29. When you stop pedaling, do the pedals keep turning?

That would be a fixed gear. When you ride downhill, the pedals go faster as the bike goes faster, and you wind up with a Yakoff Smirnoff bike--it rides you instead of you riding it. You have to pedal as fast as you can or take your feet off the pedals and let them spin. I had bikes like that when I was a kid. I also had regular single speeds, where the pedals don't spin when you coast. So I wasn't sure which you had.

[raccoon]

31. No. So I guess it's a single speed. nt

[jobycom]

23. Fixed gears are becoming very trendy, for some reason.

People are even converting old single speeds to fixed gears. Purists describe fixed gears the way Rabrrrrr describes Rush, as some sort of spiritual back-to-nature kind of thing.

He said it was an old bike, without gears, so I figured it was at least a possibility.

As for chain lubes, I've seen gunfights break out over them. :) I use White Lightning, mostly. I've used silicone lubes, too. I'm not fanatical enough to maintain the bike after every ride, so I just clean it up when it gets too dirty or when I start to feel guilty. But I've never managed a non-lethal amount, possibly because my father feels about WD-40 the way the father in "My Big Fat Greek Wedding" felt about Windex.

[SacredCow]

30. Yeah, the subject of chain lube to bikers is like Olive Garden in the Lounge...

One of the guys on the team I raced for back in the day would use nothing but paraffin wax on his chains, and was horrified that we all didn't follow suit. But man- what a freakin' process! When part of your bike maintenance includes melting wax on the kitchen stove, something is WRONG!!!!

I haven't been in the loop for a while, so I've not seen the fixed gear thing taking hold. Maybe I should dig the old track bike out of the attic and pretend to be with it... :rofl:

[LostinVA]

34. Especially mountain biking, for some reason

I read a big article about it about a year ago.

[HopeHoops]

8. It is the module

that'll be $400 parts and labor to replace it.

[Beer Snob-50]

10. maybe the clothes pin holding the playing card

shifted and it is the pin smacking against the spokes.

(are you old enough to remember the concept of playing cards against the spokes to make motercycle noises?)

[SoxFan]

18. At my age, probably a knee or ankle

[bikebloke]

22. Does it click on a particular stroke?

When you push down with your right or left foot? It could be pedal bearings? An easy no-tool fix - Lay the bike on its side. Dribble some oil around the pedal shaft where's it's screwed into the crank. There are bearings there and at the other end. Let the oil seep down there, too. Give the pedals a spin now and then.

Otherwise, it could be a kink in the chain. See the poster above for directions.

[raccoon]

36. Good idea, I'll try that. nt

[MrCoffee]

25. Your flux capacitor is shot

You'll never get that thing back to 1955 in that condition.

[DS1]

26. I's guess the pedal itself

[flvegan]

28. Sounds like your cranks are skipping.

You may also notice some "play" in pedal travel. Need to see your local bike shop.

[Arugula Latte]

32. Check to see if someone has chained an anvil to your bike as a prank.

[LostinVA]

33. Bad crank

[Captain Hilts]

35. The bearings going is a possibility. nt

[Whoa_Nelly]

37. Make your bike sound like a motorcycle!

Put playing cards on the spokes
You won't notice the other noise so much after that

http://www.metacafe.com/watch/1451472/make_your_bike_sound_like_a_motorcycle/

[rug]

38. Roadkill.