Bent chainring or cranks?

On Sunday I noticed my drivechain was making more noise than usual - almost a clicking at a particular point of each crank revolution.

Got back home, took chain off and spun the cranks hard whilst holding the seat tube and there's no vibration or noise. So definitely not the bb. No side to side wobble of the spindle, either. It's (Miche) only a couple of months old, not done too many miles, anyway.

Put it all back together, and with the bike upside down, when I spin the cranks you can see the chain move side to side as the cranks go round.

Take off the chainring, lay it flat, with the outside facing up, on a couple of surfaces and one side is raised by about 1-2mm - you can press it up and down.

Take it to Condor and they lay it facing down on a glass counter and say it's fine and to bring the cranks in.

I've watched the cranks go round, and I don't think it's them. I put a bit of blue tack between the chain stays and inside of the spider, and it doesn't move much. Perhaps 0.5 mm? Next to nothing; probably 0.5mm because of me moving rather than the cranks relative to the frame.

I was wondering what anyone else might think it is? I'm taking the cranks to condor tomorrow morning, but i don't see how they're going to test them - just wondered if any of you had any suggestions... takes me ages to get there on public transport plus I've got loads of uni work I'd rather be doing!

Edit: they're condor miche cranks.

sounds strange :S

Yeah, I know :s I'm worried Condor are just going to fob me off. Don't have money for new cranks, either.

Could possibly be a tight link in the chain? You haven't got a half link in there have you?

both my bikes have slightly out of whack crank spiders..

one's noisy, one isn't.

I think these things are common with less expensive cranks and rings..

obivious but clicking cracking noise on down peddle could just require bit of re-greasing before putting back chainset-happened to me after lots of wet riding days?

Could possibly be a tight link in the chain? You haven't got a half link in there have you?

Nope. Bog standard SRAM 1/8" chain. I gave it a proper clean down and then went through every single link with a drop of lube, too. Made no difference at all.

both my bikes have slightly out of whack crank spiders..

one's noisy, one isn't.

I think these things are common with less expensive cranks and rings..

Yeah, it's weird. Slightly disappointing as I spent the extra £50 to get the Miche ones over the Sugino Mess RD thinking I wouldn't get any hassle like this. I just find it really weird it's suddenly started making more noise :-/

obivious but clicking cracking noise on down peddle could just require bit of re-greasing before putting back chainset-happened to me after lots of wet riding days?

Hmm, I don't think it's that because I can see that the chain moves side to side as the cranks rotate. I'll guess I'll find out tomorrow when/if I put them back on.

mine makes alittle bit of noise but i think that it could be abit of chain stretch... whats your tension like?

lightly grease the chainring bolt threads?

If the noise happens at a particular point of each crank revolution, then (unless you are running 1:1 gearing) the problem is with either your cranks, or bottom bracket.
It is not your chain

Sorry, I've just read the OP again. Your chainwheel is bent

Try seeing if the chainring is bent vertically, or offset slightly in the spider bolts
i.e. it moves slightly up and down rather than side to side like you've already ruled out.

That would make your chain slightly tighter at a certain point in the pedal stroke, and cause such a noise, perhaps.
If it's that, there is an excellent article in Sheldon's about it but i can't for the life of me find it right now. It's in the fixed section, somewhere :)

Or alternatively it could be your cog on the rear with a similar problem.

@windy81 the OP said "Put it all back together, and with the bike upside down, when I spin the cranks you can see the chain move side to side as the cranks go round."

RTFT

my reply

"I've watched the cranks go round, and I don't think it's them. I put a bit of blue tack between the chain stays and inside of the spider, and it doesn't move much. Perhaps 0.5 mm? Next to nothing; probably 0.5mm because of me moving rather than the cranks relative to the frame."

thats not even worth mentioning

Loose chainring bolt(s) ?

After you took the chainring off for inspection - did you put it back on to see if the problem was still there ?

lightly grease the chainring bolt threads?

Tried it - made no difference.

mine makes alittle bit of noise but i think that it could be abit of chain stretch... whats your tension like?

I don't think it's chain stretch. The chain is only a couple of months old. Tension is spot on I reckon - 1/2" vertical play.

Try seeing if the chainring is bent vertically, or offset slightly in the spider bolts
i.e. it moves slightly up and down rather than side to side like you've already ruled out.

That would make your chain slightly tighter at a certain point in the pedal stroke, and cause such a noise, perhaps.
If it's that, there is an excellent article in Sheldon's about it but i can't for the life of me find it right now. It's in the fixed section, somewhere :)

Or alternatively it could be your cog on the rear with a similar problem.

I don't reckon it's vertical because when the bike is upside down, if you look down from above, i.e. in the plane of the chain ring, at the chain you can see the part of the chain on the bottom of the chain ring (nearest you) move out one way whilst the other part of the chain on the top (nearest the ground) move out the other way.

I'm pretty sure it's not the cog. EAI on Goldtec, and the chain and cog move round smoothly there, it's between the cog and chainring that you see the chain move laterally.

my reply

"I've watched the cranks go round, and I don't think it's them. I put a bit of blue tack between the chain stays and inside of the spider, and it doesn't move much. Perhaps 0.5 mm? Next to nothing; probably 0.5mm because of me moving rather than the cranks relative to the frame."

thats not even worth mentioning

I know... that's what's puzzling me... When it's all together, you can visibly see the chain move laterally.

Loose chainring bolt(s) ?

After you took the chainring off for inspection - did you put it back on to see if the problem was still there ?

Nope, not chain ring bolts. They were tight when I took it off for the first time. I put it back on yesterday evening, with light grease, and it made no difference.

This is so strange :S Thanks to all your replies so far.

Well, that was a waste of time and £3. Took the cranks in and they said they need to see them on the bike. They bloody told me to just bring the cranks!

You should just buy a new chainring mate... bloody bike shops!

hey eeehhhh,
this sounds eerily similar to a problem i've been having for ages. i hear and feel a sort of clicking at certain points but had no idea what it was for a long time.

i thought i'd finally figured it out—my chainring is extremely close to the chainstays (wide enough to slip a spoke card in, maybe a bit wider), which wasn't a problem for the first six months or so, but when i looked closely at the chainring spinning slowly it seemed to be rubbing the stay slightly at certain points, hence the clicking. i checked again this morning, though, and could feel it clicking, but it was hard to tell if the chainring was actually touching the frame at those moments. after reading your post, i'll try spinning the cranks with the chain off in the morning and see if that's what it is. it's probably unlikely, but is there any chance this is what's happening with your chainring (ie, it's rubbing the stays at certain points)?

what also struck me about your post is that there seems to be lateral movement in my chain, too, except it doesn't move side to side, just looks as though the chain is bent to the side and then bends back again. [sorry if this isn't clear, mechanics aren't my forte and i'm finding it hard to describe, let alone fix] i always thought it was the chain just being full of grit, or slightly bent, but it's a fairly new chain, so i don't know what's wrong.

anyway, let us know if you figure out what is wrong and manage to fix it, i'm curious to know if we have a similar problem, and/or whether this is a common issue for fixed/singlespeeds. cheers.

I reckon it's either that the lengths of the arms on your crank spider aren't all the same - so a manufacturing fault which shouldn't be likely on those miches - or it's your peddling* motion that is pushing the chain off line, maybe try tightening your cleats/straps?

*that's as in turning the pedals not hawking goods ;-)

hey eeehhhh,
this sounds eerily similar to a problem i've been having for ages. i hear and feel a sort of clicking at certain points but had no idea what it was for a long time.

i thought i'd finally figured it out—my chainring is extremely close to the chainstays (wide enough to slip a spoke card in, maybe a bit wider), which wasn't a problem for the first six months or so, but when i looked closely at the chainring spinning slowly it seemed to be rubbing the stay slightly at certain points, hence the clicking. i checked again this morning, though, and could feel it clicking, but it was hard to tell if the chainring was actually touching the frame at those moments. after reading your post, i'll try spinning the cranks with the chain off in the morning and see if that's what it is. it's probably unlikely, but is there any chance this is what's happening with your chainring (ie, it's rubbing the stays at certain points)?

That's what I thought it was at first, but it's not. I rolled blue tack between the frame and chainring wherever it might contact, and it doesn't knock it off.

what also struck me about your post is that there seems to be lateral movement in my chain, too, except it doesn't move side to side, just looks as though the chain is bent to the side and then bends back again. [sorry if this isn't clear, mechanics aren't my forte and i'm finding it hard to describe, let alone fix] i always thought it was the chain just being full of grit, or slightly bent, but it's a fairly new chain, so i don't know what's wrong.

I think I see what you're saying, sounds similar to my case!

anyway, let us know if you figure out what is wrong and manage to fix it, i'm curious to know if we have a similar problem, and/or whether this is a common issue for fixed/singlespeeds. cheers.

I'll be heading back down to Condor on Monday/Tuesday, so I'll post back after then.

I reckon it's either that the lengths of the arms on your crank spider aren't all the same - so a manufacturing fault which shouldn't be likely on those miches - or it's your peddling* motion that is pushing the chain off line, maybe try tightening your cleats/straps?

*that's as in turning the pedals not hawking goods ;-)

I'm beginning to think it's the length of the spider arms as well. Definitely not the pedaling motion because it happens when I'm turning the cranks by hand, and with no pedals on the cranks.

did you get it sorted ?

I have exactly the same problem, just discovered it. My Miche crank is spining side to side, and slightly up & down.. If you find out more would love to know..

Oops, I forgot to reply to this.

Well I took the whole thing to Condor and two guys think it's normal. I'm not convinced, but I'm just going to put up with it :-/

I understand that all cranks have a degree of sideways movement, but I think with the Miche ones it's a bit too much.

Bit of a necro but I don't seem to be able to create a new thread (i'm new, hi everyone).

I havea 2010 Specialised Langster which I use for commuting. I've used it throughout the winter since I bought it last summer and it's had its fair share of rain, mud and road-spoil.

Lately, I've started hearing a creaking/cracking noise as I pedal. I can actually feel small vibrations through my feet which coincide with the noise. I used a to be an avid MTBer a few years ago and I was very used to similar creaking, which i'd understood to be loose cranks (I had a friend who swore by using tin foil to shim the BB spindle, never worked for me mind!).

The cracking and vibration are a little new to me though and I'd rather not clank my way around town so I'd be grateful for advice on what the problem could be and corresponding solution before I empty my wallet for a new crankset.

maybe take the cranks off, (might as well check see if the bottom bracket needs tightening) then re-grease the BB spindle before putting the cranks back on. easy enough fix to try before splashing any cash