Zaphod Beeblebrox 

This is starting to make me a little crazy. I took my '72 Super Course to work last Friday after letting it sit unused for nearly 3 weeks (it was begging to be ridden) and on the way to work I heard, and then felt, a clunking noise coming from the Bottom Bracket. I could feel it in my left foot, I wasn't sure whether it was the pedals or the BB or the Cottered Cranks, but it was fairly loud and could be felt with ever revolution.

Got home Friday Night, checked the cranks for play and thought I felt a little something on the left arm, so I replaced the cotter with a new one and took it for a test. Didn't fix it.

Next I took both arms off, and checked the spindle for play. Again, I thought I felt more than I should. So I repacked the BB using the existing bearings (they were new in March), readjusted the BB, and no a whim decided to repack the pedal bearings as well. Put everything back together and all was well, I did 35-40 miles on it this weekend, and rode it to work Wednesday and Today.

However today the noise was back, and this time it sounds more like a squeak than a thunk, and again I can feel it in my left foot. I don't feel any significant play in the cranks or the pedals...I'm kind of at a loss. A little voice in my head is repeating a mantra saying "You've got Standard Threading, Just go Cotterless and be done with it!"

But i'm hesitant.. I've sort of come to like my cottered cranks.

rhm

How do you remove and install the cotters? Do you have the BikeSmith tool, or do you use something else? Like you, I suspect the cotters first. Possibly if you take out both cotters and reinstall them the other way, that would change something.

Possibly a chain ring bolt is loose? If the spider is swaged to the right crank arm, it might possibly be coming loose, which would be bad.

Possibly the squeak is coming from the chain?

bbattle

Check the seatpost and saddle.

Zaphod Beeblebrox 

I use a hammer to remove em, and a hammer to install em. Matter of fact its the same hammer
I'll try turning them around but I seem to recall that the left cotter only wanted to go in one way, which sorta mandates the direction the right one goes in.

Whats "Suaged" mean? whats the other option if its not suaged?


What should I be checking for? Just making sure its tight?

rhm

Sorry, I meant swaged, which means two pieces of metal were pounded together. The alternative is forged.

See Sheldon Brown:

Chromed steel cranks are almost always swaged to the spider, though there are some forged ones.

_________________________________

It is difficult to seat a cotter pin with a hammer, so the cotters may still be the problem. Pressing them in really is better. I use a vise, cumbersome but effective.

T-Mar

That's a typo. It's swaged, which a means of mechanically attaching two parts. Typically, one part has flange which the other part fits over. In the case of the right crankarm, the spider, usually with integral large chainring, fits over a flange on the crankarm. The flange is than then bent over to attach the two parts, either with a press or hammer.

The alternative is have to the spider cast as one piece with the arm or fit onto splines on the arm.

David Newton

Often the cotters don't exactly fit the angle of the flat on the spindle, and a little filing on the flat of the cotter can mate them up better. That is where the squeak usually comes from, crank arm wobbling on the spindle, but you can usually feel it as you go around.

Seems like old cotters were made from some softer metal then the spindle, to conform to it as you drew it up with the nut, or to deform over some "break-in" time as you would snug the nut up after a while.

Crank Cotters used to be 50 cents for a handful, where do you get them now?

T-Mar

You should be able to get them from any LBS. MY distiibutor still offers 9.0mm (most French and Italian bicycles) and 9.5mm (most Japanese and English bicycles). However, I don't have access to the 8.5mm cotters (some Italian and Mexican bicycles). Of course, you can always drill the crankarms to a larger size. Also, they are now 50 cents each, as opposed to a handful.

Zaphod Beeblebrox 

I got my cotters from eBikestop.com and they were like 4 bux for a pack of 10. I did notice that the left cotter (which I replaced) was a bit deformed when I hammered it out.



Thanks for clarifying the cranks, mine are swaged. Here's a pic.

Sci-Fi

Sounds like the crank arm is loose. Just grease them up (BB spindle/axle and crank arm plus the cotter slot) and then install the cotter pin. The grease will allow the cotter pin to fit more tightly (no matter what tool/method is used for install) as well as make future removals easier. Should be quiet after that. The cotter pins on each side should be installed opposite of each other...ie not on the same side.

What grade of bearings did you use in the BB? Might have gotten a bad batch too.

Sometimes I want to buy a square taper spindle/axle or go cartridge and upgrade the cranks. But I kind of like the look of cottered cranks and it's never really gave me any big headaches. Suppose when the chainring finally wears out, I'll make the change then.

rhm

I use a vise like this one to install / remove cotters. I got it at a yard sale for a couple bucks. A big C-clamp will work too, but the longer the bolt, the more it flexes.

If you reuse a cotter, it may help to file the flat spot flat again; but if you file one cotter, it's a good idea to file the other one to match. If the flats of your cotters are at different angles, your cranks will also be at different angles.

Batman_3000

Unlikely, ok, but it does happen : you get play in the actual pedal cage/etc, not the pedal bearings. To see if it's your cotter pin, how about loosening that cotter pin nut and spraying some lube down there, then tighten up ? If it stops squeeking, you'll know it's the culprit.

Zaphod Beeblebrox 

I'll try greasing down the cotter on the left arm and reinstalling it tonight.

Bearings are stainless...don't know what grade...they were whatever my LBS carries, but I inspected them when I took apart the BB last week and there was no noticeable wear.

I've got a bench vise that I use with a spare socket wrench socket for tough cotters. Maybe I'll try pressing it in with that.

rhm

I'll bet you a beer that takes care of it.

mparker326

Are you sure the squeak isn't coming that nice leather saddle? Does it happen when you stand up and pedal?

Zaphod Beeblebrox 

how'd you see my saddle?!

I'm really like 99% sure its nothing do with the saddle, I can feel something in my foot when I hear the noise.

Rudy, I'll take that bet when I get back from work and hope you win.


**edit**
in the mean time I've dug up like half a dozen auctions for TA, Stronglight and Sugino Maxy cranksets I like...a couple even have some nice drillium.

mparker326

Try switching the pedals and see if you still have the noise.

Zaphod Beeblebrox 

ok, here's the update.

I pressed out the left side cotter, greased and reinstalled a new one and pressed it in with a vise.

No more noise, I only went around the block but I would have heard it in that amount of time...BUT riddle me this: everything feels fine when I'm pedaling, but when I coast (which I do downhills when I am lazy in the morning) and I rotate the cranks slowly just to stretch my legs I can still feel play somewhere, but I can't tell where.

So noise has stopped, beer is quite possibly owed but I want to wait til after i ride it in tomorrow to make that call. I think I'm gonna swap out the pedals like mparker says and see if that makes any difference.

David Newton

You know, those carbon-fiber, ceramic bearing, anodized fixie guys don't have near the fun as all this!

Zaphod Beeblebrox 

They don't know what they're missing

Batman_3000

If the noise reappears in a while, you have a cotter pin/spindle problem, that is the effect of the grease will dissipate and the small amount of play will produce "squeek". Definitely try and replace the pedals, if only by borrowing some to check if the problem is there. Have you checked your freewheel for lateral play ?

rhm

You know what this thread reminds me of? This!

Also this, though I'm sure you have a different problem: my first folding bike was a Strida 3.11 that I got in march 2005. It was on sale, came fully assembled, extremely cool design, and I rode it for about two years before it went into semi-retirement in May 2007 when I got my Downtube Mini. The Strida has a front freewheel system, so both crank arms look like left arms; in fact they are both left arms, but the right one is tapped for a right hand pedal. Anyway, over time the bike developed a floppy feeling that morphed into a clunk in the BB that I could not diagnose. I checked everything (I thought) but couldn't find the problem, and it still felt like the bike was falling apart. This was part of the reason I got the Downtube.

Then the left hand folding pedal on the Downtube broke a couple months later. Needing a quick replacement I thought I'd scrounge one off the Strida. Put the wrench on the left side pedal, turned it a little, and it came off in my hand... complete with a shower of aluminum filings. WTF! On closer inspection I saw the pedal was marked R. And the pedal on the right side was marked L. And the crank arm threads were totally trashed. They had put the pedals in wrong at the factory, and I had ridden the thing 2000 miles like that.

Zaphod Beeblebrox 

Yeah too bad holiday never got a solution to it unfortunately pressing the cotter in was not the Free Beer solution we were looking for this morning's ride was the same as yesterday. click click click...I got sidetracked last night and didn't swap the pedals, so I'm gonna try that after work today.

I'd be upset if it was the pedals... I really like my pedals.

Zaphod Beeblebrox 

rhm was right. It was the cotters. I got it set now (or so it would seem).

I stopped over at the LBS for a pedal cone wrench and a dust cap wrench (neither of which they had) and asked one of the guys to take a quick look. He said he the cotters seemed loose as well.

So i took em both out this evening and installed new cotters, this time using a punch to drive the cotters in (the suggestion of the bike mechanic). Well now they are most definitely IN. and much further than they were before. I'm gonna do a long ride tomorrow, hammer em again when I get back, and call it beer for Rudy.