Cottered cranck
 

I have an old bike (on the cheap side) that came with cottered cranck, I needed to remove the BB to clean and lub and I was wondering if I should keep it that way or switch everything to cotterless cranck. What do you guys think?

if the crank is adding something to the bike, then try to keep it. if it is just a PITA, remove it and replace the BB and crank.

It really depends. If your cottered crank is ugly and heavy and you have a better cotterless one in your parts bin and all the parts you need to make the switch, then what the heck, do it. Especially if you're making an upgrade that the manufacturer made within a few years of when your bike was made. Like, what's the harm in making an early 70's Super Course more like a later 70's one?

On the other hand, there are some really nice cottered cranks and it would be sad to upgrade a nice cottered one to a crappy cotterless one. Not that you'd be the first one to do that.

Consider why you want to change it - then consider that the weight savings is in a location where it hardly makes any difference, and consider too that cottered cranks are extremely durable and often beautiful.

Also, the difficulty in servicing them is, IMO, way over-blown (provided you have a good cotter press and mill file).

You're right, I want to change it mainly for maintenace purpose, the bike is a 30 years old VÉLO SPORT (cheap canadian made low end bike) so no real value to preserve. The frame is strong so I want to turn it into my commuter (61 kms/day) so I'll need to remove the cranck for maintenance once in a while but I dont have a cotter press.

I have several bikes with cottered cranks. I use a homemade press to remove and install the cotters and have not found them to be a problem. I have heard horror stories but I haven't experienced anything nasty (yet?).
Sandy

stay cottered homie

i have a raleigh sports 3spd with a cottered crank, i had a ***** of time removing them and a ***** of a time replacing the cotters,
once i finally got them back together i vowed i wouldn't never take them a part, i will pour motor oil down the seat tube before i screw with those cotters again, but.... i love the r nuts on the crank, and they keep the vintage of the bike intact soo i have no interest in changing the cranks

It would be good to know (maybe you already do; I don't) if the BB on that bike is French-threaded. When I converted my Gitane, I had to find a longer Italian spindle to make it work with the thin French cups. This may complicate your conversion.

FWIW, I never had much trouble with the cottered cranks. The key as far as I'm concerned is to use a press of some sort in combination with heat (propane torch) to get the cotters out intact, then clean everything thoroughly and slather the cotters with anti-seize compound when you reinstall. You'll never have a problem getting them out again. I only converted that bike because I came across a crankset I really wanted to use, and that bike was the one that suited it best.

If pure function is your aim (I think it is ?) then
by far the easiest way to make this switch is with
the square taper crank set of your choice and
a sealed unit BB in the appropriate threading and
length/offsets.

How did you make your homemade press? I'd like to have one because it would be a lot cheaper to keep everything as is. I just don't want to mess around and search for cotter each time I want to lube the BB. I don't lube the BB that often but when I must I want peace of mind.

is 'cranck' the french canadian spelling? i think i'd change the cottered cranck to a cotterless crank just to avoid the confusion of cranck with crack. crack's wack.

I removed the pins on my cottered crank by loosening the nuts so they were flush with the threaded part, tapping with a hammer to get them lose, remove nuts and press out the rest of the way with my thumb. Install was press the pin in as far as I could and use the nut to draw it the rest of the way. I never had to replace a pin.

In french its 'manivelle' I just mispelled it. Sorry

If you want to improve your french : http://www.infovisual.info/05/034_fr.html

Here's a nice Magistroni 5 pin that won't be replaced with a cotterless. The crank arm might look short but it's because the big ring is a 60 tooth. BTW, what's the file size limit for pics?

thanks

Brian

http://bikeforums.net/attachment.php...hmentid=257518
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oh, please don't apologize for that. i just thought the word looked even more odd than usual. it is an odd word, with many different meanings, including 'an eccentric person' and 'meth' (the narcotic). so, you could write ...

the tired crank took crank to install his crank.

and that's not the worst idea, you know, if you're tired...

My ankles get bloodied from cotters.

just sayin'

I actually installed cottered cranks on a newer bike.
I needed 165MM for my bad knee.
Until I got my new (cheap) 165MM sq.taper cranks, I had an 86 RockHopper 2X9 with the dorkiest looking cranks around.

Sorry for apologizing! ;-)

Thanks - That's a good link - Now I'm equipped to snoop around French eBay !

Nice

You're not supposed to remove them by hitting them with your ankles........just sayin'.

Use a large, cast clamp and an old wrench socket to create a negative space for the cotter to come into as you press it out with the clamp . It seems to be the only way to remove these reliably, other than a cotter press .

In times of desperation, I've used a bench vise with a socket (requires some
wrestling with the frame to position it,) and a twenty dollar drill press vise
from Home Depot (awkward, but less awkward than the bench vise.)

Just don't hammer them.