Singlespeed & Fixed Gear - cracked campy cranks

so i picked up a pair of old campy pista cranks for next to nothing, knowing full well that there is a tiny (maybe 1/8th" or so) crack where the crank arm meets the spider. apparently this is pretty common. guy sold them to me for $30 bucks and said "if you take a tiny round file and file out the crack they'll be fine." i said wtf $30 bucks i'll give it a try. long story short they've been hanging on my wall for a year...

should i leave 'em there?
or do i try to salvage, anyone have any experience with this situation?

__________________________________

"is this what you do, put a 'lil quote down here?"

Check the Classic & Vintage forums, this is fairly common on older Campy Nuovo and Super Record cranks. I believe you're supposed to drill the end of the crack to stop it from spreading.

I can only imagine what a glorious/hellish crash youd have if it broke in mid-sprint.
I wouldnt ride to 7-11 on em but thats just me not liking to crash.

thanks. drill at the end. sounds smarter than what i've started, which is drilling out the entire crack (read: drilling out the entire crank).
but yeah, i just have this vision of the thing breaking off at a 90 degree angle mid-skid and my knee bone stopping being connected to my thigh bone, or something like this...not worth a pretty drivetrain for all that drama, seen?

I bought my crank for like $35 and that's a fairly recent (almost) midrange road crank, brank spankin' new... Which means it outpreforms your ratty old Campy in every way except for the retrogrouch factor. Looks (Ok, that's personal taste), strength (like, this one will not break in half which I feel to be a relevant factor), weight, stiffness...
Why bother paying for a damaged piece of outdated technology?

I bought my crank for like $35 and that's a fairly recent (almost) midrange road crank, brank spankin' new... Which means it outpreforms your ratty old Campy in every way except for the retrogrouch factor. Looks (Ok, that's personal taste), strength (like, this one will not break in half which I feel to be a relevant factor), weight, stiffness...
Why bother paying for a damaged piece of outdated technology?

but, but, they say campagnolo on them!

Jobst Brandt doesn't seem too worried about it:

http://yarchive.net/bike/crank_break.html

But I was. I bought a set of Nuovo Records on eBay last year that had the crack and returned them for a refund. I didn't want to risk it. For $30, fair enough. They look good and you'll probably get plenty of miles out of them. I definitely wouldn't ride brakeless on them, though!!!

If it is not major , nothing will happen.

I have ridden Campy, Gipiemme cranks road and track.

Just ride and check them every now and then.

S/F,
CEYA!

A crack starts for a reason and will continue to crack under the same circumstances it was created.
Seems to me, it will def break at some point. I mean why would the cracking stop?

well i figured i'd get this kind of mixed response. people seem to believe if you drill out the crack it will stop the progress, kind of like burning the edge of some ripping nylon, well not really anything like that, but kind of, right?

re: making fun of me for wanting to salvage some old, trendy, pretty stuff, well...yeah, i'm like that. and you could say the same thing to anyone in an antique store, vintage shop, or anywhere as such- "hey man, they got perfectly good <fill in the blank, toasters, jeans, etc> at k-mart for half the price and its all brand new. and you'd be right, and guys like me still wouldn't care.

also, good track cranks are not cheap, we're talking about trying to salvage a component that normally sells for around $200 in good condition. just trying to see if its possible, which maybe it isn't.

so thanks to those offering advice/help.

-p

oh yeah - i DO ride breakless, 48/15, so i'm stressing the cranks pretty good...i think i've answered my own question here, maybe i make a door knocker out of these campys...

damned sugino 75's aint that cheap though, perty as they are.

also, good track cranks are not cheap

Niether are medical bills. ;)
And btw, those cranks arent "good". Thats why they cracked. In fact, theyre junk. They were junk when they were new and now theyre even more junk.
Nice to hang on a wall though cause theyre still pretty.
:)

funny thing is i'm sitting here on these forums and velospace and blah blah blah and all the while i have a broken heel. i ain't ridin anywhere.
ever notice how when youre injured all you do is shop and lurk and look for bike stuff online? i think when you can't ride its easy to forget about how RIDING IS THE THING, not bling parts.

anyways, i digress.

i DO ride breakless
not on those cranks you don't!

baZING!

brakes =/ breaks.

Niether are medical bills. ;)
And btw, those cranks arent "good". Thats why they cracked. In fact, theyre junk. They were junk when they were new and now theyre even more junk.
Nice to hang on a wall though cause theyre still pretty.
:)


Sometimes, you say stuff that get me to say "WTF?" sometimes.


Peacer,

PM me about cranks, getting rid of some.

Post a pick of your cranks with the crack.

I do feel the pain of not being able to ride. 16 months so far for me.

S/F,
CEYA!

Thi WAS a Campy road crank on my converted road frame destroyed on a skid

TAKE CARE!!

http://farm1.static.flickr.com/114/286077684_f2462ec546.jpg

To be fair, Campy never sold cranks drilled out like that. The spider should not have had those holes in it, which probably lead to the crank dying in a skid.


Thi WAS a Campy road crank on my converted road frame destroyed on a skid

TAKE CARE!!

http://farm1.static.flickr.com/114/286077684_f2462ec546.jpg

I'm not the most inclined to suggest, but would drilling the hole, filling everything with JB Weld, then sanding it even bring back some integrity?

Just grind out the crack, no need to drill for that length. Check with dye penetrant to make sure you take out all of the crack and you'll have no problems.

Sometimes, you say stuff that get me to say "WTF?" sometimes.


Peacer,

PM me about cranks, getting rid of some.

Post a pick of your cranks with the crack.

I do feel the pain of not being able to ride. 16 months so far for me.

S/F,
CEYA!

Let me re-phrase my og post.
ALL good cranks crack. Yeah, thats what i meant. All of em'.

Originally Posted by deathhare
In fact, theyre junk. They were junk when they were new and now theyre even more junk.

I understand good things break, nothing last forever but the above comment.. .. got my WTF.

S/F,
CEYA!

i know

campy cranks crack because of a design flaw.. they made the spider/arm transition way too fine and the very thin edge fatigues super fast and begins the crack.. over time it grows larger with use and exposure to the elements and may (or may not) lead to total failure.. i think you would be surprised to find out how many people are riding on cracked cranks and never even notice

it is totally possible to repair and prevent further cracking if it's not gone too far..
it also seems prudent to pre-emptively file undamaged yet flawed cranks..
as mentioned, you just need to file out the crack and reshape the spider-to-arm transition
this removes the ultra thin section and corrects the flaw that caused the cracking in the first place


A crack starts for a reason and will continue to crack under the same circumstances it was created.
Seems to me, it will def break at some point. I mean why would the cracking stop?

actually any kinda of sharp edge is a possibility for a stress crack. it doesn't really have anything to do with being too thin. the edge is too sharp.

so does anyone have a picture of one of these that has been "repaired?"

Thi WAS a Campy road crank on my converted road frame destroyed on a skid

TAKE CARE!!

http://farm1.static.flickr.com/114/286077684_f2462ec546.jpg

Holy Balls that's impressive. period.


My 2c.

I once snapped off a spider arm on some CNC crux MTB cranks (impact related). I was working at a shop at the time and one of my regular customers had a business machining helicopter parts. He offered to TIG weld it up free. I said "what the hell", and he zapped them up no problem. This was years before I realized the importance of heat treating, so I never heat treated them, but the same cranks have been holding up to regular riding for about five years now.

actually any kinda of sharp edge is a possibility for a stress crack. it doesn't really have anything to do with being too thin. the edge is too sharp.

um.. ok.. you say 'sharp' i say 'thin'

anyway.. here is an original arm:

http://farm1.static.flickr.com/230/460077224_d3006d6497.jpg

and one filed:

http://farm1.static.flickr.com/227/460077150_019e3608a2.jpg

lol, i figured we were both trying to say the same thing. those photos show exactly what we were talking about...that should help prevent cracks from starting.

campy cranks crack because of a design flaw.. they made the spider/arm transition way too fine and the very thin edge fatigues super fast and begins the crack.. over time it grows larger with use and exposure to the elements and may (or may not) lead to total failure.. i think you would be surprised to find out how many people are riding on cracked cranks and never even notice

it is totally possible to repair and prevent further cracking if it's not gone too far..
it also seems prudent to pre-emptively file undamaged yet flawed cranks..
as mentioned, you just need to file out the crack and reshape the spider-to-arm transition
this removes the ultra thin section and corrects the flaw that caused the cracking in the first place

deathdare inserts pithy comment here

Save the whales

Thi WAS a Campy road crank on my converted road frame destroyed on a skid

TAKE CARE!!

http://farm1.static.flickr.com/114/286077684_f2462ec546.jpg

;___;