Go Back  Bike Forums > Bike Forums > Classic & Vintage
Reload this Page >

Is this crank toast?

Notices
Classic & Vintage This forum is to discuss the many aspects of classic and vintage bicycles, including musclebikes, lightweights, middleweights, hi-wheelers, bone-shakers, safety bikes and much more.

Is this crank toast?

Old 02-21-21, 06:10 AM
  #1  
kross57
Senior Member
Thread Starter
 
Join Date: Aug 2018
Location: north NJ
Posts: 691

Bikes: Miyata 710, Univega Viva Sport, Centurion LeMans, Peugeot U09

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 211 Post(s)
Liked 102 Times in 76 Posts
Is this crank toast?

I am working on a mid-80s Peugeot. There is play in the crank where shown by the arrows. Is there any way to fix this, or is the crank arm shot?

kross57 is offline  
Old 02-21-21, 06:18 AM
  #2  
oneclick 
Senior Member
 
Join Date: Feb 2020
Posts: 1,004
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 349 Post(s)
Likes: 0
Liked 333 Times in 213 Posts
Originally Posted by kross57 View Post
I am working on a mid-80s Peugeot. There is play in the crank where shown by the arrows. Is there any way to fix this, or is the crank arm shot?
If the swage between the arm and the spider has become loose it's effectively toast; with the same tooling and press as used to make it it might be fixable, but who has that.
oneclick is offline  
Old 02-21-21, 06:45 AM
  #3  
kross57
Senior Member
Thread Starter
 
Join Date: Aug 2018
Location: north NJ
Posts: 691

Bikes: Miyata 710, Univega Viva Sport, Centurion LeMans, Peugeot U09

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 211 Post(s)
Liked 102 Times in 76 Posts
Originally Posted by oneclick View Post
If the swage between the arm and the spider has become loose it's effectively toast; with the same tooling and press as used to make it it might be fixable, but who has that.
Thanks! That's what I figured, but I wanted to be sure.
kross57 is offline  
Old 02-21-21, 07:31 AM
  #4  
Moe Zhoost
Half way there
 
Moe Zhoost's Avatar
 
Join Date: Sep 2015
Location: Durham, NC
Posts: 2,403

Bikes: Many, and the list changes frequently

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 767 Post(s)
Liked 537 Times in 321 Posts
How much play is there? You could try peening the swage to tighten it up; however it's probably a better idea to scrap it. Sooner or later, you'll find yourself trying to get though an intersection with both crank arms in the 6 o'clock position. Better vintage cranks are not that expensive. French ones are a bit harder to find, though.
Moe Zhoost is offline  
Old 02-21-21, 08:41 AM
  #5  
oneclick 
Senior Member
 
Join Date: Feb 2020
Posts: 1,004
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 349 Post(s)
Likes: 0
Liked 333 Times in 213 Posts
Originally Posted by Moe Zhoost View Post
How much play is there? You could try peening the swage to tighten it up; however it's probably a better idea to scrap it. Sooner or later, you'll find yourself trying to get though an intersection with both crank arms in the 6 o'clock position. Better vintage cranks are not that expensive. French ones are a bit harder to find, though.
They would stay at 180, they're fixed to the crank.

If it slips what happens is pedal, no go.
oneclick is offline  
Old 02-21-21, 09:01 AM
  #6  
Rage
Space Ghost
 
Rage's Avatar
 
Join Date: Oct 2017
Location: NYC
Posts: 1,365

Bikes: 1989 Club Fuji, 1989 Bridgestone RB-1, 1989 Specialized Stumpjumper, 1997 Gary Fisher Big Sur, 2001 GT i-drive Race, Iro Mark V, a bunch more

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 200 Post(s)
Liked 264 Times in 208 Posts
Stick a fork in ‘em to check but I think those cranks are done.
Rage is offline  
Old 02-21-21, 09:17 AM
  #7  
Moe Zhoost
Half way there
 
Moe Zhoost's Avatar
 
Join Date: Sep 2015
Location: Durham, NC
Posts: 2,403

Bikes: Many, and the list changes frequently

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 767 Post(s)
Liked 537 Times in 321 Posts
Originally Posted by oneclick View Post
They would stay at 180, they're fixed to the crank.
Perhaps not. See: https://www.bikeforums.net/classic-v...l#post18816801

Originally Posted by DiabloScott View Post
I remember it well - I was first in line at a left turn lane. When I got the green arrow I attempted my usual explosive acceleration so I could get through the intersection and into the bike lane without holding up the cars behind me. Instead, I got half a revolution of the crank and then suddenly both legs were at 6 o'clock and I had no propulsion. I had to dismount and walk through the intersection while the cars behind me laughed and sneered.
Moe Zhoost is offline  
Old 02-21-21, 09:36 AM
  #8  
oneclick 
Senior Member
 
Join Date: Feb 2020
Posts: 1,004
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 349 Post(s)
Likes: 0
Liked 333 Times in 213 Posts
Originally Posted by Moe Zhoost View Post
I had a look at that. There is no physical way the two crank arms can fail to be aligned at 180 degrees if they each remain attached to their and of the axle - assuming that axle remains intact. The ring - and its swage - are outboard of the crank/axle interface.

And as axles can and do break, I suspect that this is what happened; that the crank was swaged may only be relevant to the point that such cranks are usually built to a lower price-point and their axles may thus be more prone to failure - which may have been the OP's (indirect) point.
oneclick is offline  
Old 02-21-21, 11:34 AM
  #9  
dddd
Ride, Wrench, Swap, Race
 
dddd's Avatar
 
Join Date: Jan 2010
Location: Northern California
Posts: 7,921

Bikes: Cheltenham-Pederson racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.

Mentioned: 112 Post(s)
Tagged: 0 Thread(s)
Quoted: 1045 Post(s)
Liked 473 Times in 337 Posts
Cheap bb spindles can and do fail on occasion. This one let go just as I accelerated onto the main road after ascending from the American River Canyon.
Thankfully not a complete break, and I was able to soft-pedal the two miles to the ride's start/finish!
dddd is offline  
Old 02-21-21, 11:36 AM
  #10  
bikemig 
Senior Member
 
bikemig's Avatar
 
Join Date: Apr 2012
Location: Middle Earth (aka IA)
Posts: 18,130

Bikes: A bunch of old bikes and a few new ones

Mentioned: 156 Post(s)
Tagged: 0 Thread(s)
Quoted: 4967 Post(s)
Liked 1,456 Times in 966 Posts
There is a peugeot branded stronglight crank for sale in the C&V for sale forum.
bikemig is offline  
Old 02-21-21, 11:49 AM
  #11  
DMC707 
Senior Member
 
DMC707's Avatar
 
Join Date: Jan 2013
Location: Oklahoma City
Posts: 4,131

Bikes: Too many to list

Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 991 Post(s)
Liked 312 Times in 213 Posts
Looks nothing like toast. But since going low carb, I haven’t seen a slice in months —-

​​​​​​—— but even if I drizzled melted Kerrygold Irish butter all over it, - that still looks like a damaged crank arm not worth salvaging- whether for a bike or for breakfast
DMC707 is offline  
Likes For DMC707:
Old 02-21-21, 11:49 AM
  #12  
seypat
Senior Member
 
Join Date: Oct 2010
Posts: 5,507
Mentioned: 61 Post(s)
Tagged: 0 Thread(s)
Quoted: 1719 Post(s)
Liked 595 Times in 427 Posts
French toast.
seypat is offline  
Likes For seypat:
Old 02-21-21, 12:54 PM
  #13  
merziac
Senior Member
 
merziac's Avatar
 
Join Date: Oct 2015
Location: PDX
Posts: 7,453

Bikes: Merz x 5 + Specialized Merz Allez x 2, Strawberry/Newlands/DiNucci/Ti x3, Gordon, Fuso/Moulton x2, Bornstein, Paisley,1958-74 Paramounts x3, 3rensho, 74 Moto TC, 73-78 Raleigh Pro's x5, Marinoni x2, 1960 Cinelli SC, 1980 Bianchi SC, PX-10 X 2

Mentioned: 156 Post(s)
Tagged: 0 Thread(s)
Quoted: 2233 Post(s)
Liked 1,363 Times in 927 Posts
Anyone ever try to have one Tigged?
merziac is offline  
Old 02-21-21, 12:59 PM
  #14  
veganbikes
Clark W. Griswold
 
Join Date: Mar 2014
Location: ,location, location
Posts: 8,045

Bikes: Foundry Chilkoot Ti W/Ultegra Di2, Salsa Timberjack Ti, Cinelli Mash Work RandoCross Fun Time Machine, 1x9 XT Parts Hybrid, Co-Motion Cascadia, Specialized Langster, Phil Wood Apple VeloXS Frame (w/DA 7400), Cilo Road Frame, Proteus frame, Ti 26 MTB

Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 2141 Post(s)
Liked 1,075 Times in 753 Posts

This is toast those are cranks. Those cranks are probably not one I would want to ride on but not toast, do not eat.
veganbikes is offline  
Old 02-21-21, 01:51 PM
  #15  
bertinjim 
Senior Member
 
bertinjim's Avatar
 
Join Date: Mar 2012
Location: Niagara Region, Canada
Posts: 1,274

Bikes: 1960s Bertin C37, 1973 Carre Bertin C 37, 1970s Carlton Kermesse, 1982 Peugeot PB 12

Mentioned: 40 Post(s)
Tagged: 0 Thread(s)
Quoted: 270 Post(s)
Liked 100 Times in 70 Posts
That's a Stronglight 5470 crankset that's a look-alike for the Stronglight 104. The 104 was a solid spider, not swaged and the chainrings are fully interchangeable.
bertinjim is offline  
Old 02-21-21, 03:45 PM
  #16  
Moe Zhoost
Half way there
 
Moe Zhoost's Avatar
 
Join Date: Sep 2015
Location: Durham, NC
Posts: 2,403

Bikes: Many, and the list changes frequently

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 767 Post(s)
Liked 537 Times in 321 Posts
Originally Posted by oneclick View Post
I had a look at that. There is no physical way the two crank arms can fail to be aligned at 180 degrees if they each remain attached to their and of the axle - assuming that axle remains intact. The ring - and its swage - are outboard of the crank/axle interface.
You are absolutely correct. The thread I referenced sent my head on a detour. A failure of the swage would at worst result in the crank arm spinning on the motionless chainring.

Cheers, mate.
Moe Zhoost is offline  
Old 02-21-21, 04:25 PM
  #17  
homelessjoe
Senior Member
 
Join Date: Nov 2014
Location: Ann Arbor Michigan
Posts: 152

Bikes: miyata 83 1000,84 1000,83 610,88 ridge runner ,Schwinn 84 high sierra,88 Cimmeron,86 Passage,84 Stumplumper ,83 Mt Whitney,83 Trek 850,Merckx Century,PX10, RB1,XO 1 XO 4,bunch of stuff like that

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 54 Post(s)
Liked 44 Times in 36 Posts
I had that same crank on a late 80s UO10 and it started to loosen up then the drive side crank arm broke right in half.Never saw that before.Very low miles
homelessjoe is offline  
Old 02-21-21, 04:30 PM
  #18  
francophile 
PM me your cotters
 
francophile's Avatar
 
Join Date: Jun 2015
Location: ATL
Posts: 3,696
Mentioned: 73 Post(s)
Tagged: 0 Thread(s)
Quoted: 1049 Post(s)
Liked 448 Times in 345 Posts
Post a pic of the other side. Strong possible I may have a replacement I can send over. Can't tell if it's one of the Nervar arms or if it's one of the Peugeot-branded Stronglight cranks, although I don't think the latter came in swaged format. I can't recall which ones were swaged otoh.
__________________
███████████████

francophile is offline  
Old 02-21-21, 04:44 PM
  #19  
rjhammett
Senior Member
 
rjhammett's Avatar
 
Join Date: Dec 2011
Location: Saint Paul, Minnesota
Posts: 2,161

Bikes: 92 Colnago Master PIU, 85 Fuso, 92 Bridgestone RB-1, 83 Pinarello Record, 92 Tommaso, 92 Merckx MX Leader, 90 Serotta Colorado II, 99 Tommasini Sintesi, 90 Pinarello Montello, 89 Tommasini Super Prestige, 08 Look 585 and 8 more

Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 273 Post(s)
Liked 226 Times in 116 Posts
I am not one to give up on bike parts without trying to fix them. If it was me that had this issue I would put the arm on a solid surface and find a socket or pipe that is just a little smaller than the crank arm flange on the back of the arm and give it a good whack with a sledge hammer to see if it would tighten up. Once I tried that and found out that it didn't work (most likely result) I would toss it.
rjhammett is offline  
Old 02-21-21, 04:56 PM
  #20  
JohnDThompson 
Old fart
 
JohnDThompson's Avatar
 
Join Date: Nov 2004
Location: Appleton WI
Posts: 22,336

Bikes: Several, mostly not name brands.

Mentioned: 131 Post(s)
Tagged: 0 Thread(s)
Quoted: 2495 Post(s)
Liked 1,028 Times in 666 Posts
FWIW, @marius.suiram has a Peugeot-branded Stronglight 104 crank in the "For Sale": forum:

https://www.bikeforums.net/classic-v...l#post21934227

This is a one-piece (not swaged) crank; not sure if it is forged or cast, but either way a step up from the failed swaged crank.
JohnDThompson is offline  
Likes For JohnDThompson:
Old 02-21-21, 08:53 PM
  #21  
Chombi1 
Senior Member
 
Chombi1's Avatar
 
Join Date: Nov 2015
Posts: 3,363
Mentioned: 94 Post(s)
Tagged: 0 Thread(s)
Quoted: 1185 Post(s)
Likes: 0
Liked 218 Times in 164 Posts
Originally Posted by rjhammett View Post
I am not one to give up on bike parts without trying to fix them. If it was me that had this issue I would put the arm on a solid surface and find a socket or pipe that is just a little smaller than the crank arm flange on the back of the arm and give it a good whack with a sledge hammer to see if it would tighten up. Once I tried that and found out that it didn't work (most likely result) I would toss it.
Maybe it will be better to use a nice big brnch vise (with a cheater pipe to increase amount of pressure) to press the socket against the flange, instead. A vise will provide a similar even pressure that the press in that factory did on the flange that hitting it with a hammer won't likely do.
__________________
72 Line Seeker
83 Davidson Signature
84 Peugeot PSV
84 Peugeot PY10FC
84 Gitane Tour de France.
85 Vitus Plus Carbone 7
86 ALAN Record Carbonio
86 Medici Aerodynamic (Project)
88 Pinarello Montello
89 Bottecchia Professional Chorus SL
95 Trek 5500 OCLV (Project)
Chombi1 is offline  
Old 02-21-21, 09:22 PM
  #22  
ramzilla
Senior Member
 
ramzilla's Avatar
 
Join Date: Dec 2014
Location: Fernandina Beach FL
Posts: 3,472

Bikes: Vintage Japanese Bicycles, Tange, Ishiwata, Kuwahara

Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 676 Post(s)
Liked 259 Times in 206 Posts
It's done. That's it. That's all. Done deal. Be good. Have fun.
ramzilla is offline  
Old 02-21-21, 10:48 PM
  #23  
scarlson
Senior Member
 
scarlson's Avatar
 
Join Date: Jun 2010
Location: Medford MA
Posts: 1,212

Bikes: Ron Cooper touring, 1959 Jack Taylor 650b ladyback touring tandem, Vitus 979, Joe Bell painted Claud Butler Dalesman, Colin Laing curved tube tandem, heavily-Dilberted 1982 Trek 6xx, René Herse tandem

Mentioned: 43 Post(s)
Tagged: 0 Thread(s)
Quoted: 525 Post(s)
Liked 644 Times in 372 Posts
Originally Posted by merziac View Post
Anyone ever try to have one Tigged?
I think it's not wise, but unlike many welders, I will tell you why. The alloys may be different between the crank arm and the spider, and either or both might be "not weldable" alloys. You _could_ weld them, but they wouldn't have much strength due to the way the metal grain precipitates after welding. I'm guessing a crack would start somewhere.

If I ever have access to tig equipment again, I'm happy to try!!
scarlson is offline  
Likes For scarlson:
Old 02-21-21, 11:32 PM
  #24  
thook
Senior Member
 
Join Date: Aug 2009
Location: Winslow, AR
Posts: 1,608

Bikes: '83 univega gran turismo x2, '85 schwinn super le tour,'89 miyata triple cross, '91 GT tequesta, '90 yokota grizzly peak, '94 GT backwoods, '95'ish scott tampico, '98 bonty privateer, '93 mongoose crossway 625, '98 parkpre ariel, 2k'ish giant fcr3

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 360 Post(s)
Liked 222 Times in 164 Posts
https://weldingmagazine.com/can-you-...C...%20More%20
thook is offline  
Likes For thook:
Old 02-22-21, 12:43 AM
  #25  
merziac
Senior Member
 
merziac's Avatar
 
Join Date: Oct 2015
Location: PDX
Posts: 7,453

Bikes: Merz x 5 + Specialized Merz Allez x 2, Strawberry/Newlands/DiNucci/Ti x3, Gordon, Fuso/Moulton x2, Bornstein, Paisley,1958-74 Paramounts x3, 3rensho, 74 Moto TC, 73-78 Raleigh Pro's x5, Marinoni x2, 1960 Cinelli SC, 1980 Bianchi SC, PX-10 X 2

Mentioned: 156 Post(s)
Tagged: 0 Thread(s)
Quoted: 2233 Post(s)
Liked 1,363 Times in 927 Posts
Originally Posted by scarlson View Post
I think it's not wise, but unlike many welders, I will tell you why. The alloys may be different between the crank arm and the spider, and either or both might be "not weldable" alloys. You _could_ weld them, but they wouldn't have much strength due to the way the metal grain precipitates after welding. I'm guessing a crack would start somewhere.

If I ever have access to tig equipment again, I'm happy to try!!
Atta boy!
merziac is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.