Bottom bracket threading question.
07-21-09 | 02:34 PM
#1
Thread Starter
Vive la vélorution!
Joined: Oct 2006
Posts: 168
Likes: 1
From: Straight Outta Davis, CA
Bikes: SR PRO-AM
Bottom bracket threading question.
I have a 1977 Puch Marco Polo that came with Shimano Selecta bottom bracket and cranks that I would like to replace/upgrade. I removed everything and now need to buy a new bottom bracket since selecta can't work with square taper cranks, but can't determine the threading I need. Is this bike just standard English/ISO threading.
Any help would be appreciated. Thanks.
Any help would be appreciated. Thanks.
07-21-09 | 07:11 PM
#2
feros ferio
Joined: Jul 2000
Posts: 22,397
Likes: 1,864
From: www.ci.encinitas.ca.us
Bikes: 1959 Capo Modell Campagnolo; 1960 Capo Sieger (2); 1962 Carlton Franco Suisse; 1970 Peugeot UO-8; 1982 Bianchi Campione d'Italia; 1988 Schwinn Project KOM-10;
ISO threading is very likely -- see if there are any 1.37x24 markings on the cups. If you have a known ISO lock ring, see if it spins on freely. If it binds, you probably have French or Swiss threading. For what it's worth, both of my Austrian bikes are ISO-threaded, but I have heard unconfirmed reports that Steyr-Daimler-Puch sometimes used French threading, so there was evidently not a national standard.
__________________
"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
07-22-09 | 12:15 AM
#3
Thread Starter
Vive la vélorution!
Joined: Oct 2006
Posts: 168
Likes: 1
From: Straight Outta Davis, CA
Bikes: SR PRO-AM
So today when I tried to put an ISO threaded cartridge bottom bracket in, the left cup would go in turning it towards the back rim (right). However, the right cup and cartridge would not screw in....
07-22-09 | 02:43 AM
#4
Who cares, just ride it!
Joined: Jun 2006
Posts: 989
Likes: 5
From: Melbourne
Bikes: 1992ish Davidson Impulse, 1981 Apollo Gran Sport SS, 2006 Salsa Las Cruces, 2010 Soma Double Cross
AFAIK Selecta only came in ISO threading, so the bike should be a "standard" 68mm shell with a left hand-thread on the drive side and a right-hand thread on the non-drive side. You state that you got the left-hand side retainer of a cartridge in, which would confirm this.
If you're having trouble getting the cartridge to go in, make sure you clean (and really clean) the threads well. If there wasn't much grease on the threads to begin with, then some corrosion may have built up, which definitely makes a new cup hard to get in. A good idea would be to grease the existing Selecta "cup" and screw it all the way in and out a few times to chase the threads. If not, get hold of a dedicated bottom bracket die.
If you're having trouble getting the cartridge to go in, make sure you clean (and really clean) the threads well. If there wasn't much grease on the threads to begin with, then some corrosion may have built up, which definitely makes a new cup hard to get in. A good idea would be to grease the existing Selecta "cup" and screw it all the way in and out a few times to chase the threads. If not, get hold of a dedicated bottom bracket die.
