Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 05-03-06, 09:21 PM   #1
TallRider
Senior Member
Thread Starter
 
TallRider's Avatar
 
Join Date: Oct 2005
Location: Fresno, CA
Bikes:
Posts: 4,118
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
possible to replace or reuse cracked crown race for Schwinn Le Tour Luxe?

I've got a Schwinn Le Tour Luxe (from 1983, I think) and am overhauling it to set up as a commuter and semi-nice road bike, for a friend of mine. After stripping everything off the frame and apart (except for removing the headset cups and crown race), I noticed a crack in the crown race. It's a very fine crack, but goes all the way through the crown race. The crack was directly in line with the rear right edge of the fork's lug, so it seems the crack may have come from weight pressing down on the rear of the crown race.

For the time being, I've cleaned the crown race, and reinstalled it on the fork, with the crack lined up in the center of the right fork lug, so that the crown race is supported equally on both sides of the crack. It should work okay.

And I hope it does work okay, because it's a weird, possibly proprietary size. A JIS crown race (27.0mm inside diameter) is too large, and an ISO crown race (26.4mm inside diameter) is too small. It's possible the fork was milled to the obsolete Italian standard with a 26.5mm crown race diameter - the 26.4 won't go on, but it's close to fitting, and the 27.0mm crown race is noticeably too big for the fork.

So I've got three questions:
1) does anyone know offhand what the crown race size for this fork is supposed to be?
2) is it possible to get ahold of these crown races anymore, anywhere? I checked Loose Screws, but they didn't have anything along these lines.
3) will a fine crack in the crown race cause big problems for headset operation down the road? I'm guessing not much, except that the edges of the crack will be a prime spot for pitting, but since I've lined up the crack in a supported position, if I adjust the headset carefully things should work fine for the time being.

Useful reference from Sheldon Brown:
http://www.sheldonbrown.com/cribsheet-headsets.html
TallRider is offline   Reply With Quote
Old 05-03-06, 09:50 PM   #2
Landgolier
THIS SPACE FOR RENT
 
Join Date: Jan 2006
Bikes:
Posts: 2,849
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
This probably occurred to you as well, but I'm betting that it's cracked because the fork wasn't quite milled down to spec, somebody really whacked the race on there, and the metal proceeded to act like metal.

I would run the sucker. It may go eventually, but I wouldn't worry about it. The only other alternative is a replacement fork (possible, every good parts pile has a couple of those bikes), or figuring out a way to slightly ream out an ISO race. You'd probably have to search far and wide for a reamer that size, though I guess you could just go at it by primitive means (emery paper).
Landgolier is offline   Reply With Quote
Old 05-03-06, 11:00 PM   #3
AfterThisNap
Taking "s" outta "Fast"
 
AfterThisNap's Avatar
 
Join Date: Dec 2005
Location: Zoo York City
Bikes:
Posts: 1,989
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Ride it and I doubt you'll notice anything. I rode a DA headset with a cracked race with no problems. Even if it decides to break apart and shoot into a thousand bits when you ride, you will probably still be able to maintain control of the bike...assuming you can still steer.
AfterThisNap is offline   Reply With Quote
Old 05-03-06, 11:08 PM   #4
TallRider
Senior Member
Thread Starter
 
TallRider's Avatar
 
Join Date: Oct 2005
Location: Fresno, CA
Bikes:
Posts: 4,118
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Yeah, I'm thinking that I'm just going to ride it. Or rather, put it back together as-is for my friend. One of the great things about a cracked crown race is that the force from the weight of the bearings is partly pushing inward - which helps to keep the crack in the crown race closed.

As to the cause of the crack, it's possible that the crown itself was just inaccurately reamed, but Schwinn had some funky proprietary things going on back in the day. Also, the crack lined up directly with the edge of the fork crown (the right one, that held the right fork leg), so part of the issue was weight distribution along that edge.
TallRider is offline   Reply With Quote
Old 05-03-06, 11:19 PM   #5
spider-man
Ferrous wheel
 
Join Date: Apr 2005
Location: New Orleans
Bikes: 2004 Gunnar Rock Hound MTB; 1988 Gitane Team Pro road bike; 1986-ish Raleigh USA Grand Prix; mid-'80s Univega Gran Tourismo with Xtracycle Free Radical
Posts: 1,388
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I don't know if it's the same size or not, but I have the crown race off a Katrina-flooded Varsity I salvaged some parts from. I don't need it and would gladly donate it to the cause. PM me if interested.

You might check out the local bike co-op (assuming there is one), too. Here they sell stuff for next to nothing, and not all of it is junk.
spider-man is offline   Reply With Quote
Old 05-04-06, 06:26 AM   #6
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 29,113
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 178 Post(s)
Could you have the fork milled (or remilled) to take a real ISO crown race? My LBS did that for me years ago so I could use an ISO headset on a Bridgestone that came JIS. It took 5 minutes and cost $5.

I expect the cracked race will be ok. I rode with a cracked race for who-knows-how-long a few years ago because I didn't discover it until I gave the bike it's annual overhaul.

BTW, some current FSA headsets come with cracked crown races (they call them "split") but they are cartridge bearing units and the balls don't roll on the race itself. Sure makes for easy installation and removal.
HillRider is offline   Reply With Quote
Old 05-04-06, 07:51 AM   #7
TallRider
Senior Member
Thread Starter
 
TallRider's Avatar
 
Join Date: Oct 2005
Location: Fresno, CA
Bikes:
Posts: 4,118
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally Posted by HillRider
BTW, some current FSA headsets come with cracked crown races (they call them "split") but they are cartridge bearing units and the balls don't roll on the race itself. Sure makes for easy installation and removal.
Very interesting. Makes sense though, actually.
TallRider is offline   Reply With Quote
Old 05-06-06, 10:51 PM   #8
TallRider
Senior Member
Thread Starter
 
TallRider's Avatar
 
Join Date: Oct 2005
Location: Fresno, CA
Bikes:
Posts: 4,118
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Here's a picture of the crack in the crown race. I repacked it with loose balls in the bottom race, and it seems to have close to 100% functionality.
TallRider is offline   Reply With Quote
Old 05-07-06, 06:38 AM   #9
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 29,113
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 178 Post(s)
The race looks to be in pretty good shape and the ball track is smooth with only one minor (we hope) flaw.

As was noted above, even a major failure on the road isn't going to dump you so the liability from continuing to use it is pretty small. The worst possible scenario is the race cracks again at 180° from this one and falls off the fork. The fork collapses against the head tube, you call for a ride home and then go looking for a new bike.
HillRider is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 07:34 AM.