vintage bottom bracket quizzz
#1
car dodger
Thread Starter
vintage bottom bracket quizzz
According to this: https://www.campyonly.com/history/1974/chainlines.pdf
There is a 1mm difference between a 68-SS-120 BB chainline, and a 68-P-120 BB chainline.
I have the 68-SS-120 bottom bracket. So the question now is, where would a campy pista chainring line up on the spindle, closer to the inner or outer chainring, or "centered" at 43.5mm?
There is a 1mm difference between a 68-SS-120 BB chainline, and a 68-P-120 BB chainline.
I have the 68-SS-120 bottom bracket. So the question now is, where would a campy pista chainring line up on the spindle, closer to the inner or outer chainring, or "centered" at 43.5mm?
__________________
1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"
1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"
#2
Old fart
Join Date: Nov 2004
Location: Appleton WI
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The 68-SS-120 is a road spindle, intended for use with double chainrings. If you're using a road crank, running the chainring on the inner plateau should give you a good chainline. If you're using a track crank, you'll want the 68-P-120 spindle (unless you have an old frame with 110mm rear dropout spacing, in which case you'll want the 68-P-110).
#3
car dodger
Thread Starter
I want to use a track crank on a road spindle. The link above indicated that the 2 chainlines are only ~1mm different, assuming my track chainring is at the 43.5 road chainline. I don't want to spend big $ for a track bottom bracket just to perfect my chainline by a millimeter.
__________________
1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"
1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"
#4
Old fart
Join Date: Nov 2004
Location: Appleton WI
Posts: 24,790
Bikes: Several, mostly not name brands.
Mentioned: 153 Post(s)
Tagged: 0 Thread(s)
Quoted: 3590 Post(s)
Liked 3,400 Times
in
1,934 Posts
I want to use a track crank on a road spindle. The link above indicated that the 2 chainlines are only ~1mm different, assuming my track chainring is at the 43.5 road chainline. I don't want to spend big $ for a track bottom bracket just to perfect my chainline by a millimeter.
#5
car dodger
Thread Starter
I did - I think it's pretty close. I measured a hair over 43mm at the chainring, and right at 43mm at the rear cog. I put a 0.5mm spacer between the cog and hub. I haven't ridden it yet but hopefully it will run smooth and silent. Also, there was only ~2mm clearance between the chainring and chainstay. Here's a pic, taken just a few minutes after I finished.
__________________
1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"
1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"
#6
Senior Member
Very nice ride.But i wouldnt worry at all about a 1 or 2mm diff.
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