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


Go Back   > >

Singlespeed & Fixed Gear "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!"-- Henri Desgrange (31 January 1865 - 16 August 1940)

User Tag List

Reply
 
Thread Tools Search this Thread
Old 04-11-06, 03:19 PM   #1
publius
Senior Member
Thread Starter
 
publius's Avatar
 
Join Date: Jun 2005
Location: Longmont, CO
Bikes:
Posts: 198
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Any Crankset I Want?

I'm building up an old frame and need a crank and bottom bracket. I'm looking at a Campy Centaur crank and bb combo on ebay, but I just want to make sure it will be okay. I'm unsure about what gearing I would ultimately use, but I was thinking of keeping the 52/53 on the outside and then using a larger cog in the back (17). Is this a stupid idea? It seems like on FGG those guys all use 42, 44, etc.

Also, any potential problems with aligning my chain and my cog. This seems like something that most people agonize with, but I'm not sure if I understand what to look for so as to avoid the problem altogether since I am buying a new crank and bb.

thanks, tim
publius is offline   Reply With Quote
Old 04-11-06, 03:42 PM   #2
r-dub
likes avocadoes
 
Join Date: Nov 2004
Location: oakland, ca
Bikes: heh, like that info would fit here...
Posts: 1,125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
That's going to give you an 81 or 82 inch gear. Fine if that suits your riding, but I think that the reason many bikes on FGG are in the 42-46 tooth range are because it's easier to get gears in the low-mid 70's inch range (good for street use in many cities) with easily available cogs.
r-dub is offline   Reply With Quote
Old 04-11-06, 03:45 PM   #3
explody pup
Guest
 
Bikes:
Posts: n/a
Mentioned: Post(s)
Tagged: Thread(s)
Quoted: Post(s)
One thing you might want to look into is an adjustable BB, such as the Miche Primato Pista BB.
  Reply With Quote
Old 04-11-06, 03:46 PM   #4
gorn
Senior Member
 
Join Date: Aug 2004
Location: Chi-troit
Bikes: [2004 Bianchi Eros] [1988 Colnago XL Fixed Gear Conversion]
Posts: 577
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
The rings on the campy crank probably are pinned and ramped, this is done to make shifting easier, though it might also make dropping your chain on a single speed easier, which is not a good thing. Also campy cranks use 135BCD which means it's harder to get chainrings for, but Miche makes them, as does Salsa, so you still can get chainrings.

If the crank is a used or NOS one then it might not have pins and ramps.
gorn is offline   Reply With Quote
Old 04-11-06, 04:01 PM   #5
thurstonboise
Senior Member
 
Join Date: Feb 2006
Location: Boise, Idyho
Bikes: '04 fisher 29er, NYC Bikes CityFixed
Posts: 676
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Another thing if this is a road conversion.
A lot of times, people end up having to run on the inside ring to get a decent chainline. A lot of road frames do not have chainstay clearance for a 52t ring on the inside of the spider.
thurstonboise is offline   Reply With Quote
Old 04-11-06, 07:26 PM   #6
nightfly
Senior Member
 
Join Date: Feb 2005
Bikes:
Posts: 1,047
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
I just set up an old set of Sugino Mighty's with the 52 tooth ring on the outside and got a pretty near perfect chainline on a conversion with a 110mm Shimano bb on an old Italvega. Really depends on the bike. Also 52/18 is a pretty decent gear ratio about equal to 46/16 which is what a lot of folks ride. If you've got a local shop that's done some conversion, they can probably steer you in the right direction as far as bb's and chainlines.
nightfly is offline   Reply With Quote
Old 04-12-06, 11:08 AM   #7
publius
Senior Member
Thread Starter
 
publius's Avatar
 
Join Date: Jun 2005
Location: Longmont, CO
Bikes:
Posts: 198
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by nightfly
I just set up an old set of Sugino Mighty's with the 52 tooth ring on the outside and got a pretty near perfect chainline on a conversion with a 110mm Shimano bb on an old Italvega. Really depends on the bike. Also 52/18 is a pretty decent gear ratio about equal to 46/16 which is what a lot of folks ride. If you've got a local shop that's done some conversion, they can probably steer you in the right direction as far as bb's and chainlines.

Thanks to everyone for their advice. Nightfly, do you happen to have any pictures of this bike? I'd be curious to see it.
publius 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 08:47 PM.