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 05-23-05, 01:05 PM   #1
indigosky
Ken Pickles is dead.
Thread Starter
 
indigosky's Avatar
 
Join Date: Apr 2005
Location: No. Yar. ME
Bikes:
Posts: 107
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Chainline help needed...

Ok, here goes. I'm having Carl Strong build me a ss road bike. I have a set of blue Phil Wood Kiss-off hubs in 135mm spacing that I am going to run on the bike (with white velocity deep v rims, drool). I'll have the rear triangle spaced to 135, so my question is this:

I have a line on a C-Record road crank (the most beautiful crank ever made in my opinion), but I want to understand if my chainline will work with the 135 rear spacing. Can I get a Campy triple BB w/ 111mm spacing to work with the crank? How does one figure thie chainline out without trial and error, without buying lot of expensive BB's, and before I have my frame made?

help...
indigosky is offline   Reply With Quote
Old 05-23-05, 01:21 PM   #2
isotopesope
shoot up or shut up.
 
isotopesope's Avatar
 
Join Date: Nov 2003
Location: colorado springs, co
Bikes: yes please.
Posts: 1,961
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
have you looked at this page? http://www.sheldonbrown.com/chainline/
isotopesope is offline   Reply With Quote
Old 05-23-05, 01:29 PM   #3
indigosky
Ken Pickles is dead.
Thread Starter
 
indigosky's Avatar
 
Join Date: Apr 2005
Location: No. Yar. ME
Bikes:
Posts: 107
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
ok, I read that article, and it's saying that my rear hub chainline from center to shoulder is 45.35mm, great, I get that, and my freewheel (white Ind. ENO) is 8.73 from shoulder to chainline. So do I add 45.35 + 8.73 or do I subtract 8.73 from 45.35??? And then how do I know what my chainline on the crank/bb combo will be without it installed on the frame?

Last edited by indigosky; 05-23-05 at 01:41 PM.
indigosky is offline   Reply With Quote
Old 05-23-05, 02:07 PM   #4
indigosky
Ken Pickles is dead.
Thread Starter
 
indigosky's Avatar
 
Join Date: Apr 2005
Location: No. Yar. ME
Bikes:
Posts: 107
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
ok, I re-read it and it says to add the two numbers together, but that results in a chainline of 54.08, which ~seems~ wider than any bb/crank combination listed on sheldon brown.

I (still) don't get it! Am I dense?
indigosky is offline   Reply With Quote
Old 05-23-05, 02:10 PM   #5
techone
dead mileage
 
techone's Avatar
 
Join Date: Aug 2004
Location: London U.K.
Bikes: GT Mtnbike, PaulMilnes Trackbike
Posts: 480
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
First you would need to know what size BB the C record cranks call for as a double.
Your chainline in the rear would be 54.08
And most road doubles use a 46mm chainline on the outer ring, you would need a BB 8mm longer than the original road BB.
Which might be hard to find for campy taper.
techone is offline   Reply With Quote
Old 05-23-05, 02:17 PM   #6
isotopesope
shoot up or shut up.
 
isotopesope's Avatar
 
Join Date: Nov 2003
Location: colorado springs, co
Bikes: yes please.
Posts: 1,961
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
look into possibly getting a phil bb. they're adjustable by 5mm as well, which might help get your chainline correct.
isotopesope is offline   Reply With Quote
Old 05-23-05, 02:33 PM   #7
flythebike
Wher'd u Get That Jacket?
 
flythebike's Avatar
 
Join Date: Sep 2004
Location: Somewhere in the Tubes
Bikes: Calfee Dragonfly, Lemond Poprad, Airborne Manhatten Project, Calfee Luna Fixie
Posts: 1,317
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You can find one...Phil makes lots of really wide square taper bbs that fit campy.

But I don't know for sure how to help without trial and error. The place to start would be normally be to figure your front chainline. Why don't you just pm sheldon brown he's reg'd on this board, or give him a call and ask him. Tell us what he says.
flythebike is offline   Reply With Quote
Old 05-23-05, 04:50 PM   #8
votedean
Drunken Harmonica Band
 
votedean's Avatar
 
Join Date: Mar 2005
Location: Philly / CT
Bikes: Windsor, Schwinn Le Tour, Schwinn Varsity
Posts: 118
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
the mathmatical equation is:
[Over locknut dimension - (cog to inside fork x 2)] / 2 = chainline for rear
Use order of operations. If you don't know order of operations, you shouldn't be trying to figure things like this out. Get your GED. knowledge is power!

Def start with the front. Unless your chainline is wicked off, it'll give you a good reference point to let you know if your math is somewhat correct.
votedean is offline   Reply With Quote
Old 05-23-05, 05:02 PM   #9
dobber
Perineal Pressurized
 
dobber's Avatar
 
Join Date: Oct 2003
Location: In Ebritated
Bikes:
Posts: 6,557
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by votedean
the mathmatical equation is:
[Over locknut dimension - (cog to inside fork x 2)] / 2 = chainline for rear
Use order of operations. If you don't know order of operations, you shouldn't be trying to figure things like this out. Get your GED. knowledge is power!

Def start with the front. Unless your chainline is wicked off, it'll give you a good reference point to let you know if your math is somewhat correct.

Actually that would be from the inside of the dropout to the centerline of the cog.

And wouldn't the chainline be closer to 52mm (45.35 hub + 7.05 DA cog)? Thats about what I got with my fixed Cross-Check. In reality, theres a bit of variation from the advertized values.

And I don't even have a GED.
__________________
This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.
dobber is offline   Reply With Quote
Old 05-23-05, 05:05 PM   #10
jimv
Senior Member
 
jimv's Avatar
 
Join Date: Sep 2003
Location: Seattle, WA
Bikes: Surly Steamroller, Rodriguez (custom SS)
Posts: 391
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by votedean
the mathmatical equation is:
[Over locknut dimension - (cog to inside fork x 2)] / 2 = chainline for rear
Use order of operations. If you don't know order of operations, you shouldn't be trying to figure things like this out. Get your GED. knowledge is power!

Def start with the front. Unless your chainline is wicked off, it'll give you a good reference point to let you know if your math is somewhat correct.
Can't this be simplified to: (O.L.D. /2) - [cog to inside of fork] ??

Jim
jimv is offline   Reply With Quote
Old 05-23-05, 05:23 PM   #11
dobber
Perineal Pressurized
 
dobber's Avatar
 
Join Date: Oct 2003
Location: In Ebritated
Bikes:
Posts: 6,557
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by jimv
Can't this be simplified to: (O.L.D. /2) - [cog to inside of fork]
That requires schooling in Differential Equations and the application of Laplace Transforms.
__________________
This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.
dobber is offline   Reply With Quote
Old 05-23-05, 06:10 PM   #12
votedean
Drunken Harmonica Band
 
votedean's Avatar
 
Join Date: Mar 2005
Location: Philly / CT
Bikes: Windsor, Schwinn Le Tour, Schwinn Varsity
Posts: 118
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by jimv
Can't this be simplified to: (O.L.D. /2) - [cog to inside of fork] ??
Quote:
Originally Posted by dobber
That requires schooling in Differential Equations and the application of Laplace Transforms.
Haha. I knew when I posted it there'd be a select few who'd try to make some sort of quadratic equation or something out of it. Chainline shouldn't require a TI-83. I'm gunna go drink away the math hole I dug myself into.
votedean 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 01:41 AM.