Track cranks/bb question

supabonbon said:

What is the major difference between track cranks and regular road
cranks when it comes to chainline issues?=20

Track cranks generally have about a 42 mm chainline, sometimes a bit=20
less. See: http://sheldonbrown.com/chainline

Track cranks most often come in the 165 mm length, which is shorter than =

current fashion for road cranks.

Most track cranks use the old 144 mm bolt circle, while most road cranks =

use the 130 bolt circle.

Track drivetrains commonly use the older, wider 1/8" chain and=20
sprockets, rather than the 3/32" size used for road bikes.

See my fixed gear articles: http://sheldonbrown.com/fixed

Sheldon "Prefers Road Cranks For Road Fixed Use" Brown
+-------------------------------------------------------------+
| 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 derailleur? |
| We are getting soft...As for me, give me a fixed gear! |
| --Henri Desgrange, _L'=85quipe_ article of 1902 |
+-------------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

On 5 Aug 2004 13:59:58 -0700, [email hidden] (supabonbon)

Quoted message said:

What is the major difference between track cranks and regular road
cranks when it comes to chainline issues? I know the spindle length of
the bb is typically shorter, and it seems like track cranks typically
have a larger chainwheel diameter. And maybe track cranks are a little
more built-up.

Contemporary track cranks generally conform to the common chainline
standard of 42.5 mm., plus or minus .5 mm. It's a specification shared
with premium track hub models for compatibility.

As part of our online track catalogue, there's a reference page that
addresses many track-specific issues, including chainline, which you
may find helpful. The link direct to the page is
http://www.businesscycles.com/tr-refspec.htm

-------------------------------
John Dacey
Business Cycles, Miami, Florida
http://www.businesscycles.com
Since 1983
Our catalog of track equipment: online since 1996
-------------------------------

Sheldon Brown said:

supabonbon said:

What is the major difference between track cranks and regular road
cranks when it comes to chainline issues?

Track cranks generally have about a 42 mm chainline, sometimes a bit
less. See: http://sheldonbrown.com/chainline

Does it make sense to speak of chainline for a crank alone?
I had thought that it really only made sense for a BB and crank
combination. At least for square taper cranks, whose BBs are
available in so many sizes that one can adapt them to most any
chainline. Or am I missing something?

supabonbon said:

Quoted message said:

Quoted message said:

What is the major difference between track cranks and regular road
cranks when it comes to chainline issues?

I replied, in part:

Quoted message said:

Quoted message said:

Track cranks generally have about a 42 mm chainline, sometimes a bit
less. See: http://sheldonbrown.com/chainline

Jim Smith said:

Does it make sense to speak of chainline for a crank alone?
I had thought that it really only made sense for a BB and crank
combination. At least for square taper cranks, whose BBs are
available in so many sizes that one can adapt them to most any
chainline. Or am I missing something?

My assumption was that the mysterious "supabonbon" was referring to
standard installations, where the manufacturer's recommended bottom
bracket would be used.

Otherwise, the original question would have been meaningless.

Indeed, if you mix and match bottom brackets, you can do all kinds of
non-standard things with chainline.

Sheldon "http://sheldonbrown.com/chainline" Brown
+--------------------------------------------------------+
| As far as the laws of mathematics refer to reality, |
| they are not certain; and as far as they are certain, |
| they do not refer to reality. --Albert Einstein |
+--------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

"Sheldon Brown" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

supabonbon said:

Quoted message said:

>What is the major difference between track cranks and regular road
>cranks when it comes to chainline issues?

I replied, in part:

Quoted message said:

Quoted message said:

Track cranks generally have about a 42 mm chainline, sometimes a bit
less. See: http://sheldonbrown.com/chainline

Jim Smith said:

Does it make sense to speak of chainline for a crank alone?
I had thought that it really only made sense for a BB and crank
combination. At least for square taper cranks, whose BBs are
available in so many sizes that one can adapt them to most any
chainline. Or am I missing something?

My assumption was that the mysterious "supabonbon" was referring to
standard installations, where the manufacturer's recommended bottom
bracket would be used.

Otherwise, the original question would have been meaningless.

Indeed, if you mix and match bottom brackets, you can do all kinds of
non-standard things with chainline.

Sheldon "http://sheldonbrown.com/chainline" Brown
+--------------------------------------------------------+
| As far as the laws of mathematics refer to reality, |
| they are not certain; and as far as they are certain, |
| they do not refer to reality. --Albert Einstein |
+--------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

Chainline is a very important issue with a fixed-gear. I like the Phil Wood
bottom bracket because it allows me to make fine adjustments to the
chainline. Phil Wood also has a lot of combinations in tapers to chose
from. They have a very good support if you contact them about set-up.
-tom

Quoted message said:

Sheldon Brown said:

Most track cranks use the old 144 mm bolt circle, while most road cranks
use the 130 bolt circle.

I don't know about that. Miche use 135mm BCD, others use 130mm (like my
Truvativ cranks and TA's Alize track crankset) - these are the most
common BCDs I've seen.

In rec.bicycles.tech Zog The Undeniable said:

Sheldon Brown said:

Most track cranks use the old 144 mm bolt circle, while most road cranks
use the 130 bolt circle.

I don't know about that. Miche use 135mm BCD, others use 130mm (like my
Truvativ cranks and TA's Alize track crankset) - these are the most
common BCDs I've seen.

both my miche & suntour track cranks use 144bcd.
--
david reuteler
[email hidden]

"Tom Nakashima" <[email hidden]> wrote

Quoted message said:

Chainline is a very important issue with a fixed-gear.

Surely, you're not *telling* Sheldon this?

-Brendon

I reported:

Quoted message said:

Quoted message said:

Most track cranks use the old 144 mm bolt circle, while most road
cranks use the 130 bolt circle.

A hair splitter piped up:

Quoted message said:

I don't know about that.

I do.

Quoted message said:

Miche use 135mm BCD,

Right. _Only_ Miche uses 135 BCD. Miche is a tiny niche player.

We stock Miche rings for the benefit of folks who want to do fixed-gear
conversions of bikes that have Campgranola cranks.

Quoted message said:

others use 130mm (like my
Truvativ cranks and TA's Alize track crankset) - these are the most
common BCDs I've seen.

None of these are common in track circles (or track ovals, for that matter.)

Much more common are Campagnolo, Shimano, Sugino, Sun Tour, all of which
are 144 except for some ancient 151 stuff.

The 130 size seems to be the "coming thing" but 130 track stuff has
only been around for a handful of years, while the 144 mm standard goe
back to 1967 or thereabouts. Trackies like to stick to 144 because they
often lend chainrings back and forth with their buddies when making
small gearing changes for different events.

Sheldon "I Like 130 Best" Brown
+-------------------------------------------+
| To escape criticism -- |
| do nothing, say nothing, be nothing. |
| --Elbert Hubbard |
+-------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com