[CR]re: Outside chainring for 151 campy crank

(Example: Framebuilding:Tubing)

In-Reply-To: <a05200f03bde20613df28@[]>
References: <009b01c4e04d$3fbef7c0$a046fea9@domain.invalid>
Date: Sun, 12 Dec 2004 14:20:06 -0500
To: "Roy H. Drinkwater" <roydrink@ptd.net>, classic list <Classicrendezvous@bikelist.org>
From: "Sheldon Brown" <CaptBike@sheldonbrown.com>
Subject: [CR]re: Outside chainring for 151 campy crank

At 9:45 AM -0500 12/12/04, Roy H. Drinkwater wrote:
>My buddy Tom asked:
>>What was the smallest (least number of teeth) chainring designed as
>>the outside ring for a Campagnolo 151 pattern crank?
> I would be assuming that at the time the crankset was
>designed, half step gearing was still popular. So depending on
>intended use, available freewheel choices, and rider preferences,
>50t to 48t would be the lesser range of the outside ring.
> The Campagnolo records and catalogs I've seen state their
>smallest ring available was 46t. Sugino made 44t & 45T which if
>used could lower the outside ring number, but then the crankset
>looks odd.
> For older cranks, the inner and outer chainrings were generally interchangeable.

44 is the smallest size that will fit in 1/2" pitch.

I've got a comprehensive chart in my Bicycle Glossary, under the "BCD" entry, that shows the minimum size and other data on all of the BCDs I know of, see:


My '61 Paramount came with 52-47, but when I converted it to fixed gear I installed a 26 (1" x 3/16 block chain.)

Sheldon "http://sheldonbrown.com/glossary" Brown Nwtonville, Massachusetts +---------------------------------------------------------+ | Our country is the world - our countrymen are mankind | | --William Lloyd Garrison | +---------------------------------------------------------+ --
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