[CR]Bass-ackward BB on Hetchins

(Example: Framebuilders:Mario Confente)

From: "David Bean" <beandk@rcn.com>
To: "CR List (E-mail)" <classicrendezvous@bikelist.org>
Date: Fri, 21 Mar 2008 19:12:47 -0400
Subject: [CR]Bass-ackward BB on Hetchins

I decided the BB spindle on the Hetchins Italia I just received from England was too short to use with the intended crank, so I took it to Steve Birmingham's shop, where they had the special Campag Mirage spanner to remove the rings. I was a bit flummoxed because they seemed to be turning the wrong way, but maybe I'd drunk too much coffee. After a nice conversation with Steve about his cool ancient motor-pacing bike, I went home and reexamined things. Sure enough, the threading is backwards. I still have a hard time believing it.

The DRIVE side tightens up by turning it CLOCKWISE (right hand thread), the nondrive side tightens counterclockwise (left hand)! The rings are marked 1.370x24tpi. BB shell is Nervex, stamped "HET" and is 68mm wide.

How the heck could this happen? A tyro got it backwards with the taps?

And what should I do about it? (A lockring on the drive side might raise eyebrows...) Would it be best to use a sealed BB so the turning of the spindle doesn't have a direct effect on the fasteners?

David Bean
Arlington, MA USA
beandk at are-see-enn dot com