Re: [CR]Italian vs. British hub threading

(Example: Component Manufacturers)

Date: Sat, 11 Nov 2006 14:49:50 -0500
To: classicrendezvous@bikelist.org
From: "John Betmanis" <johnb@oxford.net>
Subject: Re: [CR]Italian vs. British hub threading
In-Reply-To: <038701c705bb$f90cfe30$2c01a8c0@bike1>
References: <002a01c705af$3969a8f0$6a01a8c0@PC9960>


At 01:05 PM 11/11/06 -0500, Steven Willis wrote:
> I was always told that it was the angle of the thread was different on the
>two.

No, you are confusing the old British 55° Whitworth threads with the now standard 60° threads.

According to Sutherland's, the British and Italian threads are identical except that the Italian diameter is 35mm (1.378") and the English is 1.375". It means that an Italian threaded freewheel on an Englith threaded hub will be a (theoretically) looser fit, resulting in a little less thread engagement. That is why repeated changeing of freewheels or heavy loads could damage the threads. In my opinion, with the amount of hard use and abuse our vintage bikes are likely to get, an Italian threaded freewheel on an English threaded hub is no big deal.

John Betmanis
Woodstock, Ontario
Canada