Freewheel threading dilemma

amit said:

I just bought a mostly intact mid-80s Atala in the hopes of making it a
fixed gear bike, but it seems the Rizzato-branded (?) hub is Italian
threaded.

I was able to thread the track cog I had on a turn or so before I
decided I didn't want to ruin the threads.

Italian threaded? I didn't think there was a difference between Italian
hub threads and ISO. I have used lots of old Italian hubs with no
trouble. The only problem I had was with one cheapo cog, which AFAIK may
have been French threaded. All other track cogs, freewheels, even Indian
single-speed freewheels, fit fine.

Hmm, Sheldon does note that there is a difference. But it is small.
Besides, a mid-80s bike would probably be ISO anyway. Maybe the threads
are just screwed up. It was easy to cross-thread those old hubs,
especially since the hub threads were aluminum, but the freewheels were
steel.

--

David L. Johnson

__o | "It doesn't get any easier, you just go faster." --Greg LeMond
_`\(,_ |
(_)/ (_) |

David L. Johnson said:

amit said:

I just bought a mostly intact mid-80s Atala in the hopes of making it a
fixed gear bike, but it seems the Rizzato-branded (?) hub is Italian
threaded.

I was able to thread the track cog I had on a turn or so before I
decided I didn't want to ruin the threads.

Italian threaded? I didn't think there was a difference between Italian
hub threads and ISO. I have used lots of old Italian hubs with no
trouble. The only problem I had was with one cheapo cog, which AFAIK may
have been French threaded. All other track cogs, freewheels, even Indian
single-speed freewheels, fit fine.

Hmm, Sheldon does note that there is a difference. But it is small.
Besides, a mid-80s bike would probably be ISO anyway. Maybe the threads
are just screwed up. It was easy to cross-thread those old hubs,
especially since the hub threads were aluminum, but the freewheels were
steel.

Okay, I was assuming it might be Italian threaded because the cog was
tight on the hub threads. I braced myself and threaded the cog on with
a gloved hand, it definately had a deforming effect on the threads
(slivers of alu were shed) but I was able to thread it on, almost all
the way.

After the "chasing" the cog threads on easily, but the hub and cog
threads were not a great match initially.

Thanks, Amit

-Amit

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

Quoted message said:

David L. Johnson said:

amit said:

I just bought a mostly intact mid-80s Atala in the hopes of making it a
fixed gear bike, but it seems the Rizzato-branded (?) hub is Italian
threaded.

I was able to thread the track cog I had on a turn or so before I
decided I didn't want to ruin the threads.

Italian threaded? I didn't think there was a difference between Italian
hub threads and ISO. I have used lots of old Italian hubs with no
trouble. The only problem I had was with one cheapo cog, which AFAIK may
have been French threaded. All other track cogs, freewheels, even Indian
single-speed freewheels, fit fine.

Hmm, Sheldon does note that there is a difference. But it is small.
Besides, a mid-80s bike would probably be ISO anyway. Maybe the threads
are just screwed up. It was easy to cross-thread those old hubs,
especially since the hub threads were aluminum, but the freewheels were
steel.

Okay, I was assuming it might be Italian threaded because the cog was
tight on the hub threads. I braced myself and threaded the cog on with
a gloved hand, it definately had a deforming effect on the threads
(slivers of alu were shed) but I was able to thread it on, almost all
the way.

After the "chasing" the cog threads on easily, but the hub and cog
threads were not a great match initially.

Thanks, Amit

-Amit

Italian and BSC threads are really close but not the same. Close enough
that the difference is almost negligible, so your experience is right on. .
..

Quoted message said:

Quoted message said:

Quoted message said:

On Sun, 12 Feb 2006 16:55:51 -0800, amit wrote:
>I just bought a mostly intact mid-80s Atala in the hopes of making it a
>fixed gear bike, but it seems the Rizzato-branded (?) hub is Italian
>threaded.
>
>I was able to thread the track cog I had on a turn or so before I
>decided I didn't want to ruin the threads.

Quoted message said:

Quoted message said:

David L. Johnson said:

Italian threaded? I didn't think there was a difference between Italian
hub threads and ISO. I have used lots of old Italian hubs with no
trouble. The only problem I had was with one cheapo cog, which AFAIK may
have been French threaded. All other track cogs, freewheels, even Indian
single-speed freewheels, fit fine.
Hmm, Sheldon does note that there is a difference. But it is small.
Besides, a mid-80s bike would probably be ISO anyway. Maybe the threads
are just screwed up. It was easy to cross-thread those old hubs,
especially since the hub threads were aluminum, but the freewheels were
steel.

Quoted message said:

<[email hidden]> wrote in message

Quoted message said:

Okay, I was assuming it might be Italian threaded because the cog was
tight on the hub threads. I braced myself and threaded the cog on with
a gloved hand, it definately had a deforming effect on the threads
(slivers of alu were shed) but I was able to thread it on, almost all
the way.
After the "chasing" the cog threads on easily, but the hub and cog
threads were not a great match initially.

Wheels by BFWG said:

Italian and BSC threads are really close but not the same. Close enough
that the difference is almost negligible, so your experience is right on. .

BSC hubs are 1.370" x 24t with a 60-degree thread (34.85mm)
Italian hubs are 35mm x 24F with a 55-degree thread

You'll peel up a hair's width curl of aluminum doing that.
If you have a die available, run that with aluminum cutting
fluid ( to prevent galling) before installing your cog.

I don't think that's such a big deal except I'd keep to
modern cogs afterwards (Italian seems no longer to exist).
If there were any problem it would be mounting a larger
(ITA) threaded piece after removing material. Few mechanics
observe the difference and it usually works just fine either
way. I wouldn't use an aluminum cog or freewheel body on
such a modified thread either BTW.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971