Threaded Headset - ISO vs. JIS 1"

My late 1970's steel frame is a Cinelli copy that was designed for a 1"
Campy threaded headset. I have always used a Shimano 600 (I've been a
cheapskate for decades), which never fit right in two ways (related?).
The top and bottom fixed cups can still be inserted and removed with
finger pressure; seeing as how there have always been special tools for
'forcing' these into the head tube in perfect alignment I've always
known that this was unusual. Is this the ISO 1" versus JIS 1" issue Dr.
Brown refers to in his glossary entry for headsets?

The second oddity is that the headset has always worked itself loose,
particularly, of course, on bumpy roads. I installed the headset new
from the box, so I know all the parts are there. My suspicion has
always been that the steerer is a little too long and that the locknut
doesn't lock against the adjustible cup. Would that make sense?

I am now 'upgrading' the headset. Campy is still above my price point,
but I'd like to avoid the fit problems I've coped with for 30 years.
I'm looking at a Shimano STX cartridge headset and a Ritchey Logic
headset (they don't put the threaded headsets in the consumer catalog,
so I am unsure of model name/number). Any advice on getting a headset
that fits after all these years?

Thanks.

David wrote:
My late 1970's steel frame is a Cinelli copy that was designed for a 1"
Campy threaded headset. I have always used a Shimano 600 (I've been a
cheapskate for decades), which never fit right in two ways (related?).
The top and bottom fixed cups can still be inserted and removed with
finger pressure; seeing as how there have always been special tools for
'forcing' these into the head tube in perfect alignment I've always
known that this was unusual. Is this the ISO 1" versus JIS 1" issue Dr.
Brown refers to in his glossary entry for headsets?

The second oddity is that the headset has always worked itself loose,
particularly, of course, on bumpy roads. I installed the headset new
from the box, so I know all the parts are there. My suspicion has
always been that the steerer is a little too long and that the locknut
doesn't lock against the adjustible cup. Would that make sense?

I am now 'upgrading' the headset. Campy is still above my price point,
but I'd like to avoid the fit problems I've coped with for 30 years.
I'm looking at a Shimano STX cartridge headset and a Ritchey Logic
headset (they don't put the threaded headsets in the consumer catalog,
so I am unsure of model name/number). Any advice on getting a headset
that fits after all these years?

Thanks.

I would advise you measure the crown race seat on the fork and the
inside of the head tube where the bearing cups seat. And then get a
headset that matches. The crown race seat should be very close to
either 26.4mm, or, 27.0mm. The head tube I.D. should be close to
30.0mm or 30.2mm. ISO headsets are usually 26.4mm for the crown
race and 30.2mm for the bearing cups. JIS is 27.0mm for the crown
race and either 30.0mm (usually), or, 30.2mm (occasionally) for the
bearing cups. If you don't want to end up cutting the steerer tube
you should also measure the stack height and match it as well.
There is no way you can just guess at these measurements. You really
need a set of calipers to do the diameter measurements. You should
certainly be able to find a decent headset in the $20-50 range that
will match your bike. Bearing cups are supposed to be an
interferance fit (i.e. they need to be pressed in). If they are not
tight, as you have described, you should be using a retaining compound
for the installation. Loctite® RC609 is appropriate for this
application.

Here are three good reference pages that you should take a look at:

http://www.parktool.com/repair/readhowto.asp?id=127
http://www.parktool.com/repair/readhowto.asp?id=68
http://sheldonbrown.com/gloss_ha-i.html#headset

Any questions you have should be answered somewhere on those pages.
Good luck.

David wrote:

My late 1970's steel frame is a Cinelli copy that was designed for a 1"
Campy threaded headset. I have always used a Shimano 600 (I've been a
cheapskate for decades), which never fit right in two ways (related?).
The top and bottom fixed cups can still be inserted and removed with
finger pressure; seeing as how there have always been special tools for
'forcing' these into the head tube in perfect alignment I've always
known that this was unusual. Is this the ISO 1" versus JIS 1" issue Dr.
Brown refers to in his glossary entry for headsets?

Could be, or maybe the head tube has stretched. This can happen on
lugless frames if there is no reinforcing ring around the top and bottom
of the tube. How is yours constructed?

The second oddity is that the headset has always worked itself loose,
particularly, of course, on bumpy roads. I installed the headset new
from the box, so I know all the parts are there. My suspicion has
always been that the steerer is a little too long and that the locknut
doesn't lock against the adjustible cup. Would that make sense?

Possible, but it's worth having the faces checked out. Non-parallel
faces cause the same kind of problem and are more common than they
should be.

In the worst case scenario you could have a new head tube and respray
for about $250-300 (the head tube is one of the easier to replace, and
you'd know you were getting ISO tubing). You'd really have to love the
frame though.

If a headset cups fall out of the frame and can be pressed in with your
hands then something is not right. There could be any number of things
going on. If your headset comes loose when you ride you might have a
stack height issue, a spacer inbetween the adjustable race and the
locknut. Campagnolo makes a gauge for headtubes. If there is a camp
pro shop in your neck of the woods then I would suggest taking it in
there. More then just size, if this frame was ridden with a loose
headset for any lenght of time you may have a streched out headtube,
in which case you would need more then just gluing in the headset cups.
If you were to glue in cups you have no idea if the cups are aligned
to each other, and then you'd have serious bearing adjustment issues.
-Tim

Let me revise that, a spacer between the adjustable race and the
locknut would solve that problem. I think I might want to preview my
posts first. lmao

In article , David
wrote:

The second oddity is that the headset has always worked itself loose,
particularly, of course, on bumpy roads. I installed the headset new
from the box, so I know all the parts are there. My suspicion has
always been that the steerer is a little too long and that the locknut
doesn't lock against the adjustible cup. Would that make sense?

No it doesn't. An excessively long steer-tube in of itself shouldn't be
an issue. You can either install the locknut with spacers between it
and the adjustable cup to raise the locknut (for esthetic reasons, so
that it aligns with the top of the steer tube); or install the locknut
sans spacers, and leave a section of the threaded steerer exposed above
it; or cut of the excess length.

What can be a factor when swapping out headsets is the stack height and
its relation to the distance between the fork steerer's threaded
section and the fork crown. This distance can be too great for
headsets with little stack height; the adjustable cup may run out of
thread before it can properly preload the bearings. In this case
regardless of how tight the locknut is against the adjustable cup, the
headset will still be loose. A solution would be extending the threads
further down the steer-tube, or a second headset with a greater
stack-height.

Luke

On Sun, 19 Feb 2006 19:02:29 -0500, Luke wrote:

In article , David
wrote:

The second oddity is that the headset has always worked itself loose,
particularly, of course, on bumpy roads. I installed the headset new
from the box, so I know all the parts are there. My suspicion has
always been that the steerer is a little too long and that the locknut
doesn't lock against the adjustible cup. Would that make sense?

No it doesn't. An excessively long steer-tube in of itself shouldn't be
an issue. You can either install the locknut with spacers between it
and the adjustable cup to raise the locknut (for esthetic reasons, so
that it aligns with the top of the steer tube); or install the locknut
sans spacers, and leave a section of the threaded steerer exposed above
it; or cut of the excess length.

Old-style locknuts had a ridge that would indeed bottom out on the top of
the steerer if it were too long. Yes, an extra washer was a simple
solution, but not all of them would thread past the point where they
bottom out. I had a Campy headset that had this restriction, and a
Shimano one that would allow you to go past that point, but it would push
out a rubber washer in doing so.

--

David L. Johnson

__o | What is objectionable, and what is dangerous about extremists is
_`\(,_ | not that they are extreme, but that they are intolerant.
(_)/ (_) | --Robert F. Kennedy

On Sun, 19 Feb 2006 19:14:14 +0000, Zog The Undeniable wrote:

Could be, or maybe the head tube has stretched. This can happen on
lugless frames if there is no reinforcing ring around the top and bottom
of the tube. How is yours constructed?

A '70s Italian frame is not likely to be lugless.

I suspect, regarding the OP, that someone damaged the frame while prepping
it. I don't believe the frame could be JIS, and if the headset is, then
it would be larger, wouldn't it?

--

David L. Johnson

__o | Some people used to claim that, if enough monkeys sat in front
_`\(,_ | of enough typewriters and typed long enough, eventually one of
(_)/ (_) | them would reproduce the collected works of Shakespeare. The
internet has proven this not to be the case.

"David" wrote in message
news
My late 1970's steel frame is a Cinelli copy that was designed for a 1"
Campy threaded headset. I have always used a Shimano 600 (I've been a
cheapskate for decades), which never fit right in two ways (related?). The
top and bottom fixed cups can still be inserted and removed with finger
pressure; seeing as how there have always been special tools for 'forcing'
these into the head tube in perfect alignment I've always known that this
was unusual. Is this the ISO 1" versus JIS 1" issue Dr. Brown refers to
in his glossary entry for headsets?


I am now 'upgrading' the headset. Campy is still above my price point,
but I'd like to avoid the fit problems I've coped with for 30 years. I'm
looking at a Shimano STX cartridge headset and a Ritchey Logic headset
(they don't put the threaded headsets in the consumer catalog, so I am
unsure of model name/number). Any advice on getting a headset that fits
after all these years?

Thanks.

Your frame is ISO. The Shimano 600 headset you have is possibly JIS,
especially if it was made more than 15 years ago. I have seen several old
600 headsets with JIS dimensions. If you see the stamping "30" on the
headset (underside of the cups), then it is JIS.

Shimano cartridge headsets are excellent. Be careful though, I have seen
STX headsets in both JIS and ISO. As far as bike shop inventory goes, the
ratio between ISO and JIS headsets is now about 1:1. This is despite ISO
headsets fitting 20 times the number of bikes that JIS headsets ever did.
What is left in most shop inventories is the pretty much worthless JIS
models, and most shop employees do not know the difference. I do buy the
Shimano JIS units when they are very cheap (like $10) just to get at the
cartridge bearings and the threaded top parts, and then I throw away the
cups.

In article , David L. Johnson
wrote:

On Sun, 19 Feb 2006 19:02:29 -0500, Luke wrote:

In article , David
wrote:

The second oddity is that the headset has always worked itself loose,
particularly, of course, on bumpy roads. I installed the headset new
from the box, so I know all the parts are there. My suspicion has
always been that the steerer is a little too long and that the locknut
doesn't lock against the adjustible cup. Would that make sense?

No it doesn't. An excessively long steer-tube in of itself shouldn't be
an issue. You can either install the locknut with spacers between it
and the adjustable cup to raise the locknut (for esthetic reasons, so
that it aligns with the top of the steer tube); or install the locknut
sans spacers, and leave a section of the threaded steerer exposed above
it; or cut of the excess length.

Old-style locknuts had a ridge that would indeed bottom out on the top of
the steerer if it were too long.

snip

You're right, I overlooked this. I retract those comments relating to
this fact and apologize for any confusion: If the OP's headset is
configured so, he's making perfect sense - it's me that's not!

Luke