JIS vs ISO headset.
Wayne Pein
Thanks,
Wayne
landotter
> Will a JIS headset work on a "modern" standard 1 inch headtube?
>
> Thanks,
> Wayne
Nope, it'll be too loose. You can go the other way around, I've got a
tange JIS fork on one of my bikes that I ground down to fit an ISO headset.
Ozark Bicycle
Maybe, maybe not; it depends on the ID of your head tube and the OD of
the fork crown.
Here's a listing of the JIS v. ISO ("modern european" standards, from
the very helpful Park Tool site:
Scroll down to "Headset Sizing Standards"
Werehatrack
have said:
>Will a JIS headset work on a "modern" standard 1 inch headtube?
If it's a modern standard 1 inch JIS tube, yes. If it's not a
JIS-size tube, then no, regardless of the era in which it was made.
The difference between the JIS headset and the more common type is in
the ID of the crown race; the rest of the dimensions are the same.
--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.
Dave Mayer
"Wayne Pein" <wp...@nc.rr.com> wrote in message
news:45bfe50c$0$1403$4c36...@roadrunner.com...
> Will a JIS headset work on a "modern" standard 1 inch headtube?
>
> Thanks,
> Wayne
>
cups. JIS models are used in cheap Asian-made frames. However, based on my
experience, more than half of the headsets for sale in shops or mail order
are JIS - simply due to attrition. Basically, almost all of the remaining
ISO headsets have been bought out of stock, and the remaining inventory left
over since the conversion to threadless and 1 1/8" are the leftover and
useless JIS models.
JIS cups have a diameter of 30.0mm where they are press into the frame. ISO
is 30.2mm. On normal frames, the JIS cups will be loose. This will cause
dodgy steering and braking and if ridden, and will cause headset cup and
frame damage due to the loose fit.
Second difference is the crown race. JIS is 27.0mm. ISO is 26.4mm. The
JIS race will rattle around on a normal fork. It will be completely
unusable.
Take the JIS headset back to where you got it from and get a refund. Just
like the previous 5 folks who bought this same orphaned headset and
eventually realized the same thing that you did. The shop that sold it
either does not understand the difference between the two, or they hoped
that they could just (finally!) unload it on someone that would not
complain. Either way, you should make the situation right.
Been there.
Peter Cole
I managed to make it work on the one bike I tried. The frame to cup
difference is only .2mm, in my case the frame paint apparently was
enough for a snug fit. I shimmed the crown race (.6mm) with thin
aluminum sheet stock.
I did this a couple of years ago on a steel framed bike. It's held up so
far, probably 1k miles or so. I don't expect any problems from it.
Wayne Pein
Dave,
I think you are right on the mark. In the near future I plan on buying
two new steel frames for my wife and me, probably Heron Rallys
http://www.heronbicycles.com/, and I've been accumulating new Ultegra
6500 9 speed parts. The latest purchase was front 28.6 clamp derailleurs
(a modern high-end size) and 1 inch headsets from the same mail order
vendor. There was no mention of JIS or ISO on headset choice on the
website. I therefore didn't even consider the possiblity. Upon receiving
the order, one of the headset plastic bag packages clearly shows it as
JIS. It was previously opened and re-closed with staples. The other
headset package is unmarked, but it is the same JIS size. If the one
package didn't have the label, I would have never known the size
discrepancy, and when I tried to build the bikes I would have been
pulling my hair out with frustration.
Wayne
Marcus Coles
While most of your commentary is correct, the perception that JIS head
set were/are only used on cheap frames is wrong.
They were also used on midrange to high end bicycles from Japan and I
believe still common on Keirin bikes.
Dura-Ace JIS headsets are out there as well as the Hatta Swan Super
Deluxe, not exactly something one would install on a "cheap Asian-made
frame".
Marcus
Donald Gillies
>The difference between the JIS headset and the more common type is in
>the ID of the crown race; the rest of the dimensions are the same.
Tell that to Gina Morey <gsm...@earthlink.net>, who cracked their
head-tube installing an ISO headset into a JIS bike, the overly large
ISO headtube caused cracking of the lug at the bottom of the head
tube.
- Don Gillies
San Diego, CA
Donald Gillies
>The difference between the JIS headset and the more common type is in
>the ID of the crown race; the rest of the dimensions are the same.
Tell that to Gina Morey <gsm...@earthlink.net>, who cracked their
head-tube installing an ISO headset into a JIS bike, the overly large
ISO headset caused cracking of the lug at the bottom of the head tube.
Werehatrack
have said:
Oddly enough, the JIS headsets I've got here (two of them, but neither
guaranteed to have what was supposed to be in them) both have cups
whose head tube flange measures 30.2mm. I suspect that they're
probably quite malleable in that area, however; these are just Tange
bottom-feeder quality. Or, at least, that's what's marked on the
boxes.
I've been measuring a bunch of headset bits lately in an effort to
find one with a crown race that will work on an ancient Rollfast
tandem. Bloody thing's steerer shoulder is a trifle smaller than
what's supposed to be on a common one-piece-crank fork.
Ozark Bicycle
> On 1 Feb 2007 12:07:01 -0800, gill...@cs.ubc.ca (Donald Gillies) may
> have said:
>
> >Werehatrack <raul...@earthWEEDSlink.net> writes:
>
> >>The difference between the JIS headset and the more common type is in
> >>the ID of the crown race; the rest of the dimensions are the same.
>
> >head-tube installing an ISO headset into a JIS bike, the overly large
> >ISO headset caused cracking of the lug at the bottom of the head tube.
>
> Oddly enough, the JIS headsets I've got here (two of them, but neither
> guaranteed to have what was supposed to be in them) both have cups
> whose head tube flange measures 30.2mm.
I think you may have something that is/was being sold as a "semi-JIS"
headset, i.e., ISO cups and a JIS crown race. These can be useful for
putting a JIS fork on an ISO frame.
> I suspect that they're
> probably quite malleable in that area, however; these are just Tange
> bottom-feeder quality. Or, at least, that's what's marked on the
> boxes.
Indeed, Tange is the brand I've seen on those "semi-JIS" headsets.
Werehatrack
<bicycle...@ozarkbicycleservice.com> may have said:
>On Feb 1, 2:25 pm, Werehatrack <raul...@earthWEEDSlink.net> wrote:
>> Oddly enough, the JIS headsets I've got here (two of them, but neither
>> guaranteed to have what was supposed to be in them) both have cups
>> whose head tube flange measures 30.2mm.
>
>I think you may have something that is/was being sold as a "semi-JIS"
>headset, i.e., ISO cups and a JIS crown race. These can be useful for
>putting a JIS fork on an ISO frame.
>
>> I suspect that they're
>> probably quite malleable in that area, however; these are just Tange
>> bottom-feeder quality. Or, at least, that's what's marked on the
>> boxes.
>
>Indeed, Tange is the brand I've seen on those "semi-JIS" headsets.
That would explain it. Thanks; I'll re-mark them and set them aside.
I still have to find a crown race to fit that blasted Rollfast.
Ozark Bicycle
> On 1 Feb 2007 12:32:11 -0800, "Ozark Bicycle"
>
> >On Feb 1, 2:25 pm, Werehatrack <raul...@earthWEEDSlink.net> wrote:
> >> Oddly enough, the JIS headsets I've got here (two of them, but neither
> >> guaranteed to have what was supposed to be in them) both have cups
> >> whose head tube flange measures 30.2mm.
>
> >I think you may have something that is/was being sold as a "semi-JIS"
> >headset, i.e., ISO cups and a JIS crown race. These can be useful for
> >putting a JIS fork on an ISO frame.
>
> >> I suspect that they're
> >> probably quite malleable in that area, however; these are just Tange
> >> bottom-feeder quality. Or, at least, that's what's marked on the
> >> boxes.
>
> >Indeed, Tange is the brand I've seen on those "semi-JIS" headsets.
>
> That would explain it. Thanks; I'll re-mark them and set them aside.
>
> I still have to find a crown race to fit that blasted Rollfast.
What crown race ID does it need?