How do I measure my headset

[stephenmarklay]

I want a new headset for my 1990 Schwinn hybrid. How do I measure it (JIS or ISO).

I am guessing I need to take it out first?

[ultraman6970]

yes.

[Rob1519]

See if this works

http://www.canecreek.com/headset-fit-finder

[bikinchris]

I want a new headset for my 1990 Schwinn hybrid. How do I measure it (JIS or ISO).

I am guessing I need to take it out first?

A really good shop would order a ISO headset and cut the crown race seat if it is the JIS size.

[ultraman6970]

Remove the fork and measure the neck right over the crownrace, that will give you a clue w/o removing the whole thing, hoping you have no mixed stuff tho.

The other thing you can do is to move one of cups out a few mm and measure.

For the record would not surprise me that the bike was made in japan.

[charliedid]

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