1987 Specialized Crossroads threaded headset specs?
08-10-20, 09:06 AM
#1
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1987 Specialized Crossroads threaded headset specs?
I've got a 1987 Specialized Crossroads and the threaded headset needs replacing. Does anyone know the inside diameter of the head tube?
Would like to order the headset bearings before I source the tools to re & re.
Thanks in advance
Would like to order the headset bearings before I source the tools to re & re.
Thanks in advance
08-10-20, 10:15 AM
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While I don't know the specs of that model, this thread may help to figure it out. Also, the stack height is very important.
https://www.bikeforums.net/bicycle-m...dset-size.html
John
https://www.bikeforums.net/bicycle-m...dset-size.html
John
08-10-20, 02:20 PM
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Chances are it's either ISO 30.2mm or JIS 30.0mm; you can't really tell until you pull the cups and measure. A JIS spec frame and fork can easily be milled to ISO spec, but not vice versa. The path of least resistance might be to order an ISO headset with the same or shorter stack height as the original, and then deal with any mismatch when you get the old headset out.
08-12-20, 05:27 AM
#4
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Thanks guys.
Just got the bottom cup off 29.9 mm inside head tube. Cup reads 30. mm.
Just got the bottom cup off 29.9 mm inside head tube. Cup reads 30. mm.
Last edited by Dsprok; 08-12-20 at 09:51 AM. Reason: clarity
08-12-20, 06:09 AM
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That's JIS spec. Have you measured the ID of the crown race? is it also JIS (27.0mm) and not ISO (26.4mm)?
JIS headsets are readily available. You need to find a replacement headset with the same or lower overall stack height.
JIS headsets are readily available. You need to find a replacement headset with the same or lower overall stack height.
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08-12-20, 06:37 AM
#6
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Thank You, I will be washing up now. Then ordering on Amazon Prime a JIS Headset
08-12-20, 10:31 AM
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If the bike has a replacement fork, the only way to be sure of the headset specifications would be to do what you have done, taking measurements.
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