Need a source for pre-1967 JIS thread pitch screws.

[G-Man]

Quite often, with the longer bolts and screws, Honda rolled the threads into the material rather than cutting them. This means that the bolt shank is too small a diameter to cut a suitable thread into.

I prefer helicoiling the holes (where possible) and the problem goes away....






G

If you drill down on the individual item spec on Mc Master Carr, it shows .8 pitch for the 5mm screws, so just because they say JIS, doesn't mean "old" JIS.

Evidently, JIS still lives on even though it adopted some (or all?) of the ISO standards in '67.

I have ordered honda part numbers for old JIS screws from honda dealers and received screws marked with the correct part #, but with "new" thread pitch, and no superseded number

You're right about this. In the Honda Service Bulletin that covers the change they refer to new and old JIS. Usually we want fasteners made to the old standard.

As an aside, I have a tap and die set that covers all of the old thread pitches. If I could find screws that haven't been threaded, I could cut my own as needed. Does anyone know of a source for such a thing?

Maybe obtain some longer length shoulder screws and cut the threaded portion off?

[Tim Allman]

Quite often, with the longer bolts and screws, Honda rolled the threads into the material rather than cutting them. This means that the bolt shank is too small a diameter to cut a suitable thread into.

I prefer helicoiling the holes (where possible) and the problem goes away....

That's only a partial solution however. For instance, 8 mm cap screw heads and nuts have 14 mm flats in the old JIS style. The modern thread pitch is still 1.25 mm but the flats are 12 mm. Admittedly this is mostly an aesthetic issue but, well, they just don't look right.

[G-Man]

Tim

Much easier to deal with the hex screws and bolts as they are :

a) easier to identify
b) easier to buy in reasonable condition (I just buy job lots of Honda bolts from eBay sellers)
c) Not so hard to make or get them made. Get some 14mm hex stock and you are almost there.

Just my two cents......

G

Quite often, with the longer bolts and screws, Honda rolled the threads into the material rather than cutting them. This means that the bolt shank is too small a diameter to cut a suitable thread into.

I prefer helicoiling the holes (where possible) and the problem goes away....

That's only a partial solution however. For instance, 8 mm cap screw heads and nuts have 14 mm flats in the old JIS style. The modern thread pitch is still 1.25 mm but the flats are 12 mm. Admittedly this is mostly an aesthetic issue but, well, they just don't look right.

[jnbmoore]

Seadog,

Those screws were pricey but being NOS, they worked. Thanks!

[jnbmoore]

Seadog,

Those screws were pricey but being NOS, they worked. Thanks!

[Seadog]

Good; glad to have been able to help.

Seadog,

Those screws were pricey but being NOS, they worked. Thanks!