JIS screws

kawonda750 · Post by **kawonda750** » Thu Jan 25, 2018 7:43 pm

I am looking at case screws and am told that they are JIS. I have been restoring Kawasaki triples for years and can get stainless case bolt sets easily. In looking at bolt suppliers on the web, they show JIS as being a different sized head but with standard M threads. Is this correct? Can I use M threads maybe with hex heads?

rrietman · Post by **rrietman** » Fri Jan 26, 2018 12:42 am

yes and yes. you want the right ones go to McMaster Carr for JIS head screws. you want the wrong ones any old 6mm will do.
Good luck
Randy

jkv357 · Post by **jkv357** » Fri Jan 26, 2018 9:27 am

I believe there was a time that Honda used JIS screws with a now non-standard thread pitch, so depending on the year an original 6mm JIS screw may not match a current M6's pitch.

Anyone know anything about that?

Tim Allman · Post by **Tim Allman** » Fri Jan 26, 2018 9:46 am

jkv357 wrote:I believe there was a time that Honda used JIS screws with a now non-standard thread pitch, so depending on the year an original 6mm JIS screw may not match a current M6's pitch.

Anyone know anything about that?

The change to ISO happened in the late 60s. Several screw sizes were affected but not the 6 mm ones because the two standards are essentially the same. So, any current 6 mm screws will work.

JoeM · Post by **JoeM** » Thu Feb 22, 2018 12:25 pm

I tackled the whole JIS issue some years ago. Further discussions here

https://fourwheelforum.com/showthread.php?t=1924