6mm Screws... DIN or JIS ??

GeorgeP1111 · Post by **GeorgeP1111** » Fri Feb 04, 2011 6:27 pm

I'm getting a list of nuts, bolts, screws and so on that I need for putting my CA77 motor back together. I'm looking at 6mm Diameter 1mm Pitch Pan Head screws in McMaster-Carr and I see that they list both DIN and JIS for the same screw. Big difference in price, take a 6x20 in DIN is $9.25 per 100 and the JIS $10.15 per 25. I'm assuming we're talking about pitch here? I did search postings here for which one we use, but only found two posts and neither were very clear to me.

I'm going to order long Pan Heads and cut them to the various lengths I need, and for the case screws I'm going to order threaded rod and acorn nuts.

http://www.mcmaster.com/#machine-screw- ... rs/=aw41xl

So which do I look for, DIN or JIS?

tnx
George

teazer · Post by **teazer** » Fri Feb 04, 2011 8:00 pm

In smaller sizes there's a pitch difference as well, but IIRC the real difference is thread angle.

I use regular old 6mm ISO threads in all my bikes and never had a problem.

brewsky · Post by **brewsky** » Fri Feb 04, 2011 8:16 pm

I would look for JIS or ISO.

The only sizes with pitch differences are 3, 4, 5, and 12mm nominal diameter.

All the others should interchange, old with new, except the head sizes are smaller in most cases for bolts.

It does get confusing, as old JIS does not necessarily equal new JIS, which is also referred to as ISO.

I believe the current DIN pitch is different from the current JIS for 6mm size.

The Honda Parts Catalog has a section in the beginning explaining which changed and how.

GeorgeP1111 · Post by **GeorgeP1111** » Fri Feb 04, 2011 10:14 pm

brewsky wrote:I believe the current DIN pitch is different from the current JIS for 6mm size.

I checked the URL I had listed and saw that it did not go to the page I had intended... sorry about that. Here is what was on the page I was talking about:

20 mm Deutsche Industrie Normen (DIN) 92005A428 9.25 per Pack of 100
20 mm Japanese Industrial Standards (JIS) 94387A429 10.15 per Pack of 25

These are my two choices for a 6mm Pan Head screw, 20mm in length with a 1mm pitch. So the when given these choices, the JIS would be the ones to get? I did buy some screws from my local hardware store but they were simply listed as 6mm, no DIN or JIS, and they did fit fine.

JIS the way to go?

tnx
George

rrietman · Post by **rrietman** » Sat Feb 05, 2011 12:43 am

George; do the pan head screws you are looking at have the correct head diameter? I've been buying "Motorcycle America" blister packs of screws that are correct but Terry at Retro Bikes has run out of them.
Thanks
Randy

e3steve · Post by **e3steve** » Sat Feb 05, 2011 5:23 am

George, ISO (International Standards Organisation -- international except North America!) machine screws & bolts (partially threaded) are a perfect M6 & M8 fit.

brewsky · Post by **brewsky** » Sat Feb 05, 2011 7:35 am

brewsky wrote:
I believe the current DIN pitch is different from the current JIS for 6mm size.

I got that part wrong.
The pitch is the same, it is the head dimensions that are different.
If you look at the individual drawings for each, the JIS heads are slightly smaller diameter and thinner than the DIN.

Steve is right.....partially threaded, ISO (or Current JIS) would be best, but I've only been able to find the partially threaded in hex head so far.