M5x0.9 = unobtainium?

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What length M5x0.9? I can see if I can source them through our family business for you. Thanks Dan.
 
In the oval head [for the 45 J hooks, windshield hold downs, and the early heater inlet louvers] they only need to be 14mm long. In the slotted round head version for the SD40 carbs they would need to be 20mm long.

I could use about four dozen of each...just for personal use!

Subscribed.:)
 
Here in Australia, a lot of electrical panel builders and electrical tools use M5 screws. Not sure of the thread pitch - but perhaps check an electrical wholesaler in your area - they may keep some in stock.
 
Typically M5 is 0.8 thread pitch. Waiting to hear back from supplier on availability of 0.9 pitch.
 
During the restoration of my 68 40, I came across the same issue.
no source for m5x9

I solved the problem by drilling each m5x9 hole and tapping to m6x1.0.

Problem solved.
IMG_2454.jpg
 
Is that an old Case/IH in the background?

During the restoration of my 68 40, I came across the same issue.
no source for m5x9

I solved the problem by drilling each m5x9 hole and tapping to m6x1.0.

Problem solved.
 
Unfortunately I was unable to source the m5x0.9 screws. We could always have them made but I would need to do a minimum order of 5000 unfortunately. I will keep checking with other suppliers.
 
In the oval head [for the 45 J hooks, windshield hold downs, and the early heater inlet louvers] they only need to be 14mm long. In the slotted round head version for the SD40 carbs they would need to be 20mm long.

I could use about four dozen of each...just for personal use!

Subscribed.:)

I may be able to source these from Japan directly. Would you want them in stainless steel or cad-plated, or chrome, or?
 
Here you go. It's a thing old Jap motorcycles guys deal with a lot. Here's a Honda Service Bulletin from 1967.

TL #27
6/8/67

CHANGE OF THREADED PARTS

IMPORTANT!
In an effort to obtain more universal uniformity of threaded parts, the J.I.S. (Japan Industrial Standards) threaded parts standards have been modified to conform with those established by I.S.O. (International Standards Organization). All Japanese industry, including Honda Motor Co., is cooperating in this change. Although the modifications of the present J.I.S. system are not extensive, this change will require some new tools, different tool applications, and will introduce the possibility of non-interchangeability of similar parts.

This change-over will be effective from the start of production of all new motorcycle models first produced after the beginning of 1967. In all other models, those previously in production, the change-over will be made gradually and on no set schedule.

The following will describe the modifications and the effect they will have at the dealer level:

  1. Change in Thread Form -- The minor diameter of internal threads will be decreased slightly in all sizes. This change is very minor and will not affect interchangeability in any way.
  2. Height of Bolt Heads -- There will be minor changes to the height (thickness) of bolt heads in several sizes. These changes will not affect interchangeability.
  3. Thickness of Nuts -- The thickness of both common and thin nuts will be reduced in sizes 8 mm and smaller. These changes will not affect interchangeability.
  4. Width Across Flats of Bolts and Nuts - - The width across the flats of the hex (the wrench size) is changed for all nuts and bolts except 6 mm.
Normal Dia.Width Across Flats (Wrench Size)
(Size of Bolt or Nut)Present J.I.S.Modified J.I.S. (I.S.O)

3 mm6 mm5.5 mm
4 mm8 mm7 mm
5 mm9 mm8 mm
6 mm10 mm10 mm
8 mm14 mm12 mm
10 mm17 mm14 mm
12 mm19 mm17 mm
14 mm21 mm19 mm
16 mm23 mm22 mm
18 mm26 mm24 mm
20 mm29 mm27 mm
New wrenches in the 5.5 mm, 7 mm, 12 mm, 22 mm, 24 mm and 27 mm sizes will be required for the modified bolts and nuts. All other sizes are currently in use.
This change in hex size affects only the wrench sizes; interchangeability of bolts and nuts is not affected.

Change in Thread Pitch -- The standard thread pitches for all bolts, nuts, and screws in the 3 mm, 4mm, 5 mm and 12 mm sizes are changed as indicated below:

Normal Dia.Thread Pitch
(Size of Bolt or Nut)Present J.I.S.Modified J.I.S. (I.S.O)

3 mm0.60.5
4 mm0.750.7
5 mm0.90.8
12 mm1.51.25
These changes will affect the interchangeability of threaded parts in these sizes.
Care must be taken to use the correct pitch to avoid stripping.

These changes will also require new taps and dies.

New tools, where required, will be available through parts department.

To help avoid confusion in the 3 mm, 4 mm, 5 mm and 12 mm size, wherein the thread pitch has been changed, the modified J.I.S. (I.S.0.) threaded parts used by Honda will be marked such that they can be readily identified. The marks used are as follows:

Part TypeDescription of Marking
Std. Hex BoltA number, indicating the strength of the bolt, will be embossed on the top of the bolt head. This mark will appear on modified J.I.S. (I.S.0 .) bolts of all sizes, but as explained above all sizes except 4 mm, 5 mm, and 12 mm (there are no 3 mm hex bolts) will interchange with the present J.I.S. parts.
Slotted Hex BoltThere will be a hemispherical embossment (bump) on the top of the bolt head in the 4 mm and 5 mm sizes (3 mm and 12 mm slotted hex bolts are not in use).
Cap BoltThere will be a hemispherical dimple on the side of the bolt head in the 4 mm, 5mm and 12mm sizes (3 mm not in use).
Stud BoltThere will be a hemispherical dimple or embossment on the nut end in the 5 mm and 12 mm sizes (3 mm and 4 rom studs are not in use).
All Cross Recess ScrewsThere will be a hemispherical embossment on the top of the screw head in the 3 mm, 4 mm and 5 mm sizes (12 mm not used).
All NutsThere will be a hemispherical dimple on either the top or side of the nut in all sizes with changed pitch. This will also apply to nuts that are permanently welded to other parts.
All mechanics and parts department personnel should read and understand this bulletin, to avoid confusion and damage to threaded parts when the change-over occurs.

Additional information relative to these changes part numbers, tool numbers, etc. will be published by parts department.

AMERICAN HONDA MOTOR CO., INC.
Service Department

9-325
 
Thanks for verifying what I said--1967 was the changeover date in Japan.
Still looking for a fair and reliable source for the JIS M3-M5 for the early trucks.
 
I ended up ordering a bunch from that guy. Wasn't cheap, took awhile for overseas shipping. Thought I'd put them on eBay so they'd be available in the US, but got lazy, so they're sitting on a shelf still.

If you need em, send me a private message or email..... update.... they're all sold. I have no more.
 
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Thread revival:

I am in desperate need of one m5x0.90 hex nut for my ammeter post. My manufacture date is mid 1966. I have double checked the thread pitch, and the original nut has been destroyed by a previously loose connection.

Anybody have a source?
 

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