Bolts #9 #10

[Joe K]

Hello,

Does anyone know if there is any significance of the #9 and or #10 bolts?  I have several of each as well as one S bolt. 

Thank you,
Joe K.

[kp]

Joe, I'm probably totally off target here but I understood these numbers were indicators of the grading of the bolt. As we all know the international marking for fasteners is generally by way of lines on the head of the bolt but seems these early Japanese fasteners had other identification marks. Certainly numbered bolts are a feature of many Japanese manufacturers, and some still used (head) numbered fasteners in production. Can anyone else add their thoughts or knowledge as Joe has asked a good question and I'm also intrigued.  KP

[cb7504]

Joe:
     Can you post a picture of the bolts, clearly showing the number on the bolt head and thread size. Marty K.

[Joe K]

It is really hard to get a photo of the bolt heads with my camera's flash and focus.  Anyway, I did the best I could and attached are just a couple of photo's.

Joe K.

[kp]

So Fellas, anyone got some info to offer  KP

[Steve Swan]

I've seen these 9/10 bolts on other earlier Japanese motorcycles, cannot remember on what or when, has not been too terribly long ago, they are not sandcast and i am thinking not Honda.

[Joe K]

Then they must have come from some other parts I received from somewhere along my restoration past.  I sorted all my bolts and saw these and thought that maybe they were rare sandcast, but they must not be.  Thank you for your help.

Joe K.

[Steve Swan]

Chris should weigh in on this

[kp]

The #9 bolts are off CB750 cam assemblies.

[hondasan]

#9 bolts were indeed fitted to the cam tower assemblies. The other are I suspect not original CB750 fitment.

[Joe K]

My engine 4646 cam tower had #8 bolts on it.  Does anyone know when the #9 bolts came in the production process?

Joe K.

[kp]

My book shows a change at engine number 26144. Not sure if this is it but I have a K1 engine that has #9 heads. I'm intrigued about the #10 bolts though    KP