Topic: CB650 Cylinder Head Bolts

[danderso]

Hello everyone!

I've been trying to piece together a 1980 CB650 for the past two months, and I have been unable to find some cylinder head bolts; or maybe I have gotten the correct ones, and lack the intelligence to get this thing together correctly! 

Does anyone know the dimensions and specifications of said bolts?



I believe they're Number 8 & 9.
I can post a picture of the hardware I have gathered so far, and post it.

[scunny]

10  flange head bolts at 120mm long
 2   flange head bolts at 145mm long
I forget if the 2 long ones are front either side of cam chain tunnel or rear of motor.
be very careful when reassembling that the cam chain tensioner bottom is sitting in the wee pocket for it, you can see and feel this with the sump pan off.

[danderso]

10  flange head bolts at 120mm long
 2   flange head bolts at 145mm long
I forget if the 2 long ones are front either side of cam chain tunnel or rear of motor.
be very careful when reassembling that the cam chain tensioner bottom is sitting in the wee pocket for it, you can see and feel this with the sump pan off.

Thank you! I believe that the longer bolts sit towards the intake side, it appears that their perches are slightly higher than the rest!

[danderso]

Do you know the thread pitch by any chance? I'm considering going to Fastenal and seeing if they have anything that I can use!

[cb650]

I have some  we can pull for samples.    Next Saturday is best.

[danderso]

I have some  we can pull for samples.    Next Saturday is best.

Sounds good Terry, I'll shoot you a PM towards the end of the week

[danderso]

Excuse my "fantastic" handwriting haha
Do any of these bolts look correct?

From left to right:
(grey bolts)
145mm
100mm

(black bolts)
85mm
100mm
130mm

(washer)
Outside diameter of 20mm

-And just to clarify, I was measuring from under the bolt head to the very bottom!

Thanks,

Dan

[danderso]

Can anyone tell if any of these bolts are correct? If so, I might be able to go down to Fastenal and get some "new" ones

[RJ CB450]

Hrm... I am trying to sed it clear on phone.  Three on right are head bolts.  Note the crown how it is wider.  This is important for both keeping aligned and preventing head deformation when torquing down.  In addition, bolt grade is important.  It isnt just a matter of thread.

I did my head last year, cannot remember exactly the bolts in head plus 82 is different iirc...

[cb650]

Bring what you got and we can pull some out of my motor and be sure.
Here is a thread on the 650 site someone is tearing down a 650 and pics of the bolts.
http://www.hondacb650.com/viewtopic.php?f=4&t=10018&p=70012#p70012