Author Topic: 77 CB750k head on 76 CB750K engine?  (Read 486 times)

0 Members and 1 Guest are viewing this topic.

Pushboater

  • Guest
77 CB750k head on 76 CB750K engine?
« on: April 25, 2010, 02:11:36 AM »
I need to replace the head on my 76 CB750K and have found a good deal on a 77 CB750K head.  Will the 77 head work on the 76 engine and if so are any modifications required?

Online Jerry Rxman Griffin aka MuthaF'er

  • This MuthaF'er is getting to be a
  • Really Old Timer ...
  • *******
  • Posts: 14,914
  • Bought her new 4/75
Re: 77 CB750k head on 76 CB750K engine?
« Reply #1 on: April 25, 2010, 08:39:48 AM »
It'll work fine and maybe even a little better with the updated combustion chamber design. No mods necessary. If you look on the top rear fin by #3 intake you should see a 392 which will ID that head as a 75/76F or 77K. My K8 head also has 392 but with an added hand stamped K8 next to the 392. This apparently lets us know it has the different keeper/spring system of the F2/F3. You may even get a compression bump too. The later engines had 9.2:1 ratio. It has been said that was due to pistons but I have seen both piston designs in these 9.2:1 engines leading me to think it is possibly due to the hemi design head alone. I'd really believe this theory if we had someone cc both heads.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)