Topic: Diving head first into the Cafe racer "scene"(i have no idea what i am doing)

[Elan]

the head will also have a number on it. 300, 341, 392, 405, 410, etc.  It will be hard to see with it in the bike but possible. It is on the top fin center  on the carb side.

this will at least tell you the head year range. check it up to...

http://www.hondachopper.com/engine/engine_timeline/timeline.html

see pic below (pic credit goes to Jerry Griffin)



also, check if you have little rubber things between some of the fins. Those were removed at engine# CB750E-2228679 (between K3-4)
See this...

http://www.sohc4.net/cb750-faq/indexphp/cb750k-and-cb750-engine-differences

[GNGSXR]

Awesome thank you. I knew there was a stamp on the head but wasn't sure where exactly.
Mine is 300 and i do have little rubber things in between my fins. I am relieved to know that most of the bike is a '71.

My father owned a CB750 back when he was a in his early 20s and wrecked it. He sold it and the new owner replaced the case, gas tank and other cosmetic stuff. I wonder......

[Stev-o]

It's very common to have different parts on it, you may never know why.
You plan to cafe it, so no worries. 

[BeSeeingYou]

also, check if you have little rubber things between some of the fins. Those were removed at engine# CB750E-2228679 (between K3-4)
See this...

http://www.sohc4.net/cb750-faq/indexphp/cb750k-and-cb750-engine-differences

The list of changes may have a few minor errors......my 750F1 is as close to stock OEM as it could be and still has the little rubbers between the fins.  Engine #2529###

[laminaytrap]

May be a late F/ late K thing, my 77K had rubbers too.

Interesting build coming here, hope you have fun and stay on target!