Topic: '73 cb750- what engines will go in this frame?

[Aatrain]

I have started rebuilding my 73 and its needing a completely new engine. Too much broken off / seized up, etc. What years would drop into this frame? Im planning on finding another donor bike (for other parts as well) but engine fit is my main concern...

[Alan F.]

All single cam CB750 engines from 69-78 will bolt right in.  There are distinct differences between the 69-76 engines and the 77-78 engines that can be easily overcome by swapping out a few other parts, essentially 69-76 should bolt in and go. 750A engines are a no go for K/F engine replacement.

You'll get plenty of good info from members who've been there.
Alan

[Aatrain]

Thanks. I'm seeing alot of 78's around - I might investigate that route. What can I expect to have to change?

[the technological J]

where are u located i have a 73 engine for sale its in peices tho

[Aatrain]

I'm in central Texas- pm me a price and pics if you're close

[the technological J]

i had another member from texas interested it was gonna be around 500 shipped at the best rate i could find

[Aatrain]

Will keep you in mind, but to be honest with you, Im hoping to get another complete donor bike for other parts as well. This bike is going to need ALOT of stuff. Really the only reason I'm even taking it on it pure sentiment. But I don't care so much as to do it as a restore- will be a chopper project- so the year of the engine is secondary to fit and total cost for me.

[the technological J]

no worries i wouldnt pay that for an engine  either... but just throwing it out there