Need Help Identifying possible Sandy parts

[imabass]

Hello. I am new to the site. I have a couple 750 choppers. Yes, I understand that this maybe frowned upon of having sandy parts in a chopper but if i do its just dumb luck I suppose. I acquired a aftermarket frame and boxes of parts from my brother last year. It was a project that he started several years ago and never did anything with it. So i got the parts from him. I have been a member of some of the other 750 sites and no one could ever tell me much about the engine that I had other than it did not have a 836 kit in it. So I assembled it and ran it for about a year and I removed it when i took the bike apart for paint. When i had the engine out, I thought I would take the top end off for inspection. It was just this weekend when i realized that it had several differences then my stock 75. So I tore them both apart at the same time for comparison.

So typically the engines are easy to ID but I have one of those factory replacement cases with no #'s. I realize that the case is not a sandy but its the heads and jugs that I think are possibly from the sandcast days.

Here are some thumbs of the pics that I have noticed there are differences. I hope posting linked pics is OK here but i didn't see any forum rules (other than no copyrighted material)

Also, I noted several differences in the 2 sets of jugs that I had. See notes on the pic.




Here are some more pics of the comparison of the heads.


OK. I just got done cleaning up the heads and jugs. In the process i found a few more things out about





them. Here are some more pics of differences.





Thank you for your expertise. Oh yeah. In case you were wondering here is the bike its going back in.

[imabass]

I have been told that the fins are much thinner on the sandcast vs the diecast. The fins on the head are less than 2mm thick compared to my diecast engine of a little over 3mm.

[kp]

Imabass,
The unidentified head you have is a K0 69/70. Value would be $150 to $300. Need better quality pics to see if it's early or late K0. The early heads had differences in galleries and casting. You need to visit the website as there are articles on various part differences including heads. It's not exhaustive but will give you a start to identify what you have. KP
PS Can we ask your name as we like to the personal touch with the members. 

[imabass]

KP. Thanks for the response! I will try and look a little closer tonight. Is that the same production for the jugs as well?

My name is Will Bass, I am from Tulsa. I am also a moderator at the sohc750.net website which is a great place to hang out and find diecast parts. I realize that is not really what you you die hard sandcast guys are into but surely you have non sandcast 750's as well.

I am a huge fan of the 750's. They are a well oiled machine and the are fairly inexpensive to work on as long as its not sandcast. I wish I had the rest of the bike that these parts came from. When my brother bought the engine it was advertised as a 836. Seems that is a common thing with these older enigines as there is no way to verify unless you remove the head. I recall the first time i tore down the engine to the case and put it back together, i thought that I had missed some o rings in the assembly process because I had a handfull of them left over from the kit. Now that all makes sense.

Just curious. How long did the K0's run in the production #'s?

[Steve Swan]

Hi Will,

Welcome aboard ! We like ANYTHING sandcast !!

And, you are correct, i am sure most of us, if not all of us, like, and appreciate any sohc4 CB750. And of course there are sandcast/K0 members who own K1-onward sohc4's.

The "K0" production run was from vin 7415 to 44649.

[imabass]

Thanks Steve for the welcome!

According to the page at http://www.cb750sandcastonly.com/support09.htm this would be an early head because of

"I have included pictures of two specific head castings. The bottom (and cleaner) head casting is from my own VIN 1/7414, which I refer to as the earlier casting and the top shot is of a later casting.... Main differences are:
1. Later head has no casting depression between rear head bolts"

Mine clearly has these depressions in the head. See pic  unless someone else sees something else?

[imabass]

Thanks for the help with the ID. Its always nice to know what exactly you have. I will be sure and ride it as originally intended by the engineers. I actually think that i got a better deal than if it were a die cast 836. Makes my chop a little more unusual then the others. I do plan to get a 836 or 850 in it very soon. I did port the head already and I plan to get a hotter cam in there for a little more power. it ran very strong for the first 1000 miles that i put on it while i was trouble shooting the other demons that were in the bike.

here is a pic of the engine when it first came alive after years of sitting. Of course this was after the complete tear down. http://s118.photobucket.com/albums/o117/....victoria104.flv