750k motor

[gooch]

Hey guys, I am going to need a motor for my 78. it has started leaking and I think I may be better off with another motor versus rebuild. anyone know of or have anything? I am in Illinois.

Thanks
Jim

[TOOLS1]

If your engine is only "leaking" just replace the gasket/seal. The only reason to rebuild an engine is if it does not have compression, or is broken internally. Also any 40 year old replacement engine is probably going to at least need new gaskets/seals, so you would not be gaining anything. However let me take a guess as to where it's leaking from. the fins between the head, and cylinder, and the valve cover.
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[gooch]

Tools,
Its worse than that. It is also leaking from the base gasket right above the points cover. Im afraid the cylinder could possibly be warped, Best case is I suppose the gasket could just be bad there

[TOOLS1]

If it were my engine I would just go on and do a top end rebuild. Rings, valves, cam chain, cam chain tensioners, gaskets, and seals. Would cost around $300.00 for parts (Cycle-X, and Vintagecb750 have good deals on parts) and $60.00 for the valve job. You can easily do the rest. Then you will have a fresh like new engine. For about $300.00 more you could go to 836cc.
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[Lucky 1]

IF you get another engine you will just have another 40 year old engine with the same problems.
No matter how many miles are on it . It is still 40 years old.
The 1978 engine had the most improvements of all of the 1978 engines.

If you keep YOUR engine and rebuild it, you will know EXACTLY what it has. It will be new.

If you rebuild  you will not have 40 year old dried up hardened valve guide seals.
you will not have dried up crumbling cam chain rollers with bits of rubber
inside the crank oil journals. You will not have leaking cylinder head pucks and oil seals.

You will not have old worn out valve guides.

Rebuild what you have instead of rebuilding some one else's mess.
Then the serial numbers will still match.

If you do not want to rebuild it send it to Cycle Exchange for a rebuild instead of wasting that same money on a used unknown engine with 40 year old dried up crumbling parts in it.
Even if it has low miles it is still 40 years old.

I know you just want to get a bubble wrapped package with a new engine and pop it in the frame don't you.  LOL...lol...NOT GOING TO HAPPEN.

[gooch]

Here is my situation with this bike, I have three 78 750k's. I am going to sell this one but I dont want to sell it leaking to someone. If I sink 500.00 to a 1000.00 into I couldnt afford to sell it. Its been my experiance that once you have them apart you start with rings and gaskets, then heck while its a apart why not do the valves, then seals, then hope that it doesnt need guides, etc. then at this age probably cam chain and tensioner, Then I still have the possibility of a warped cylinder.
Thats why i was entertaining the idea of a used, running, non leaking motor. unless someone wants to make me an offer on it as is and save me the trouble.

Thanks
Jim

[Lucky 1]

I seriously doubt the cylinder is warped.
Very unlikely.

Just sell it as a complete running bike that needs work.
Then use that money to build yourself a good engine.


There ARE used engines, but almost every single one needs to be completely rebuilt
because they are all 40 years old. See what I mean?


ALSO: when an engine is out of the frame and
 all apart IS the time to take care of EVERYTHING .

You will have ALL WINTER LONG to do it and pay for it.

Then next summer you will have a brand new engine that needs nothing.
And if you sell the bike, you can sell it much easier when you
can tell the new owner that it did not have just a half a$$ed top end rebuild,
 but was completely rebuilt correctly.

[gooch]

I dont need motors for my other bikes, they are in excellent condition. One of them I bought new in 77.
I just need to get the leaks fixed as cheap as possible so I can sell this one. If I cant find a decent used motor then yes I may have to pull the top end apart. I appreciate the rebuild advice but to be honest with you I have 13 motorcycles and that leaves me with plenty of things to work on in the winter LOL. So to get back with my original question,
Does anyone have a decent used motor or know where I can find one?

Thanks
Jim

[Lucky 1]

If I was buying a used bike I would much rather have the original engine and bike still in tact,
 than to have a replacement engine in it. That is just me.


Good luck on finding your used engine.

[TOOLS1]

Lucky 1 wrote

If I was buying a used bike I would much rather have the original engine and bike still in tact,
 than to have a replacement engine in it. That is just me.


Good luck on finding your used engine.

Ditto.
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[motogrady]

A guy has one, here in WVA, brand new, maybe an hour from me, puts it in the paper
maybe once a month.  All I know is it's a SOHC, and he want's 900 for it.
Since you're in it for the money, I'll take 100 for me, total would be a grand and you pick up.

If yer still interested, I can try tracking it down for ya.

[gooch]

Thats quite a drive to WVA. too bad im not going that way for anything, It would be a nice trip, I understand its really nice country where your at. I appreciate you looking for me though.

Jim

[Lucky 1]

Almost all of the Honda CB750 engines need to be rebuilt.
If there are any out there they are in use.
I cannot imagine someone rebuilding an engine and just letting it sit, waiting
for a new owner except one place..

Cycle X.  They will sell you an engine if you ship them yours.
Call Ken at Cycle Exchange and ask.

[TOOLS1]

Cycle-X is no longer doing engine re-builds. Only machine work.
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[Lucky 1]

Are you sure Cycle-X is not building engines?

[TOOLS1]

They have it posted on their site, and have sold all the engines that were in stock.
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