New Case Halves? ( 69Hnd754)

1969 Honda 750-Four
I have this bike sitting in my parents barn and I'm not the original owner.
I was hoping someone could tell me what to expect to pay for case halves,
what type to get? The chain slapped or
apparently broke and popped a hole (half dollar size) in the casing. I've
been told that Honda came out with a fix for this, does anyone know anything
about this issue?
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address.

Thanx

 

I'm not the original owner. I was hoping someone could tell me what to
expect to pay for case halves, what type to get? The chain slapped or
apparently broke and popped a hole (half dollar size) in the casing.
I've been told that Honda came out with a fix for this, does anyone
know anything about this issue?

Google for "Mr. CB750". It has links to sites that sell new old stock
parts...

"Mr. CB750" is an online magazine article about a guy who will build
you a brand-new 1969 CB-750K0 with new old stock sand cast crankcases
for only $22.5K USD...

Can you imagine anybody being that fanatical about K-Zero's that they
would fork out that much money for a bike with the fragile,
unrepairable sand cast cases that would be ruined if the chain broke?

Well, that kind of K-zero enthusiast probably would only ride the
bike once or twice a year, if that, keep it with his collection that
would include a Norton Commando, a Velocette, a Moto Guzzi and a
bevel-drive Ducati...

The "fix" for crankcase breakage was to replace the sand cast cases
with less brittle pressure cast cases...

But I think it would be a lot of work to tear down an old 1969 motor
to replace the cases and it just wouldn't make a lot of sense to
reduce the value of a 1969 K-Zero that some collector might want for
the frame #. I saw where a guy in England had a set of K-zero cases for
100 pounds sterling...

I know a guy who was advised to hold off buying a CB750 until the 1971
model came out. He still has that 1971 CB-750...

 

Good Mornin' Krusty,
Thanks for your reply and the info. What did you mean when you said:
" it just wouldn't make a lot of sense to reduce the value of a 1969
K-Zero"? Are you saying this bike has some intrinsic collectable value
and if so, how would I be reducing the value by repairing it? Do I also
understand that you feel the bike is not worth repairing"? I'm not a
collector, I'm just a guy who could use some cheaper transportation and
one who doesn't mind an occasional challenge as long as it's do-able and
doesn't require a break-in at Fort Knox.

Good Mornin' Krusty,
Thanks for your reply and the info. What did you mean when you said:
" it just wouldn't make a lot of sense to reduce the value of a 1969
K-Zero"? Are you saying this bike has some intrinsic collectable value
and if so, how would I be reducing the value by repairing it? Do I also
understand that you feel the bike is not worth repairing"? I'm not a
collector, I'm just a guy who could use some cheaper transportation and
one who doesn't mind an occasional challenge as long as it's do-able and
doesn't require a break-in at Fort Knox.

Rico

 

Wrong. The pressure cast cases would shatter if a chain broke. Honda did
two things. First they put a silly little chain guard which would have
done little, but then they made an endless or staked chain. Before then,
all chains had master links. Honda 750 K1 was the first bike with a
staked chain or the hp to need it.

-paul

 

did two things. First they put a silly little chain guard which would
have done little, but then they made an endless or staked chain. Before
then, all chains had master links. Honda 750 K1 was the first bike with
a staked chain or the hp to need it.

Yes, I know about the "band-aid" chain guard, but how do you repair a
broken sand cast crankcase? Honda replaced the broken sand cast cases
with new pressure cast cases...

 

" it just wouldn't make a lot of sense to reduce the value of a 1969
K-Zero"? Are you saying this bike has some intrinsic collectable
value and if so, how would I be reducing the value by repairing it?

Yes, the K-Zero is a collectible motorcycle. Your K-Zero may be worth
more than you think to a collector. Only 7000 were made with
the rough-looking sand-cast crankcases, and you might want to check
your frame number and engine number to see if they match. A set of
pressure-cast crankcases might reduce the value of your bike. Maybe you
could put it on e-Bay, as is, and see if you can get $1500 for it?

I'm not a collector, I'm just a guy who could use some cheaper
transportation and one who doesn't mind an occasional challenge as long
as it's do-able and doesn't require a break-in at Fort Knox.

I know your situation, was born there, and am still there. Only you
know what your time is worth and how much of it you can afford to spend
working on a 36 year old Honda four when you might be able to get
something that's only 20 years old for about $1500...

An alternative to rebuilding the motor with the broken cases would be
to find a later model engine with the 5-speed transmission. I'm sure
you can find them for a few hundred $...

 

How will the latter suggestion affect the value of the bike? I realize this
isn't a job (resurrecting the entire bike) that can be done in a weekend ,
and I don't really need it for transportation, I just thought it would make
a nice alternative especially in the warmer seasons of the year. I was a
recreational biker once, "back in the day", had a 450 Honda and a Triumph
Bonnnie. I guess I sorta yearn for the days of yester-year.

 

How will the latter suggestion affect the value of the bike? I realize this
isn't a job (resurrecting the entire bike) that can be done in a weekend ,
and I don't really need it for transportation, I just thought it would make
a nice alternative especially in the warmer seasons of the year.[/QUOTE]


The value in a collectible item depends on many factors, but two of the
most important to start are:
1. original condition, no matter how ratty it looks, an original paint
job is better than a re-paint. Same with other things-a rusty original
fender is better than a clean aftermarket one.

2. matching numbers on engine and frame

I'd take Krusty's advice to see how much interest you can get for the K0
in it's current condition. Do some research in places where people who
collect these things before you announce that you've got one for sale at
$XXX. If you can get more than say, $1000, you can probably buy a newer,
nicer bike that will be easier to fix up.

 

realize this isn't a job (resurrecting the entire bike) that can be
done in a weekend , and I don't really need it for transportation, I
just thought it would make a nice alternative especially in the warmer
seasons of the year. I was a recreational biker once, "back in the
day", had a 450 Honda and a Triumph Bonnnie. I guess I sorta yearn for
the days of yester-year.

It depends upon how original your K-Zero is, if that is what you have.
Putting a later model engine into a cherry K-Zero might seem like a
heresy to some, but, if you don't care about that and you're just going
to putt around on a resurrected old Honda, and you won't be in the
position of being late for work or missing college classes, it's just a
Sunday toy and it really doesn't matter...

If I was going to restore an old Japanese bike of that era, I would do
a Kawasaki Z-1, or a Suzuki GT-750 water buffalo. Both of those bikes
had bullt-proof engines. The Honda 4's were always built as
economically as possible, but the Z-1 I mentioned, and the Suzuki were
built like brick shithouses, they were really engineering overkill. And
the Suzuki GS-750/1000/1100 series were built fairly strong, too, they
make reliable toys if you replace the alternators with aftermarket
parts...

 

Thanks for your input John, I'll look into it.

 

parts...

Thanks KK, I wasn't really looking for a project, this Honda is in the here
and now and I thought it might be fun and interesting to see if I could get
it going. It would only become primary transportation after a significant
"sea trial"
period. But generally, if it's not cost prohibitive it will serve mostly for
Sunday rides and short excursions.

 

the sand cases were only a stop gap production. When the bike was a hit,
sand casting was too slow. A case pressure cast will not stand up to a
broken chain any more than the sand cast ones did.

I guess those old K0's with sand cases are prized by collectors now.

Oh, btw, many sand cases were replaced by Honda as some were porous.

-paul

 

OK, I haven't seen one of these in many years, but AFAIK, that
extenstion to the case is just a shield to prevent chain lube fling and
give the bike the finished look the Japanese demand. So if I'm
remembering rightly, you can ride w/o that piece in place.

I think at least you need to dismount the carbs and give them a full on
cleaning. I'd also check the points and replace them spark plugs, etc.
Drain and flush the fuel tank - in other words re-commission the bike
wholly. I'm sure you can find workshop manuals on this bike easily new
or used. Be SURE to get a manual which covers your model.

Again, going from dim memory, K0's were before Honda got the idea to do
a bar connection for the carbs so the carb synch is a bit more complex
than on the later models. You will need a set of carb stix or hire the
job out to get the carbs working properly.

Compared to today's bikes, this bike is stone simple. I think you'll
find it a satisfactory ride.

-paul

 

The cases can be welded by a competent welder. Competent welders are as rare
as honest lawyers, however. Depending on where the hole is, plastic steel
may be a better fix.

However, since this bike is very collectible (means some nuts will pay many
times what it is worth) , especially in it's apparently 'barn-fresh'
,un-f***ed-with condition, sell it! Then use the money to buy a nice,
non-collectible, bike that you can RIDE! btw the problem with chains piling
up on any bike is caused by lack of maintenance and/or cheap owners
replacing their chain with bulk machine chain from the hardware store.

Hank

Soichiro disciple for 30 yrs, former Honda parts/service guy.

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interesting, i'd never heard of that fix. the problems we in the northeast
areas had was cheapskates
who wouldn't keep a good chain in the bike would have a chain break and
take out the area around the sprockets.
i've fixed a few of these. i've done a couple of bore jobs using 350 twin
o/s pistons and yosh cams and the bikes
were spectacular (for the times). i've still got a pair of webers and
manifold for them. i just can't bring myself to
can them.<G>
for a near permanent fix, the epoxy route was ok if not best.
i'm talking about the single cammers.
sammmmm

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