Changes on K0

[sancastnorway]

I am starting to restore an 2/70 K0 with frame number CB750-1022139, and I am need to know some detal about some parts.

On what Serial number started the:
- HM300 mark on the exhaust?
- The white foam for the seat?
- The long Chain guard
- Ended the rear rolled rim?
- Ended the recessed ignitin switch
- Ended the wrinckle tank

On front fender, I have seen
- Double cutted With clamp for speedo cable
- Single cutted With clamp for speedo.
- And finally no cut on both ends-

On my CB7501018317, there is a wrinckle tank, double cut fender, recessed ignitin, read foam and rolled rim, unmarked mufflers, short chainguard, so the changes I am looking for is after this number.

I will preciate if someone have some answeer/Serial numbers on this to help me.
Jan

[Sgt.Pinback]

Hello Jan,

good questions, I dont have the answers but will give some thoughts:

- HM300: used on K1 as well, so your 22139 should have them (unless it´s a German/Dutch/French K0, then it should have "HMCB750"). "No number" only on early sandcast.
- white foam: never seen on K0.
- long chain guard: came with K1
- rolled rim: ending I dont know
- recessed ignition switch: ending dont know. My K0 (16xxx and 19xxx didnt have them, but they are German spec)
- wrinckle tank: my 19xxx has but my 16xxx had´nt. So my theory is: there were at least two suppliers for tanks, they started with the one who made wrinckles and then had another who made them without. So early bikes have wrinckles, then its mixed. Both my bikes were stock with original tanks

Front fender

- dont know when double cut was replaced to single cut. In any case it should have the hole for the cable clamp for your 22139

My 19xxx and 16xxx both have double cut with cable clamp hole



BTW: have a NOS "HM300" for sale

[hondasan]

Some answers for you:-
Long chainguard was first fitted from VIN 1021880 (according to parts list number 4 dated Sept. 10 1977)

Recessed switches were fitted to VIN 1024xxx that I know of, possibly a little later.

No. Number exhausts were fitted to all sandcast, and the first die casts, possibly until end of 1969 (so VIN approx. 1018xxx). My own early die cast 1008054 still has its original factory "No no." exhausts.

Hopefully others with original machines can add more info.

Chris R.

[honda mec]

Concur with the above re exhausts. Had a mid 16xxx vin with a build date of 12/69 which had no number exhausts.

[Don R]

 My 14,100 has a wrinkle tank and had a single cut fender. Heavily parts swapped with a k4 at some point. So the rest I can't say.

[kp]

My 14,100 has a wrinkle tank and had a single cut fender. Heavily parts swapped with a k4 at some point. So the rest I can't say.

Should have a double cut but as you say, many parts removed.

[Bruce Eastwood]

Dear all,

I'm able to buy a K0 with the frame serial # CB750 1007323.
Is this a real sandcast frame serial number or not?

Kind regards,

Bruce

[kp]

Looking at the VIN directory it certainly is in that sandcast frame number series given there are higher frame numbers that are fitted with sandcast engines. Nevertheless, the only way to determine the answer is to see what engine is fitted. Whilst the frame number is important, the determining factor as to sandcast status of those early to mid 7XXX frames are the engine cases original to the frame. Hope this helps

[Bruce Eastwood]

Thanks for your answer man!
Well, the engine has a serial number CB750E 11138555 which would be a K1 number I believe or a K0 die cast.

What is your personal opinion - worth buying or not?
Motorcycle is partially restored and the paint is the Honda brown color which is a K1 color ... engine has been overhauled
Price 10K UK pounds.

Bruce

[hondasan]

Too many digits in that engine number, but assuming the first two are correct (ie, 11xxxxx) then it is a very late 1971 K1 motor.
10K UK pounds sounds strong to me for a "mongrel".

Chris R.

[Bruce Eastwood]

Hey Hondasan,

CB750E-1113855 is the correct # ...

Bruce

[kp]

Agree with Chris. Lots of money for a "bitsa" Need to post a photo or 2 so we can see what's on the bike

[Bruce Eastwood]

Hey KP and Chris,

Appreciate your inputs - thanks.
I have seen the bike and know whats on it.

Frame is K0 sandcast thats it all the rest is K1 and in good shape (engine has been overhauled by pro)
How difficult is it to find an engine on the market with a serial number xxx6900 to 7414 in order to fit the frame number which is 7323 ?

Bruce

[kp]

Well if, as you say it's all K1 then it's worth no more than US$5000 and that's only because of the frame. A frameless late numbered K1 would be lucky to realise $2000 and reasonable K1 which is not original would be average $4k to $6k. Good original K1s are up to $10k. Pristine original or fully "bling" restored K1s may go to $13k.
Turning a sandcast frame into a reasonably correct sandcast bike means not only a "complete engine", but also a wrinkle tank, round rear rim, 2 hole rear hub, correct front rim, ducktail seat, double cut mudguard, side covers, correct airbox, correct instruments, correct carbs, correct exhaust and just these few items alone are expensive. Then you have other unique K0 features such as master cylinder, mirrors, battery box, forks, rear swingarm, oil tank, rear 2 hole mount mudguard, recessed switch and much more. That's another maybe $15,000+++ before anything else. It would be easier to get a K1 frame and turn that bike back to what it is and either sell it off or buy an early K0 and use it as a donor.
Others may disagree

[Bruce Eastwood]

Hi KP,

I absolutely agree.
I‘m considering buying a matching # K0 diecast year 1970    25325 number for frame and 25651 for the motor.
It seems to be original but run down.
I will restore it to original condition.

Or I wait, saving more $ and buy a run down K0 sandcast with a number below 7414.
But they all run in the 25-30k $ bracket...

Bruce