SOHC.co.uk Forums > CB750

Bought me a money pit ?

(1/4) > >>

Grewth:
I really don't know what possessed me, but I bought this K6 a few days ago.
It's provenance is proving to be somewhat interesting.
Most of the bike seems to be K6, but the tank, carbs, swing arm, and instruments would appear to be off a K2.
The exhaust stubs have been removed, possibly to accommodate the aftermarket 4 into 1 exhaust, but now I've noticed that the engine number starts CB750E 251****
I seem to remember reading that a 250+ prefix means an F1 engine.
Can someone who knows confirm this please  ?
I've looked in John Wyatt's book but it seems a little ambiguous about engine numbers [ Guests cannot view attachments ]

Nurse Julie:
A 1976 K6 engine starts with 254****.
It looks like a USA import, so it's probably a K5 engine . Has it got a VIN tag on the top down tube? If its a UK model, forget the above as the numbers and model range are different for UK models. In UK we had K2 from 72- early 1976, no K3, K4 or K5.
Edit... That tank is painted as K6 but the tap is  on the wrong side for a K6.

Grewth:
Thanks for the reply,  but that has only added to my confusion.
The bike is a (so far unregistered in the UK) US import.
According to John Wyatt the LH fuel tap came in with the K5 in the US.
So I could well have a K3 or K4 maybe ?
That's if the tank is the original.
Other tell tale feature is the chain oiler on the output shaft.
Not a K6 feature IIRC.
The headlamp mounts are the K6 type, but we're also fitted on some of the earlier American spec bikes too.
Apart from all the above.
If 254 is a K6 engine number prefix,  then my CB750F1 is fitted with a K6 engine.
Bugger !
Well at least it runs without rattling.
I wonder if the DVLA would give me the original engine number for the F1 ?

Nurse Julie:
Don't forget the F1 was 1976 and so was the K6. Honda didn't define a model by engines, they just kept fitting the same engine until they ran out of those engines.
The tank could have been changed and John Wyatts book  is known to contain errors.
Being a USA model, that's 50 years old, it could have had both the engine and the frame changed over the years, plus the clocks , swing arm etc. It's probably a mystery you'll never be able to solve. What are your plans with it?

Grewth:
Just planning to get it running, register it and then ride it.
Assuming that the engine still has some life left in it.
I'm not overly concerned about it being a Heinz 57 Varieties.
At least it's still a 750 Four in basically it's original form.

Navigation

[0] Message Index

[#] Next page