Topic: which wire harness should be on this bike

[joseimport]

i just got a cb750k in colombia south america.

the engine is a k5 and the frame is a k2.
this is how this bikes came over here and in many other places around the world.
unfortunately, the only manuals i can find are for the US k0-k6

my question is.... which wiring harness should i be using?

what determines the wiring harness? the engine number or the frame number?

i would think it´s the frame number so i guess i should be getting a k2 wiring harness, right?
also does it matter that much what year i get?  are there many differences?

what do you guys think.

[bryanj]

As you are not in US, Go to the UK site (sohc.co.uk) and look in alladins cave to download manuals and parts books of course i could not condone any body where Honda has got antzi about copyright like the US doing that ( fingers crossed and winking)
As to which loom, the later models have the starter safety circuit and liggts always on so your choice

[PeWe]

It is like an European K2, right?
K1 blinkers, K1 rear fender and light. K1 grab bar at left.

Rest of it like K2. The engine number will match K5 I guess.
Kmh speedo. Late front fork as Late K2 - K6 got wirh matching fender bracket and brake bracket.
I ordered a NOS kmh speedo  from Venezuela to my European K2 2018.
My K2 imported new 1975 from  Japan.

[bryanj]

Like in UK  everthing after K1 was K2 up until the K6 came along, frame numbers were all K2 progressively but i believe the engine numbers kept time with US models

[PeWe]

The ignition switch and battery holder with all electrical stuff is different between K2 and later.
If you have the typical 1 fuse  and round ignition switch connector, use K2. This is how my K2-1975 is done.

I could have used the later if replacing battery holder with later but I preferred to make it stock as it once was delivered even if the entire bike was built on parts.
The only parts that match the registration are frame, battery holder and tank which I painted. All other parts bought here and there.  K2 type gauges and upper tree costed a lot extra.

Engine was empty cases I filled with parts. It got a K2-K5 clutch even if later K7/F2 is much better.
Europe never got K3-K5.
K2 1972 to 1975
K6 1976
K7 1977
F1 and F2 also.

[joseimport]

The ignition switch and battery holder with all electrical stuff is different between K2 and later.
If you have the typical 1 fuse  and round ignition switch connector, use K2. This is how my K2-1975 is done.

I could have used the later if replacing battery holder with later but I preferred to make it stock as it once was delivered even if the entire bike was built on parts.
The only parts that match the registration are frame, battery holder and tank which I painted. All other parts bought here and there.  K2 type gauges and upper tree costed a lot extra.

Engine was empty cases I filled with parts. It got a K2-K5 clutch even if later K7/F2 is much better.
Europe never got K3-K5.
K2 1972 to 1975
K6 1976
K7 1977
F1 and F2 also.

i will work with a k2 harness, from the battery cage i deduced this is a k2 frame as the one i have is a complete mess...

(please check the pictures) this is the ignition it has, it's an electronic ignition, but who knows where this thing came from... or what brand it is, it has some sort of connection that i have no idea why it has it.

the electric part is the most daunting one for me, but I'm learning

i want to replace the entire electrical system....

I'm planning to get the k2 wire harness, i already got a NOS one at a great price,
a dyna S electronic ignition, without the coils, i will use the ones the bike has as they are the original ones.
i don't know if i should replace the regulator rectifier with this one  https://4into1.com/regulator-rectifier-honda-cb350f-cb400f-cb500-cb550-cb750/
or just find a good used replacements.

i need to get the original ignition switch for this bike but they are quite expensive as a kit with the steering lock and seat lock (226us from davidsilver)

i would use the k3 ignition kit https://4into1.com/genuine-honda-main-switch-kit-35010-374-671-cb350f-cb360-cb500k-cb550-cb750k/ but this has the square connection, not used in the k2 harness, i dont want to chop of any of them, if i can find a good replica i would work with that one.

[joseimport]

As you are not in US, Go to the UK site (sohc.co.uk) and look in alladins cave to download manuals and parts books of course i could not condone any body where Honda has got antzi about copyright like the US doing that ( fingers crossed and winking)
As to which loom, the later models have the starter safety circuit and liggts always on so your choice

i did this, but the manuals do not differ from the ones on this site. 

[754]

72 uses avround plug on ignition switch , square was used in 74 , maybe 73 ?    3 fuses after 73.

[joseimport]

72 uses avround plug on ignition switch , square was used in 74 , maybe 73 ?    3 fuses after 73.

yes that i can see....  so it is not possible to use the k3 ignition switch with the k2 harness.....  unless i switch the connector of the switch or the harness

one question...  i already ordered the k2 harness...

would the k1 ignition switch work  https://www.partzilla.com/product/honda/35010-315-017   

it has the "same"  round plug... but looking at my parts manual it was only for k0 to k1.. 

[754]

The round one should fit, they are usually brown coloured.