Topic: K1/K4 engine

[tato81]

Hello. I have a Honda CB 750 Four K4 from 1974. I'm from Poland - sorry for my english. I have a few questions and I know that here I find specialists. I want to buy a engine from the K1. Will be using it a part of my K4? Is it two completely different egine? Second question about the color of Flake Sunrise Orange. Can somehow reproduce that color. Are there any codes or tips? Do I need to buy paint it on ebay?

[Johnie]

Hello. I have a Honda CB 750 Four K4 from 1974. I'm from Poland - sorry for my english. I have a few questions and I know that here I find specialists. I want to buy a engine from the K1. Will be using it a part of my K4? Is it two completely different egine? Second question about the color of Flake Sunrise Orange. Can somehow reproduce that color. Are there any codes or tips? Do I need to buy paint it on ebay?

You can get the paint from www.vintagehondapaint.com  Once you send Don a note on what you need, keep in mind it takes him a little while to respond with cost. He is a little slow in responding, but he will get to you. His paints are true to the color and he did his homework to match the color of that era. Many guys here use his paints and like the quality and match.

[Hinomaru]

Welcome to the forums ...

Since you're located in Poland, here's a couple of European paint sources:

http://www.rsbikepaint.com/

http://www.motorradlack.de/index.html  (click on the English flag icon)

If you have access to House of Kolor products in Poland, see this forum FAQ:

http://forums.sohc4.net/index.php?topic=62274.0

You could also ask about other paint sources over on the SOHC UK site:

http://www.sohc.co.uk/

(Edit to fix broken link)

[Old Scrambler]

Welcome to the group..........Be sure to use consistent model IDs between Europe and America. The K1 motor will swap with the K4 but may require carb tuning depending on the type of exhaust pipes. 

[tato81]

Welcome to the forums ...

Since you're located in Poland, here's a couple of European paint sources:

http://www.rsbikepaint.com/

http://www.motorradlack.de/index.html  (click on the English flag icon)

If you have access to House of Kolor products in Poland, see this forum FAQ:

http://forums.sohc4.net/index.php?topic=62274.0

You could also ask about other paint sources over on the SOHC UK site:

http://www.sohc.co.uk/

(Edit to fix broken link)

Thanks for the good advice! These websites are helpful to me!

[zzpete]

  Welcome to the forum. How about a picture of your bike!   

[CB750faces.com (Lecram)]

Engines can be exchanged without problems. The K1 has the same carbs.

Where did your bike originally come from? It can only be a K4 if it is imported from the US. The K4 hasn't been sold in Europe.

[tato81]

  Yes, my Honda came to the US ( Southington CT). I will try to put pictures in a few days. My Honda is not entirely original. It is now on wheels "Lester", but I bay the original. And i'm looking for original exhaust system. Generally have some work waiting for me

[CB750faces.com (Lecram)]

David Silver Spares in the UK sells a lot of parts for our oldies. And is not that expensive

[tato81]

Here are two pictures of my Honda:

[Prospect]

Hello. I have a Honda CB 750 Four K4 from 1974. I'm from Poland - sorry for my english. I have a few questions and I know that here I find specialists. I want to buy a engine from the K1. Will be using it a part of my K4? Is it two completely different egine? Second question about the color of Flake Sunrise Orange. Can somehow reproduce that color. Are there any codes or tips? Do I need to buy paint it on ebay?

You can get the paint from www.vintagehondapaint.com  Once you send Don a note on what you need, keep in mind it takes him a little while to respond with cost. He is a little slow in responding, but he will get to you. His paints are true to the color and he did his homework to match the color of that era. Many guys here use his paints and like the quality and match.

I believe because paint is classified as a "dangerous good" he doesn't ship outside of the US.  Too bad, I wanted to buy paint from him for my K1.  

[Old Scrambler]

Unless you really have mixed parts.............that looks like a US-spec K3........same paint as mine!

[tato81]

Unless you really have mixed parts.............that looks like a US-spec K3........same paint as mine!

I think that your K3 is in color "CANDY BUCCHUS OLIVE". Unfortunately mine K4 is black.

[tato81]

How to identify from which the model is the engine? It is the engine for the K1? Seller just told me that the K1

[CB750faces.com (Lecram)]

How to identify from which the model is the engine? It is the engine for the K1? Seller just told me that the K1

Tell us the engien number and we can tell you if this is a K1 engine (The head isn't K1)

[tato81]

How to identify from which the model is the engine? It is the engine for the K1? Seller just told me that the K1

Tell us the engien number and we can tell you if this is a K1 engine (The head isn't K1)

engine number is: CB 750E-2558349

[CB750faces.com (Lecram)]

How to identify from which the model is the engine? It is the engine for the K1? Seller just told me that the K1

Tell us the engien number and we can tell you if this is a K1 engine (The head isn't K1)

engine number is: CB 750E-2558349

This is not a K1 engine. I think a K4 or K5 (74 or 75)

[zzpete]

Looks like its a K6 or possibly a F1. Check out this link for a timeline on engine numbers.
http://www.hondachopper.com/engine/engine_timeline/timeline.html

[tato81]

Looks like its a K6 or possibly a F1. Check out this link for a timeline on engine numbers.
ttp://www.hondachopper.com/engine/engine_timeline/timeline.html

Yes, i think it's K6 engine. What is the diferent between K4/K6 engine?

[zzpete]

This link shows the engine modifications through the years.
http://www.hondachopper.com/engine/engine_mods/modifications.html

[HondaMan]

Looks like its a K6 or possibly a F1. Check out this link for a timeline on engine numbers.
ttp://www.hondachopper.com/engine/engine_timeline/timeline.html

Yes, i think it's K6 engine. What is the diferent between K4/K6 engine?

There are only minor cosmetic differences between K4-K6. There are some ribs in the fins that changed shape a little bit, nothing more though the rest of the engine. They are completely compatible and interchangable, and use the same internal parts. The carburetors changed numbers between 657A and 657B on those engines, but internally were also identical, with the same jetting. The air screws on those carburetors should be set at 1 turn from the inside stop (gently). Those are VERY reliable engines.

Those Lester mags are great! 
They are very hard to find here in the U.S. 

[tato81]

Looks like its a K6 or possibly a F1. Check out this link for a timeline on engine numbers.
ttp://www.hondachopper.com/engine/engine_timeline/timeline.html

Yes, i think it's K6 engine. What is the diferent between K4/K6 engine?

There are only minor cosmetic differences between K4-K6. There are some ribs in the fins that changed shape a little bit, nothing more though the rest of the engine. They are completely compatible and interchangable, and use the same internal parts. The carburetors changed numbers between 657A and 657B on those engines, but internally were also identical, with the same jetting. The air screws on those carburetors should be set at 1 turn from the inside stop (gently). Those are VERY reliable engines.

Those Lester mags are great!  
They are very hard to find here in the U.S.  

Thanks for showing the differences.
Yes, lester mags are great, but I prefer the original wheel.
If the wheels are on the bike, I plan to paint them the color of gold, like in the photo:

[david 750f]

I think that may be a 1976 F1 motor.. The serial number is within a 1000 units of my 1976 CB750F.

[tato81]

I think that may be a 1976 F1 motor.. The serial number is within a 1000 units of my 1976 CB750F.

Yes, but F1 engine has serial number CB750FE, and my has a serial number CB750E
How I can see is this F1 engine or K6?