Author Topic: 1971 CB750 Project by Cedric (Read 3046 times)

cfairweather · « **on:** August 18, 2022, 05:20:23 AM »

I just started a new project and it is a 1971 K1 CB750. It has about 20K on the odometer and has not been on the road since about 1983. This will probably be my last CB750 project because it is getting so expensive to restore one. I have two others in the garage that I did over the past few years. I took it all apart and I will post some pictures of the project occasionally. I just finished painting the bike and I did it along with two GL1000s that I am also working on. See these pictures below but the parts actually look much better than these pictures.

newday777 · « **Reply #1 on:** August 18, 2022, 05:35:49 AM »

Nice. Did you use the same red on the gl parts?

cfairweather · « **Reply #2 on:** August 18, 2022, 05:46:58 AM »

Yes, same paint, but I used a different base on the CB750 parts. These have a base color called stellar silver which is highly reflective with lots of metal flakes in it. I used a silver primer on the GL1000 parts for the base color.

MauiK3 · « **Reply #3 on:** August 18, 2022, 07:59:54 AM »

We'd all love to see more photos and heap praise on you for doing the work!!

Shtonecb500 · « **Reply #4 on:** August 18, 2022, 09:29:06 AM »

thats the sexiest trailer bed ive ever seen.

Stev-o · « **Reply #5 on:** August 18, 2022, 02:09:17 PM »

Subscribed...

bek1966 · « **Reply #6 on:** August 18, 2022, 05:45:15 PM »

Fantastic paintwork! Looking forward to updates and you progress. Thanks for sharing.

Brad

SOHC4 Cafe Racer Fan · « **Reply #7 on:** August 18, 2022, 08:12:04 PM »

Great work on the paint!

WideAWAKE · « **Reply #8 on:** August 19, 2022, 10:49:43 AM »

Very nice paint work!!

Gurp · « **Reply #9 on:** August 24, 2022, 04:39:29 PM »

*following

cfairweather · « **Reply #10 on:** August 27, 2022, 05:03:10 PM »

Thanks for your comments and I hope you enjoy this short update. I started working on the the engine. It is in pretty good shape, but I did find one bent shifting fork. I had a spare that came from a K3 engine, so no big deal. I also installed new cryo treated primary chains from Cycle-X. You probably noticed that the pictures show I loaded the lower half instead of the upper half. I know, the manual says load the upper half first, but I think this way is easier. I like being able to fully test the transmission before closing the case. You might also notice I found a good use for packing peanuts. This is a simple way to hold the rods in the middle of the hole.
I cleaned the case with a high pressure sprayer and then used an ultrasonic cleaner for about 30 minutes per side. Then I painted them. As you can see I got the shifter parts installed too. Here are some pictures of the progress.

newday777 · « **Reply #11 on:** August 27, 2022, 05:22:34 PM »

Nice.
That ultrasonic cleaner must be big to fit the case halves in it. What solution do you use for cleaner?

cfairweather · « **Reply #12 on:** August 27, 2022, 05:35:22 PM »

It holds about 6 gallons, so I have to turn the case four times to get it all clean. I mix about two cups of KrudKuttter Concentrated cleaner and degreaser in with clean water.

WideAWAKE · « **Reply #13 on:** August 28, 2022, 07:40:07 AM »

It seems to be some what of a split consensus here and it also seems to be done both ways from the factory, but I was always thought to stagger my chains.

Has there been any definitive conclusions on this???

cfairweather · « **Reply #14 on:** August 28, 2022, 07:54:38 AM »

Sorry, I don't understand what "stagger my chains" means.

WideAWAKE · « **Reply #15 on:** August 28, 2022, 08:20:23 AM »

Was in reference to the primary chains.

You can either have them how you got em, lined up, or if you shift one chain one link, they would then be staggered.

I’m not saying, one is right the other is wrong.

Your photo prompted the thought in my head if there had been any conclusive determination one was vs the other.

Mine was staggered from the factory, it went back staggered, but I was also always thought it’s best to stagger them.

cfairweather · « **Reply #16 on:** August 28, 2022, 09:30:25 AM »

Oh, I see what you are referring to, but take another look at mine and compare it to yours. Mine is staggered too, but I did not plan this. Find a link where the bars on on the inside. Now compare it to the same link on the other chain and you will see the bars are on the outside. Seems like staggering would be better, but I have no idea. In any case, I don't plan on opening the case again unless this is a serious mistake

.

I know Hondaman says they should stay on the same side as they came out, if you reuse them.

WideAWAKE · « **Reply #17 on:** August 28, 2022, 09:40:41 AM »

Ahhh you are correct!

I didn’t have my glasses on haha.

And even if they weren’t, I don’t think it would warrant opening the cases to adjust.

It seems they came from the factory both ways.

cfairweather · « **Reply #18 on:** September 08, 2022, 02:53:51 PM »

The top end going back together. I used standard gaskets from 4into1 and I always use copper coat on the head gasket. It has always worked great for me, so I continue this practice. The cam chain is a new heavy duty Tsubaki along with new tensioners.
DSCN4270.jpg
DSCN4269.jpg

MauiK3 · « **Reply #19 on:** September 08, 2022, 03:03:08 PM »

Looking great!

HondaMan · « **Reply #20 on:** September 08, 2022, 08:20:16 PM »

Wait!
Did you already bolt the head down?
You need thicker O-rings in the oil ports of the head gasket, or it WILL leak oil, very soon.
PM me your address, I'll send you a pair...

cfairweather · « **Reply #21 on:** September 09, 2022, 03:43:28 AM »

I already bolted it down but the picture is deceiving. The head gasket is bowed a bit and makes it look like they are too short. I think they will be ok, but thanks for the offer. I had another gasket set like the one I used so I decided to measure the orings that I used. They were the correct size.

cfairweather · « **Reply #22 on:** September 10, 2022, 12:23:55 PM »

I wanted to do a quick update on my advance unit since this seems to be a problem for many people. After I cleaned it up and inspected the unit, I determined the springs were not usable. Many times you can just remove a loop and use them but this set was in bad shape so I went to the hardware store and bought an assortment of springs for about $5.00. In this assortment, I found a spring that was pretty close to the original. After I cut two pieces down to the right size and spent an hour getting them exactly alike, I installed them to see how they worked. Just about the same tension as an original unit, but I will have to test the advance curve to see if it is close enough. I have the AD125-01 unit. Also, have you noticed that many of the advance units have a bit of slop in the locking pin hole. To further explain... after you install the unit you can often wiggle the entire unit due to the slop in this pin/hole. I placed a piece of heat shrink tubing around the pin to remove the slop.

WideAWAKE · « **Reply #23 on:** September 10, 2022, 01:25:30 PM »

Quote from: cfairweather on September 09, 2022, 03:43:28 AM

I already bolted it down but the picture is deceiving. The head gasket is bowed a bit and makes it look like they are too short. I think they will be ok, but thanks for the offer. I had another gasket set like the one I used so I decided to measure the orings that I used. They were the correct size.

What were the measurements?

cfairweather · « **Reply #24 on:** September 10, 2022, 05:04:16 PM »

ID: 11, HT: 2.5, OD: 16
I might start the engine and run it for 30 minutes before I put it in the frame to make sure nothing leaks.

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Author Topic: 1971 CB750 Project by Cedric (Read 3046 times)