Author Topic: restoring my CB750 K0 12/69 (Read 6972 times)

esantella · « **on:** July 24, 2016, 02:49:07 PM »

hello to all of you, im looking for some guidance to restore my K0. I own a custom restoration shop in Guatemala named Chiltepe Motors, even though I could work on it with my mechanics; we are full of customer restorations and they are priority so I decided to take on this restoration on my own. need some help.

1. I have just bought a new 1-4 throttle cable and have some questions regarding the assembly: is there a specific way to connect the cables to each carb? don't see any labeling.

2. I will be servicing my carbs with a rebuild kit and polishing them as well... is there someone who can guide me through the steps to reset the mixture screws?

3. Paint providers for my Candy Blue Green have been doubtful, any recommendations on who is the right one?

4. My honda Tank emblems are worn out.. Anyone have a picture or reference of how the original look was?.

sharing some pics of my bike. all the best from Guatemala, Central America.

regards

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ekpent · « **Reply #1 on:** July 24, 2016, 04:14:51 PM »

Nice looking bike,is the paint original. If it is I would leave it alone and polish it up,worth more in my opinion if its a nice original survivor.
Have you taken the air box off yet ? If not be VERY careful as it is made from the same material as the side covers and will be very brittle from the gas fumes etc. Also be forewarned that the plate that holds the carbs together can be weak and brittle also in the center and care must be taken when removing the rack. Use a heat gun on the rubber manifolds and some spray lube won't hurt. On those carbs the tops screw off and the slide will pull out and that is where the cables connect. Try to reuse all the stock brass in the carbs instead of aftermarket if original, its better. If you have brass floats look them over well for damage,not uncommon. Emblems can easily be restored.
Tell us more about the bike like mileage, serial numbers, is it a runner, is it a USA model etc etc.
And most important welcome to the forum !!

beemerbum · « **Reply #2 on:** July 24, 2016, 04:18:14 PM »

Welcome. Nice bike. That bike needs restoration?? YGBSM!

Tews19 · « **Reply #3 on:** July 24, 2016, 06:30:49 PM »

That is one great looking bike!

Don R · « **Reply #4 on:** July 24, 2016, 07:30:37 PM »

In my humble opinion, the less you do to it, the better. Especially if that's the original paint. nice cut front fender, it appears very original.

esantella · « **Reply #5 on:** July 24, 2016, 09:05:04 PM »

Thanks to all of you for your comments and thank you for the warm welcome. It took me quite a while to find this Jewel, looked everywhere for it and my luck payed me a visit just a few months ago. even though I am young I have a strong appreciation for vintage bikes, which led me to begin my personal collection and then to open my restoration shop Chiltepe Motors. I am also an advocate of leaving things as they are, specially when they are in such good shape. Even though the bike looks good, it does need a little TLC and this is why I joined this wonderful forum.

So here's a little history of how I got this baby... about two years ago I started looking for a wonderful CB750, my dream was to find a Sandcast Model but that was going to take some enormous effort..Finally mid last year I stumbled across this wonderful K0 from a great man in Maryland, a retired Sherif...this man had a wonderful CB collection everything from 72 all the way up to 79. I would call this man at least two or three times a week to see how I could negotiate and get his collection shipped down to my country Guatemala. After about three weeks of back-and-forth calls and some pretty cool historical facts about his life he tells me "Eduardo you seem like a nice guy...I can't tell you how it hurts for me to sell my collection but I'm really sick and tired of moving the bikes to get my Can-am's and my Harleys out of the garage... I am getting old and I want to enjoy the rest of my life and pass on my collection to someone who values it" he then goes on to tell me he will call me tomorrow because he has something important to tell me, but he was going to talk it over with his wife... He left me intrigued... so he calls the next day and says "Eduardo, so I talked it over with my wife and I would like to offer you my gem: a 1969 K0 Diecast" I flipped out and I immediately said yes and we agreed on a price, a great deal..

It took a while to get it shipped and through customs but it finally arrived 3 months ago, new battery, new wheels and a full service and she runs great... since I am new to the specs and details of this specific model, I have been reading and reading more about this great bike. Everything is pretty original and in very good shape, the paint job on the tank and the side covers appear to be repainted. The reason I believe this is so is because the stripes on the tank are painted, correct me if I'm wrong as I have not been able to find if these stripes were originally stickers or painted?. The side covers apear to be original but have 2 gold/black line stickers under the clear coat, still haven't seen references for these being originally part of the model. The airbox appears to be the original paint along with the front parts of the bike. Unfortunately I don't have the serials on hand right now but I will be more than happy to send over the specs tomorrow.

So I gave you a little story of the bike..

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esantella · « **Reply #6 on:** July 24, 2016, 09:23:48 PM »

Forgot I had some pics he sent me before I purchased it. 1 single owner, The Mileage is 24,500. Here are the pics..

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dhall57 · « **Reply #7 on:** July 25, 2016, 12:22:34 AM »

Welcome from North Carolina. Looks like a nice one esantella. You lucky guy

to have a nearly original early die cast KO. I have a 4/70 KO and really like it. If it's the original tank it should be what is called wrinkled. Open up the cap and the first thing you see should be the grooved metal not smooth. Also are all the pipes HM341's they look to be in good shape. But they've been changed out sometime because the KO's came with HM300 pipes witch are less restrictive and more of a of performance pipe. I see the double cut front fender also like Don said. They came on sandcast and earlier KO's like yours. The bike still has the KO air box to, that's rare. Of course the rear shocks have been replaced and looks like the ducktail seat has maybe been recovered. I agree with the other guys clean it up and fix what needs to be fixed and ride it. Good luck and again nice bike

Sgt.Pinback · « **Reply #8 on:** July 25, 2016, 04:14:53 AM »

Quote from: esantella on July 24, 2016, 02:49:07 PM

hello to all of you, im looking for some guidance to restore my K0. I own a custom restoration shop in Guatemala named Chiltepe Motors, even though I could work on it with my mechanics; we are full of customer restorations and they are priority so I decided to take on this restoration on my own. need some help.

1. I have just bought a new 1-4 throttle cable and have some questions regarding the assembly: is there a specific way to connect the cables to each carb? don't see any labeling.

2. I will be servicing my carbs with a rebuild kit and polishing them as well... is there someone who can guide me through the steps to reset the mixture screws?

3. Paint providers for my Candy Blue Green have been doubtful, any recommendations on who is the right one?

4. My honda Tank emblems are worn out.. Anyone have a picture or reference of how the original look was?.

sharing some pics of my bike. all the best from Guatemala, Central America.

regards

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Nice find, congrats!

There are two longer and two shorter cables. Long to No. 1 and 4, short to No 2 and 3

Dont polish carbs. That looks bling-bling. They have nice genuine finish as far as I can see.

New paint on that bike would be a shame. If you insist, I think I have a spare set of color that I could sell /send to you.
Stripes on K0 fuel tank had been painted, no stickers. At least on early K0´s like yours.
So for me thats evidence that the paint is original.

No such stripes on the side panels. Carefully take them of or leave them as part of the bikes history.
Take off the fuel tank and lets have a look at the underside and we will see more if its re-painted or not.

Nice patina on emblems. Nw look like this in pic below

What I would do and look for:

- correct "HM300" pipes. Those on yours came with K2-K6
- correct "dull" heat shileds for the upper pipes
- correct KO mirrors (see pic)
- not sure if the seat is original, may be a repro
- correct black K0 kill knob (see pic)
- correct rear K0 dampers
-
-

edit:

see you have KO rear dampers in the pic with the fairing. Restore those and save a lot of money!

Johnie · « **Reply #9 on:** July 25, 2016, 06:18:48 AM »

What can I add...how about another welcome to the forum! Excellent looking bike and congrats on your find. Keep us informed on your progress.

esantella · « **Reply #10 on:** July 25, 2016, 07:46:05 AM »

Thanks to Dhall, Sgt P, and Johnie! for your valuable information, she truly is a good find.

Im really glad to hear that originally the tank had painted stripes! I had not been able to find reference to this detail. This and the stripes on the side panels were the only reason why I was considering re painting it, so that's out of my "to do list". Right after I read the responses I went towards my garage to check the bike and the tank is the wrinkle version....relief....

The pics I sent are from when she arrived, since then I have replaced to rear shocks back to the originals. The seat was reproduced in my shop because the original was totally damaged.

So here are the following steps:
- NOS mirrors
- NOS handlebar controls
- NOS cables
- NOS brake/clutch levers
- NOS heat shields
- try to find the HM300 pipes (for now the ones on mine are fine)
- Polish the paint and leave as is.
- clean/check/tune the carbs
- I do have to check the clutch and basket.. (I hear the disks rumble a bit when in Neutral, don't know if this is normal.)

that's all folks... I will be sending more pics once I get these things done. thanks again..

would like to share some pics of a restoration/modification we are finishing at the shop on a 1980 CB750 custom "THE CB KING" and a also a 1974 CB750.

enjoy...

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Johnie · « **Reply #11 on:** July 25, 2016, 08:06:16 AM »

Sounds like you have the familiar "clutch rattle" which is normal. Most have it. Pull in the clutch and it will be better. Something we just live with...no big deal.

ekpent · « **Reply #12 on:** July 25, 2016, 08:07:04 AM »

So is the vintage bike scene pretty big down in your part of the world ?,looks to be by some of your other creations. What are vintage bike prices like in your region,expensive or fairly priced ?

esantella · « **Reply #13 on:** July 25, 2016, 03:28:43 PM »

Well to be honest we are the one of the few restoration shops in the region, the scene was started by my business partner and I about 3 years ago holding monthly meet ups and rides. We have been blown away of the response and interest from people and hidden collectors all over the region. Prices are still low on barn/garage and classified finds but this year massive surfing on the internet has informed many of the locals that vintage bikes are worth money. The interesting thing about Guatemala, El Salvador, Honduras and Costa Rica is that many big brands opened their dealerships in the 1940's with direct imports and very few US model versions, so you do find some interesting motorcycles at low prices. check out my shop www.facebook.com/chiltepemotors

Sgt.Pinback · « **Reply #14 on:** July 25, 2016, 09:43:23 PM »

Sounds like a lot of fun.
Great pics!

esantella · « **Reply #15 on:** July 25, 2016, 10:00:48 PM »

Thanks Sgt. P!

So I wanted to give you guys an update. Finally got the sticker stripes off the side covers

and I have also corrected the throttle cables. Now something interesting occurred while starting up the bike.. Had massive acceleration, then the RPM went all the way down close to the motor shutting down. I had followed the manual instructions and set the screws correctly. Heard some loud pops coming from the carbs not the exhaust, I forgot to state that when I reassembled my airbox, the hoses did not go in all the way. Maybe this is why? Air leaking between the hoses and carbs?.

Love to hear your thoughts and suggestions.
Regards

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Sgt.Pinback · « **Reply #16 on:** July 26, 2016, 03:41:14 AM »

Air leaking between carb and airbox should not give that trouble.

When you start up revs go high without pulling the throttle cable and then go down by itself?
Did it do the same before you changed the throttle cables?

Johnie · « **Reply #17 on:** July 26, 2016, 05:13:15 AM »

Not sure how much carb cleaning and rebuilding you did, but did you sync not only the high at 3,000 RPM's by each cable adjustment located on top of the carbs? Then you have to sync the low idle by the big round screws on the side of each carb.

Sgt.Pinback · « **Reply #18 on:** July 26, 2016, 05:49:24 AM »

I assume he made a mistake with the slides.

Either changed them left/right and they dont go along with the adj. srews or they are turned inside the carb by 180° and do not go down all the way.

Phoenix · « **Reply #19 on:** July 26, 2016, 07:03:46 AM »

Welcome again. The following link may help you with your questions.
http://honda750expert.com/
Good luck.

esantella · « **Reply #20 on:** July 26, 2016, 07:04:20 AM »

Cleaned the carbs with carb cleaner and i did place the slides correctly, they went in all the way. I keep hearing that you should see a "T" on the low idle screws? Can't identify them. Would anyone be so kind to guide me through how to adjust all parameters, measurements, from where do you measure from and reset settings to sync them would really be a big help.

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Johnie · « **Reply #21 on:** July 26, 2016, 08:43:24 AM »

The carb sync is really the very last thing you should do...after adjusting the valves, new points, condensors, timing and basically the 3,000 mile tune up. But to answer your question...first do you have a vacuum sync gauge. The one pictured below is a Morgan Carbtune.

esantella · « **Reply #22 on:** July 26, 2016, 03:53:45 PM »

Thanks for the info.

regards

esantella · « **Reply #23 on:** July 31, 2016, 08:45:03 AM »

so almost done with the final touches on the bike, but for some strange reason my throttle grip is stiff. it doesn't rotate easily, the cables are new and are not being pulled or stuck anywhere...any thoughts of what could be causing this?. regards

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Sgt.Pinback · « **Reply #24 on:** July 31, 2016, 11:12:36 AM »

Screws on handle grip too tight?

No issues with the slides?

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Author Topic: restoring my CB750 K0 12/69 (Read 6972 times)