I personally have the Kirker color chip chart and have compared it to ruby red, topaz orange and candy yellow. The K1 3-speed & HK1 4-speed candy yellow is in fact a very close match to Kirker Electric Lime candy (UC50), so yes, that color is sorta greenish. HOWEVER, you cannot shoot Kirker candy over Kirker Quicksilver base (UCB01) and have it match the original Honda 2-stage paint job. This is because the Quicksilver is super-disco aluminum flake, and will not match any CT paint. You must use a smaller metallic particle to match. I would recommend shooting the Kirker candy of over NH35M (Cloud Silver) as two coats cloud silver followed by 3-5 coats candy. I would skip clearcoating as the Kirker candy is just a candy concentrate added to clearcoat, so it will setup and be fairly UV resistant.
Also be aware that all Kirker paint is single stage, meaning it is clear with concentrates, metallics, etc mixed in. If you paint as Kirker recommends (they are trying to sell you paint), 2 coats Quicksilver, 4-5 coats candy and 2-coats clear, then your paint will be (2+4+2)*.0013"= ten thousandths thick!!! that's stupid thick!
You can also buy your own candy concentrates and add a few drops to clear coat of your local supplier to save some bucks. This isn't rocket science, but some experimentation with test cards is advised to make sure you get the proper number of coats to achieve the orignal match.
Here are some close matches for the OE CT70 paint:
3-4 coats Kirker Chianti Candy (UC10) over NH35 single stage urethane = ruby red (this is a dark red, not a bright red)
4-5 coats Kirker Atomic Orange (UC30) over NH35 single stage urethane = topaz orange (this is a dark orange, not a bright orange)
A huge benefit of using NH35M (PPG code 33778), is that you can shoot your wheels at the same time you are shooting the frame, forks, headlight bucket, etc. Since it's single stage, the wheels are done. After the wheels are tack free (1-2 hours), remove them from the room and spray a few coats of translucent candy on the frame and forks, etc whithin 24 hours and you are finished! No need to have several different expensive paints, nor several different paint types (i.e. tri-coat). Honda only did a two-stage, why should you do three? FYI, if your taillight bracket is rusty, you can abrasive blast it, epoxy primer and paint it cloud silver. Yeah, it's not original, but it looks pretty good and for a low-buck restore, looks way better than rust....
Anyway, that's my experience. Try it, you'll save a ton of money and the color is pretty close...
EDIT: More advice: Shoot your footpegs, tank bracket and K1+ headlight bucket with acrylic enamel satin (trim) black. This stuff is cheap and can use the same reducer used in the urethane single stage and clears. DO NOT SCREW UP LIKE I DID AND ADD HARDENER!!! It had been awhile since I last shot the trim black (shot the trim on a turbo Z) and the label had drips on it. I just mixed it up like normal acrylic enamel and added 4 :1 :1, paint:reducer:hardener... Unfortunately, hardener is NOT added to satin paints as it WILL make it gloss out just like regular gloss black... Now, my HKO and K1 have gloss black parts, DOH!!!!
EDIT 2: Turns out, I do have experience with candy yellow... That is the color that was on my 8/71 K1 3-speed. I always just assumed it was candy gold. So, the edit in all references above consists of replacing "Candy Gold" with "Candy Yellow".
http://www.ct70honda.com/CT70ModelIdentificationGuide.html Yes, I did match a non-faded part of the bike to my Kirker chip chart, and it was definitely electric lime candy (UC50). I did not go back with this color (ruby red instead), but would bet a dollar to a donut, this is a very, very close match (especially over NH35M)...
