CT70 K0 charging

S

Salukispeed

New Member
New here but not new to ancient honda"s Have a sapphire blue KO CT 70 in fair shape for 45+ years now Runs fine everything works. Someone was in the ign switch and harness before me. The battery charges very well with the key in position one ( lights off), But Position 2 and Lights on is total loss and very slowly drops down below 6V from brake lights and tail. In position one it charges very well and will actually over charge to nearly 8V at 5-6,000 RPM. as a guess. headlight is about normal brightness when riding but possibly a "little" dim. Could the two coils wiring be reversed ( yellow--Green output to harness?
Another thought. I noticed the selenium rectifier is subbed with likely a small bridge rectifier.

I have been around honda's for 50 yers and was a honda mechanic in the 70's---early 80's. I have the factory honda manual. and Just decided to make the bike proper since my Grand Kids are coming of age. I ride the bike a few miles every summer to keep it happy. Does anyone make a repop owners manual . Is there a thread that dives deep into the wiring on these and would anyone care to share an idea or two?
Thanks
Bob
 
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Double check the headlight bulb is a 15w/15w. Did you switch to a SLA 6v 5ah battery yet? They last for 5 years. I bought the upgrade rectifier on ebay from the seller Brain Tarp. Throw in a ''red'' 6volt ''1154'' led taillight bulb as well to free up juice.
 
There are good reproduction wire harnesses available too...if you'd like to get back to stock...fresh start, etc.
 
Poor ol thing is in reasonably nice condition and complete but when I got it it had no air cleaner and had cam chain and intake valve issues. and smokes pretty bad at times, I cobbled it together back then with spare parts and with 3/16+ ring end gap its low on power, and now have a complete stock top end kit coming Wednesday (EBAY)?????. Sadly like most things it is Chinese nock off kit but will see how that turns out. Might pick and choose what parts I use. and will dig lots farther into the charging issue and study the wiring diagrahm a bit more. My 66 honda CB77 has a second stator coil brought in when the lights are turned on and I thought maybe the ct does the same but looks not to be.
Thanks for the thoughts and help
 
Cancel it! The ebay kit is going to be wrong. Seller's lie! Piston and head is for an 82 and up only. They say it fits ALL years. Not the case. The only good part will be the cylinder. Use known vendors that are honest. Dratv has what you need...
 
Okee Dokee. The ebay kit came very very quickly and I am willing to take the beating of the not fitting parts, as "OLD CT" mentioned. Lessons learned?? How do I reach out to Dratv. for proper fitting parts and or other good venders here. That I might get my 70 K0 back to snuff.
Thanks for the help
Bob
 
Thank You.
Obviously I got drawn into the Cheap Chinese Ebay thing with the kit that is only slightly useful. so having a good reputable source is great. Are there others here I should put in my Box of sources?
Thanks again
 
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