70 CT70 K0 help

Just picked up a 70 CT70 K0, typical barn find, dirty, rusty, crusty, will need alot. That being said, it did fire up with some starting fluid so I'm starting from a decent point electrically. Here's my question, the battery and box were missing, there is one 4 wire connector into the main harness. My wires are blue, gred, and two black that are bypassed back to each other. Is this the normal configuration? I know red is power hot, black is ground, what is the blue? I also know there's a rectifier that's supposed to go in there somewhere, I have an orange one from a previous build that should work. I've already ordered a new aftermarket harness and will replace it all eventually, just want to get a battery in it to get it running. Any help would be greatly appreciated, thanks!
 

andrewdell19

Active Member
The black wire needs to be looped which it is to make it run without a battery. The Blue should be the negative on the battery. Red positive of battery. I would recommend a harness like this for the battery so you can get a sealed battery and not worry about acid spills. This is for a k1 so will not work for a k0 but this guy usually sells one for a k0.

https://m.ebay.com/itm/Honda-ct70-s...459285?hash=item44132c7ed5:g:RKYAAOxyYSJR~V6I

https://www.batterystuff.com/batteries/electronic-security/6-volt/sla-640.html
 
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Thanks for the lead, I got everything wired up correctly and a new battery installed, just not getting any spark at the moment. The guy I bought it from said he had it running on "starter fluid" just a few weeks ago, but I took it to the car wash and sprayed it off on the way home, I've probably got something wet somewhere. The wiring didn't look great and I already ordered a new reproduction harness from eBay, so I'm going to get that installed and see if it helps, before I do any real troubleshooting on the no spark issue. Thanks for your response!
 

andrewdell19

Active Member
Post a picture of how you have your battery hooked up. Those two black wires needs to be looped regardless if you have a battery in it or not. A normal battery connector would have that black wire connecting to two black wires on the connector like in the link I posted before.

do you have the key switch on? Have you tried both key switch positions? How are you testing for spark? You mentioned it didnt have a battery or battery box... can you post a pic what your wiring looks like under the seat? You may have gotten a few wires wet but they should dry out...

Unfortunately its hard to trust someone just saying oh yeah I had it running a few weeks ago should be fine. That being said only a few times have I had a bike that I didnt have spark on it and both times they were dumb situations. But points and condensor are good places to start regardless on a tuneup.
 
Actually, I had bought a battery previously which came with the correct "plug and play" wiring for it, so the black ground wires are looped back to each other in that new connector, and the blue/green are color coded and going into the harness in the correct path to those same colored wires, the plug will only fit into the harness one way regardless. I've ordered new plugs and wiring harness, so once that gets here, I'll do some more troubleshooting. I've been "testing" to see if there is spark by the old fashioned method of pulling the plug and laying it across engine in a "metal on metal" location, to see if I'm getting spark. The ignition switch is in the correct connection, I've got power to the horn and I also tested power to the tail light, simply because that wire was already broken and I pulled it out of the way and it was just hanging there out of the way. I can always use my voltmeter to connect directly to the spark plug, but I've usually found that the "eyeball" method of seeing a spark works 90% of the time. It was light outside too, I may try it again in the garage in a darker setting. I know it's getting fuel, I have not done anything with points or timing yet, simply because I believe the previous owner that he had it running just a few weeks ago. He's actually a "friend of a friend" and I don't think he had any reason to lie to me, I PROBABLY should have tried to make it run BEFORE taking it to the car wash, but hindsight is 20/20. LOL.
 

andrewdell19

Active Member
Yeah sometimes the light has played tricks on me, but you are right you should still be able to see a spark in the daylight... BUT it is always worth it to try it in the garage as you may see a faint spark... sometimes a faint spark isn't enough to make it fire. If you do see a faint spark, I would say replace the spark plug first as it may be fouled (is it black? is it old?). Then if that doesn't fix the problem, make sure the points are gapped correctly. If they are and still no spark, then I would replace points, and condenser, and spark plug and try again. If THAT doesn't work then you may have a bad coil- not a huge cost item but its kinda of a paint to get to!
 
Yea, I have a new wiring harness and spark plug in the mail. Just for grins, I removed the points cover last night to make sure I didn't have any water or condensation in there, there was although it wasn't "under water", but could have been hindering the points from working correctly. It's all drying out now, I'm still trying to figure out how to get to that big plug/main connector that runs from the points into the middle of the frame? It's really the only other connection I couldn't get to from up top, but it could have easily gotten water inside of it. Any tips on getting to that connector? Other than taking the gas tank out to get a little more room up top, I don't see how to get to it from the bottom? Is it possible? I'll have to figure it out regardless if I end up replacing the entire harness!
 

andrewdell19

Active Member
You should just be able to unplug the engine from the main wiring harness pretty easily... if not may mean the harness is twisted up. Id just pull the tank replace the wiring and coil if its been under water!!
 

andrewdell19

Active Member
Oh oh right... i mean if you believe the previous owner then yeah just let it dry out for a week or two. Un plug connections etc. Then try again.
 
So it looks like the only way to get to that big connector is to remove the gas tank? I mean, I have big fat hands, and I can't even get down there with a pair of needle nose pliers to get to one end of it. Even if I was able to pull it apart, I don't see any way I would be able to reconnect it. Unless there's some trick I'm missing, I know removing the gas tank ain't that big a deal, but it's full of gas so I'll have to drain it first.
 

kirrbby

Well-Known Member
Getting it wet should be no problem, and it should be dry by now. The very first place to check should be the points. Did you check the points gap?? Did you check to see if the points are dirty/corroded?? Definitely do that. Also look around in there, under the flywheel (stator) to see if everything looks neat and tidy. No bare wires, excessive dirt, or oil...oil is bad in there.
Clean the spark plug with a wire brush.
Do you have a flywheel puller? You need one for sure if you own a lilhonda.

The plug, engine to frame wire harness, SHOULD, be JUST inside of the frame where the fuel lines come out. Remove the airbox, then try to pull on the engine wires to pull the plug out...it should be visible there, and should come out.
 
Getting it wet should be no problem, and it should be dry by now. The very first place to check should be the points. Did you check the points gap?? Did you check to see if the points are dirty/corroded?? Definitely do that. Also look around in there, under the flywheel (stator) to see if everything looks neat and tidy. No bare wires, excessive dirt, or oil...oil is bad in there.
Clean the spark plug with a wire brush.
Do you have a flywheel puller? You need one for sure if you own a lilhonda.

The plug, engine to frame wire harness, SHOULD, be JUST inside of the frame where the fuel lines come out. Remove the airbox, then try to pull on the engine wires to pull the plug out...it should be visible there, and should come out.

Yea, I pulled the cover off to look at the points, nothing horrible in there to the naked eye. I installed a new plug and tried again last night in the dark, and I'm not getting any spark at all. I don't even have an airbox on currently, but that main plug is DOWN inside the frame, and there's nowhere from the bottom to get to it, I only see access from the top side. I am getting power to the horn and to the tail light when I turn the key on, so I've probably just got your typical "no spark" issue, which really surprises me because the guy I bought it off of was a friend of a friend, and I didn't pay that much for it, I don't think he had any reason to lie to me about it. He even offered to pull it outside, shoot some ether in there and have me listen to it run, but it was raining at the time and I told him not to worry about it. Not only did the bike get rained on for about an hour, I immediately took it to the carwash to wash it off after it stopped raining, that why I was hoping it was simply some wiring that got wet, but of course, nothing is easy. That being said, I may be putting this one on the back burner for a spell anyways. I just fell into TWO H models and will be heading out after work to pick them up, so my attention will probably go to them BEFORE I even get this one running. I'll post some pics of the new H's later on this evening in a new thread. Could be the find of a lifetime if they are what the owner says they are, fingers crossed!
 
My luck turned around today, look what I just found in a condo storage unit, in Crestview Hills, KY. Don't ask what I paid, I'm ashamed to say but it was less than anyone could guess. It was on Craigslist yesterday for about 2 hours when I saw them. One has 3K miles, the other 5K miles, story I got was that they were in his family since day 1, his Dad got them new in 1971 in Florence, KY, his brother also got one. 10 and 12 years old at the time! He said they walked into the dealership, picked out the ones they wanted, and were riding them a few hours later! They were used throughout the 70's until around 1980 when the kids went off to college, stored in a barn in Berry KY until around 2010 when he picked them back up and took them to the same Honda dealer in Florence, got them running one last time, used them for about a year or two with his kids and then they got stuffed away when his kids went off to college. Sad story now, getting divorced, he was in the middle of clearing out the storage unit, these were WAY in the back. He said they were both running fine when he stored them, I bet I'm riding them around the neighborhood before the weekend is out. One is dated 5/70 and the other 6/70, original keys too. Also threw in a bunch of extra parts and some service records I believe. These are going to be fun to bring back to life, not sure what I'm going to do with them yet, I will most likely take them to our July 4th family reunion this year to show them off!

CT70HPair2_1.jpg


CT70HPair1.jpg
 

andrewdell19

Active Member
Ashamed???! Lol spit out a price and we'll tell you to hang your head hahaha. If you paid $1000 for the two I'd say you did well... Paid less then yeah we probably DONT want to know. Long gone are the seats when I bought three k0 bikes for $725.. it was fun fixed them up gave two to buddies and we tore it up.
 
Ashamed???! Lol spit out a price and we'll tell you to hang your head hahaha. If you paid $1000 for the two I'd say you did well... Paid less then yeah we probably DONT want to know. Long gone are the seats when I bought three k0 bikes for $725.. it was fun fixed them up gave two to buddies and we tore it up.

You find me an all original H in this condition for $500 bucks and I'll buy every single one. It was a little more than a grand, but less than 1500.
 

andrewdell19

Active Member
Yeah no kidding some people say they can find these H models all day in good condition for a few hundred... who knows if they did.

But yeah less than $1500 for the two and you are great!!!
 
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