1974 CT 90 no start.

The 208

The 208

Active Member
I got this bike running about 18 months ago. The owner keeps it at his summer cabin. It wont start this summer. It has spark, 120 psi compression and I checked valves. I give it a shot of ether and no sign of life. I put a new spark plug in it, and a shot of ether and it started for about 2 seconds. I put the choke on, turned on the gas and nothing. Another shot...nothing.

A couple thing to note. The green neutral light doesn't come on unless you have on/off switch in the off position. However after trying to start it a bit, the light will be on when the switch is on.

He also the 1969 Trail 70 that I got running for him too. That one wont start either. He said his 12 year old grandson had ridden the heck out of it, so.....no telling. I haven't messed with that one yet.
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The 208

The 208

Active Member
Update. After charging the battery, it still didn't start. I checked the points gap ( I kinda forgot these old bikes have points) it checks out at .012, which I think is ok. But I cleaned them a piece of sand paper and it fired right up.

So onto the 70. I'm not sure on the year of this one. My notes from previous work says 1969. And I ordered parts for it. A stator rebuild kit, flywheel and cover, air filter and carb kit. Does that look like a 1969 to the sharp eyed ones?
I remember somebody poking fun at the Lipton tea lid. LOL Its still there.

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The 208

The 208

Active Member
Ok, so I got to work on the 70. No spark. I cleaned the points and the gap seems to be a bit big. I think the spec is .012-.016. This one comes out at about .018. I read a post from @kirrby in another thread that he said if the gap is off even a smidge it won't start. So, the gap is first, but this wire is hanging loose and I'm not sure where it goes. I found this pic of a ignition off a ct70 and the black wire is clearly not connected to anything. Any ideas???

Copy/paste that link and the pic comes right up. Thanks!

 
The 208

The 208

Active Member
The 90 is good. I've ridden it out to the mailbox a few times. Its getting picked up today and I was hoping to have the 70 ready to go.
 
MiniBike Mike’s Garage

MiniBike Mike’s Garage

Well-Known Member
The 208 said:
Update. After charging the battery, it still didn't start. I checked the points gap ( I kinda forgot these old bikes have points) it checks out at .012, which I think is ok. But I cleaned them a piece of sand paper and it fired right up.

So onto the 70. I'm not sure on the year of this one. My notes from previous work says 1969. And I ordered parts for it. A stator rebuild kit, flywheel and cover, air filter and carb kit. Does that look like a 1969 to the sharp eyed ones?
I remember somebody poking fun at the Lipton tea lid. LOL Its still there.

View attachment 79252
Click to expand...
Technically, Honda did not designate a model year to the CT70’s until the 1976 model. What you have is called a K0 (K Zero), which is the first model of CT70. The K0 line was built from 6/69 to 8/71. Any time you order parts, do NOT search by year, rather, search for K0 parts.
What is the VIN on this bike? Is the tag on the neck tube silver or black? It kinda looks like the stamped number on the frame is: CT70-103xxx, but it’s hard to read. If so, the bike is an early silver tag, built at the end of 6/69 or early 7/69.
 
N

-Nate

Active Member
The points gap must never exceed .016" and the bike will run batter at .012" .

EVERY TIME you change the gap or clean the points the timing wil move and MUST BE CHECKED AND ADJUSTED TO THE "F" MARK .

Nice to see the CT70 in good shape and still running .
 
The 208

The 208

Active Member
MiniBike Mike’s Garage said:
Technically, Honda did not designate a model year to the CT70’s until the 1976 model. What you have is called a K0 (K Zero), which is the first model of CT70. The K0 line was built from 6/69 to 8/71. Any time you order parts, do NOT search by year, rather, search for K0 parts.
What is the VIN on this bike? Is the tag on the neck tube silver or black? It kinda looks like the stamped number on the frame is: CT70-103xxx, but it’s hard to read. If so, the bike is an early silver tag, built at the end of 6/69 or early 7/69.
Click to expand...
Thank you, that's good to know. Ya, the tag is silver. I don't remember how I determined a 69, but that's whats in my notes from the last time it was here. Last time I ordered a flywheel, stator rebuild kit, air filter, and a the flywheel cover, and maybe a few other things. I set the points gap at around .013. .014 is a tight fit. I should be in the park. But what is that black wire for? It's not connected to anything. Even in the link that I posted above.
 
MiniBike Mike’s Garage

MiniBike Mike’s Garage

Well-Known Member
The 208 said:
Thank you, that's good to know. Ya, the tag is silver. I don't remember how I determined a 69, but that's whats in my notes from the last time it was here. Last time I ordered a flywheel, stator rebuild kit, air filter, and a the flywheel cover, and maybe a few other things. I set the points gap at around .013. .014 is a tight fit. I should be in the park. But what is that black wire for? It's not connected to anything. Even in the link that I posted above.
Click to expand...
Not sure why it’s black, but looks like neutral indicator wire.
 
The 208

The 208

Active Member
I ohm tested the coil. Shouldn't I have some continuity between the spark plug wire and the mounting frame of the coil? I have zero ohms.
 
N

-Nate

Active Member
If it connects to the points it's the shut off circuit ~ Hondas early "Energy Transfer" (magneto) ignitions stopped spark by grounding them .
 
The 208

The 208

Active Member
So, finally figured out the problem. That bare copper wire was broken under the solder. DOH! Resoldered everything gave it a shot of starting fluid, the gas tank is off, and it fired up for a couple seconds.
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