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Discussion Starter #1
Today I was on a short ride on the 1972 CL that I recently purchased. So far I have only taken it out about 3 times, but it was well maintained by the PO and running nicely.

Today on my way back from a short ride, while pulling up to a stop light, the idle suddenly cut down and became extremely low/quiet. As I rolled to a stop the engine died. It didn't start back up right away so I walked over to the sidewalk to diagnose.

Plenty of fuel and petcock was on. Battery ok (lights working). I pulled a plug to check for spark and there was none. I figured I had a dead plug so I walked it home. Still no spark on either side with different plugs. I trimmed the leads about 1/2" because they needed it, the interior of the leads was gooey / gummy but not liquid (liquid means the coil is dead, I've read).

I tried testing the leads with a mulitmeter but it didn't show anything. Not sure if that's a legitimate way of checking the leads but I thought I'd give it a shot. I have had mystery no spark before on my 1970 CL, and that time the points wire had come disconnected from the coil. But that is not the case now. Also, this happened while riding so I would assume that means something failed, like the coil?

Finally, I checked the points and there is a bit of oil under the cover, making the gasket a bit damp. But the points themselves are dry. I read that you can check the coil by connecting it directly to the battery? But I don't think it would ever reach without removing the coil. What are my next steps? Should I drain the tank and pop it off? Or are there any other, easier checks I can do first?
 

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Discussion Starter #2
A friend suggested that I check the tail light, which I did and the bulb was out. I had checked during the ride yesterday (before it broke down) and the brake light was working/illuminated. I replaced the bulb but am still getting no spark.
 

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Test for current at the points. Roll the engine over to where the points are open then ground the points arm to the backing plate. Use a screwdriver, pocket knife, car keys anything metal will work if your stuck along side the road. If there's juice at the coil you should see a spark there and see one at the plug. Got a spark?, turn the engine again until the points are closed, then try it again. You shouldn't get a spark with the points closed, if you do you need to clean them.
 

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Discussion Starter #4
I finally got some time to work on the CL last night. I tried the points and there is current there. I can see a very tiny spark when the contact breaker opens. And when I grounded the points to the cam, it made a big spark. My guess then is that it is the condenser or the coil. The plan now was to buy a coil since they are only $4.95. If replacing the condenser doesn't give me spark at the plugs, then it would have to be the coil, correct?
 

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Start with a set of points, you wouldn't have a spark with the condenser grounded out internally.
 

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Discussion Starter #6
So you're saying if the condenser was non-functioning then I wouldn't get current at the points?

Unfortunately I already ordered the condenser this morning. I was going on the suggestion of a friend who had to replace his recently.

You're saying to replace the whole points assembly? It looks to be in good condition to me. Maybe it could just use a cleaning and gapping.
 

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Clean the points and see what happens.
 

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You just need a meter of wire to hot wire the coil from the battery ... Almost any bit of electrical wire would do. Does the horn work? It's powered by the same positive line as the coil you need to check the HT leads for spark one at a time with the other HT leads/cap/spark plug in place .
 

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Discussion Starter #9
I have checked the leads individually with the other side grounded. I will have to test the horn tonight. All the other electrical is working.
 

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Discussion Starter #10
I finally got around to working on the bike today. I have been busy with other things, and working on my 400. I was mainly dreading the crossover tube and draining the tank. Anyways I got the tank off and set off to get the new condenser installed. No idea why, but the existing one was hooked up as shown below. Points, coil, and condenser all converging, rather than the condenser being in between the points and coil. No idea how it ran this way but it did.

IMG_6229.jpg

I installed the new condenser and it didn't change anything. I hopped over to the other side of the bike to take a look at the points. When I got over there I noticed that the black wire to the coil, where it crosses through the frame, had come undone. Problem solved.
 

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Discussion Starter #11 (Edited)
So this morning I took off for work on the 175, and I was almost there when it happened again.

I accidentally got neutral instead of second, and I rev'd out a bit and then it died. So I think the vibration dislodged it. I felt under the tank and the connection was loose again. however I looked more closely and the two-part female connector there broke. I guess it was too old and brittle. So now I need to source one of those.

Found these, 3.5mm is the correct size right?

Capture.JPG
 

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That pic of the condenser looked fine ish ( except the lack of sheilding ) the condenser body needs to be grounded to the frame or engine ( the setup in your picture has it sitting on paint ) .the two lines into the stock condenser are both connected to each other so the wiring looks correct
The stock setup uses bullet connectors your setup has spades but either will do as long as they're tight and sheilded
 

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That pic of the condenser looked fine ish ( except the lack of sheilding ) the condenser body needs to be grounded to the frame or engine ( the setup in your picture has it sitting on paint ) .the two lines into the stock condenser are both connected to each other so the wiring looks correct
The stock setup uses bullet connectors your setup has spades but either will do as long as they're tight and sheilded
 

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Discussion Starter #14
Thank you for the info. I ended up wiring it all up with bullet connectors as that's what the new condenser had. The PO had the condenser bolted to a metal plate which was bolted to the frame. I went straight to the frame.

I have ordered the double female bullet connectors from 4into1. The bike is in the parking garage at work, so I had the parts shipped here and I will probably do the fix in the garage here when they come.
 

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Discussion Starter #15
A friend was able to supply a double female connector and I was able to redo the connection in the parking garage at work. Running again! woo
 
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