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Discussion Starter · #1 ·
Ok, here is the deal, I have no spark on this bike. The scenario is my electric start switch at the handle bar is not functional so I added a switch back near the battery to mimic the original switch, it works just as well. Last night after finally figuring out I had a stuck float and getting the bike to run I was busy trying to adjust the carbs and the switch I added began to short together. So, while the bike was running the starter was trying to start bike because the switch was triggered for a good 20 secs. I switched the ignition off and now I have no spark. I thought perhaps the coil may be an issue so I happen to have a spare, swapped it, still no spark. I am getting voltage on each side of the coil, each side of the condensor, at the points, the fuse is fine. New plugs, points cleaned, not adjusted though, it didnt need it. It was running and firing before this occured and now I cant get spark to save my life. Solenoid is clicking fine. Any ideas here, this is just strange. Thanks.
 

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Discussion Starter · #2 ·
Another thing I would like to add is,does anybody know on the schematic for this bike where the kill switch is located? What are the wire colors for the kill switch? I cant seem to see it with these eyes.
 

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You need to work out what k series the bike is. Often the year people quote is the year the bike is registered not anything else. If the bikes anything other than a k7 there won't be a kill switch
When you say voltage to both sides of the coil are you meaning continuity between the primary and secondary windings or across them or both primary pigtails are live or something else ?
The primary should only be a circuit while the points are closed
 

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Discussion Starter · #4 ·
There is a run switch on the right side handle bar and i believed it to be a K6. With points closed there is no voltage at the points, with points open, there is 12v present at the points. The blue wire coming from the coil I am seeing 12v with the key in run position. So either side of the condensor has 12v.
 

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If you have 12 volt to the plus side of the coil. Take the coil off or to check your spare run a ground wire from the minus side of the coil to to minus on a battery. plug the plug into the lead and wrap a wire around the thread of the plug and to the minus on the battery. Take jumper wire and connect it to the plus side of the coil. Touch the jumper wire to the plus side of the battery and if the coil is good you should get a spark at the plug. If no spark the coil is bad if you have a spark then the problem is in the points or condensor.

Got the info from this site and have used it several times and it works.

Bill
 

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If it has a kill switch at the bars it's likely a k7 a check of the frame number would confirm ( cl175 8xxxxxxxxx is k7 , cl175 7xxxxxxxx is k6 ) either way if use the wiring diagram from a cb200 as it's the same as the cl175 but with a kill
The twin fire coils are more like trannsformers than standard auto coils so the test is different from above as one HT lead is + and the other is - when the coil fires .
The coil fires when the points open but only if both HT leads are able to make a circuit. If you're checking for spark with both plugs out of the head you won't get any
( How are you checking there's no spark ? )
 

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Discussion Starter · #7 ·
You are correct , it is a K7. I am checking for spark by leaving one plug in the bike connected to the coil(per usual) and the other connected to the coil and grounded(touching)to the engine fins, this is how i initially tested for spark when I first boight the bike. I was aware that both need to be grounded to complete the circuit which is why i am a bit baffled. I am just wondering what damage would have been done when the bike was trying to start while running simutaneously.
 

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Discussion Starter · #8 ·
As well, the likelihood of both coil being faulty is pretty rare, so I am fairly certain it may not be the coils, but who is to say. If Bills test is innacurate, what is a way to test the coil?
 

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Just check that there's continuity between the primary leads , continuity between the HT leads and no continuity between primary and HT or mounting points and no continuity between HT and mounting points
Check for damage to the coil and leads
that's it
You can bench test by putting a spark plug between the HT leads and running 12 v through the primary leads for a second when cuting the primary power the plug should fire
 

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Discussion Starter · #10 ·
Ok, coil checks out just fine. Last night I was trying to troubleshoot more and I have some spare parts; condensor, points so I swapped the condensor and I blew the main fuse. So, naturally I figured that condensor was faulty and I put the original one back on the bike. Well, the fuse is still blowing. I swapped the points and that is blowing a fuse. At this point, onviously I will no longer be throwing fuses in until I nail down this issue. There has to be a short to ground somewhere, but as I watch the fuse it doesnt blow right away, I crank the bike, and the fuse is hesitant to go but finally after I turn the ignition key off it will eventually give way. So now I have, no spark and a bike blowing fuses. Hmmmm...any more ideas?
 

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Discussion Starter · #11 ·
Update: if points do not touch, fuse does not blow, however, I have tried 2 sets of points, neither of them blow the fuse if not touching. Both blow the fuse if touching. The first set has noticable spark between them when touching.
 

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Well you've probably found out why the po parked it in a barn
You can hot wire it if you're still wanting to see if it will run . disconnect the battery + and unplug the black wire from the coil , use a jumper cable to connect the coil wire to the battery + , kick start the bike , if it doesn't start in 30 seconds disconnect the jumper cable and wait 30 seconds, and try again . If you leave the jumper cable connected for too long the coil will melt
If the bike won't start like this or you're still not getting spark your points are probably constantly grounding or you plug boots have no continuity or your plugs are fouled badly
 

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Discussion Starter · #15 ·
Woolah! I have spark, funky wiring at headlight. Now lets hope after i tidy this up it will remain as is. Thanks so much for your assistance!
 

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Discussion Starter · #16 ·
This may sound to be a silly question, however, I will ask. Is there an orientation designation the HT wires for the ignition coil? There are no markings stating which side goes to left or which side goes to right? I would assume the left side goes to left cyclinder and right side goes to right. I have tried it both directions and it doesnt seem to make a difference.
 

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Your engine has what's referred to as a 360° crankshaft, which means both pistons go up and down together. As a result, both coil leads fire at the same time - one is on compression stroke, the other is a wasted spark during exhaust stroke. Doesn't matter which plug wire goes on which plug, routing for the most convenient path is fine
 
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