No Spark, help please!!
- Thread starter daveswfla53
- Start date
Well I’ve made some really good discorveries. I can confirm that the magneto does produce electricity. I put a multimeter to the blue and black wires and got a very bouncy voltage. Then I went from the blue wire from the magneto to the sides of the hole for the spark plug and got a voltage. This means there’s has to be something wrong on the cdis side. Once again I know the spark plugs are fine.
a video only shows one way to do one thing in one situation - unless everything is just right, a video is little help
understanding is required, which means reading and thinking and sometimes some experience with knowing what you're seeing when you look at the thing
you mentioned; "multimeter to the blue and black wires and got a very bouncy voltage. Then I went from the blue wire from the magneto to the sides of the hole for the spark plug and got a voltage"
I have no idea if that means you have voltage coming out of CDI or if you have voltage coming out of mag to ground - one means you have a bad plug wire or cap, while the other means you have a bad CDI. It sounds like you're just circling around and around the problem without ever seeing the path that will take you to the solution.
understanding is required, which means reading and thinking and sometimes some experience with knowing what you're seeing when you look at the thing
you mentioned; "multimeter to the blue and black wires and got a very bouncy voltage. Then I went from the blue wire from the magneto to the sides of the hole for the spark plug and got a voltage"
I have no idea if that means you have voltage coming out of CDI or if you have voltage coming out of mag to ground - one means you have a bad plug wire or cap, while the other means you have a bad CDI. It sounds like you're just circling around and around the problem without ever seeing the path that will take you to the solution.
Sorry for my ignorance lol I’m only 15 and even though I am pretty smart with this kind of thing this is a new thing for me. What I was trying to say is that I can confirm that the magneto to ground is working. As mentioned earlier the spark plug is working so that leaves the 4 cdis I have that don’t work for an unknown reason. But at this point in time I am trying to figure out why the cdis don’t work. You are right about me bouncing around and I’ll try to stop that and actually find a solution. In terms of finding out why the cdis dont work I have no clue what to do. No one in my area has one of these bikes so it’s just me and the internet or a small engine repair guy I’ll have to bring this to which I’m trying to avoid but at this point it’s the next step.
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my path to try and find the solution is to troubleshoot and figure out what is causing a lack of spark. I want to narrow it down until I know what the problem is then I can fix it. Now I know what the problem is the cdi so I’m going to figure out why the cdi is not working and then once I know that I’ll get a solution.
I find it possible, but VERY hard to believe that 4 CDIs are all bad - esp. when last week, one started working again for no reason.
I once saw a bad magneto in which the plates weren't riveted properly so that it would spark for a few minutes, then stop due to heat from internal arcing - this is very unusual tho. More common is a mag with a bad ground connection from coil to armature that sometimes reads OK, but fails from just the bit of shaking when trying to start the motor, but this is also a bit rare.
Here at the shop with parts on the shelf, I'd take 10min and replace both just to see what happened.
I once saw a bad magneto in which the plates weren't riveted properly so that it would spark for a few minutes, then stop due to heat from internal arcing - this is very unusual tho. More common is a mag with a bad ground connection from coil to armature that sometimes reads OK, but fails from just the bit of shaking when trying to start the motor, but this is also a bit rare.
Here at the shop with parts on the shelf, I'd take 10min and replace both just to see what happened.
Well the thing is that I tried mag number 1 which is what I uses to actually start the motor then when it died I connected all the cdis I have and bone I them got spark with mag 1 so I changed to another working one I had, cycled all the cdis and still no spark. Now if I try to hammer in the rivets because they all stick out a little will that change anything? Now if the shaking is the problem how can I fix that?
some mags have 4 rivets, some have 6 rivets and some have 4 rivets and 2 connecting posts - in 10 years, I've only seen one that failed due to loose rivets and in 10 years, I must have seen well over 1000 of them
I have a 20 ton press to deal with things like that and wouldn't advise trying to fix it with a hammer.
If you look on ebay, you can probably find someone selling CDI & mag as a pair for under $10 - I'd suggest getting 2 sets at that price.
I have a 20 ton press to deal with things like that and wouldn't advise trying to fix it with a hammer.
If you look on ebay, you can probably find someone selling CDI & mag as a pair for under $10 - I'd suggest getting 2 sets at that price.
I would suggest you go back to the basics and check out this thread:
https://motorbicycling.com/threads/so-your-ht-bicycle-engine-wont-start-well-lets-take-a-look.35090/
Go through it and you will likely find the problem. It's probably going to turn out to be something simple. Hard to believe you could end up with a bunch of dead parts.
Good for you that you are working through it and not giving up. A simple thing to try first is to disconnect the kill switch.
https://motorbicycling.com/threads/so-your-ht-bicycle-engine-wont-start-well-lets-take-a-look.35090/
Go through it and you will likely find the problem. It's probably going to turn out to be something simple. Hard to believe you could end up with a bunch of dead parts.
Good for you that you are working through it and not giving up. A simple thing to try first is to disconnect the kill switch.
I looked at the thread aND it had very useful infomation. The mag seems to be OK judging my the things it said but once again all cdis I have are not showing any readings in any situation. I also haven't even touched the kill switch and am certainly not connecting it anywhere.
You know if after all this there's still just no spark... maybe the two of you just shouldn't go out anymore.
But seriously folks,
Have you considered going elsewhere for your sparks so to speak? As in maybe replacing your magneto with hall effect sensor and going the on-board power & modern CDI route? Shortly after I installed my kit I had an experience that was at least superficially very similar to yours; 15-ish minutes of riding followed by 15 hours of troubleshooting, but in the end, a new mysterious black box CDI whose magic hadn't leaked out solved my issue. I read the first page of this thread and skimmed the others, so forgive me if you've already done this, but have you tried moving all the known-to-work ignition components off of one of your other bikes to this one? Can you think of any part, no matter how trivial (including the plug boot assembly, the plug itself, and even the magneto screws) that has been with you from the onset of the problem? Is the black wire PROPERLY soldered to the magneto core and do you for sure have continuity from black to block?
Although I have no proof of it occurring or indeed even being possible, I also theorize that if a plug were sufficiently carbonized it may be possible for a sort of "long short" circuit to begin competing with the gap and even eventually have impedance low enough to interfere with most sparks.
Yesterday I actually decided to dispense with the black wire altogether to make it easier to run the blue inside a length of tubing for water-tightness. Right now the CDI ground is tied to the lock washer on the exhaust manifold and everything seems to be playing nice.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth."
-Data
(I'm kidding. It was Sherlock or something.)
But seriously folks,
Have you considered going elsewhere for your sparks so to speak? As in maybe replacing your magneto with hall effect sensor and going the on-board power & modern CDI route? Shortly after I installed my kit I had an experience that was at least superficially very similar to yours; 15-ish minutes of riding followed by 15 hours of troubleshooting, but in the end, a new mysterious black box CDI whose magic hadn't leaked out solved my issue. I read the first page of this thread and skimmed the others, so forgive me if you've already done this, but have you tried moving all the known-to-work ignition components off of one of your other bikes to this one? Can you think of any part, no matter how trivial (including the plug boot assembly, the plug itself, and even the magneto screws) that has been with you from the onset of the problem? Is the black wire PROPERLY soldered to the magneto core and do you for sure have continuity from black to block?
Although I have no proof of it occurring or indeed even being possible, I also theorize that if a plug were sufficiently carbonized it may be possible for a sort of "long short" circuit to begin competing with the gap and even eventually have impedance low enough to interfere with most sparks.
Yesterday I actually decided to dispense with the black wire altogether to make it easier to run the blue inside a length of tubing for water-tightness. Right now the CDI ground is tied to the lock washer on the exhaust manifold and everything seems to be playing nice.
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth."
-Data
(I'm kidding. It was Sherlock or something.)
