Ignition system questions on Buddy 50
Posted: Sat Mar 30, 2024 1:19 am
I guess I'll just drop my specific questions right up front, and then if you want to know the full story you can read on about the diagnostic hell I am currently going through.
-I can't find specs on the pickup wire (blue/yellow coming off the stator). I'm reading only 0.1~0.2V while cranking the starter. Is that too low or is it fine? Should I try to adjust the gap of the pickup?
-According to the wiring diagram in the service manual I am looking at (http://modernbuddy.com/pdf/buddy50_service_manual.pdf), that blue/yellow wire goes directly into the CDI. The thing is, my CDI only has 4 wires going into it - red, black, red/black, and blue/white. I looked to see if the blue/yellow had somehow escaped from the connector, and I even cut back the tape a little ways on that pack of wires, but couldn't find it. It doesn't look like it was ever there. Is that normal? Also on a related note, while I was testing for voltage from the ignition coil terminals, I was getting a little blip of something there but then looked back and noticed my stator was still disconnected from when I was looking at it earlier. It spooked me at first, thinking how can I be getting voltage from the CDI output if the trigger wire isn't plugged in??? But considering the other end of that blue/yellow wire is MIA anyway, it makes me think that maybe the bike somehow just doesn't use that wire to determine timing for some reason. It doesn't make sense to me, but I'm in over my head here.
So if you want the long story - back around January I took the bike out of town to visit a friend. When I went to leave, the bike wouldn't start. It would crank, but not fire. Sure it was cold out, but I've started it in worse weather without a problem. I ended up having to leave the bike there overnight and my friend took me home. The bike has 13k miles on it and this is the first time it's ever stranded me like that. The next day I tapped another friend who has a truck, and she took me to pick up the bike. For shits and giggles I cranked the starter, and it started right up, so I just rode it home and chalked it up to the cold and maybe the weird incline of my friend's driveway where I had parked it.
Maybe a week later, I rode the bike to church, and came out after service, and it wouldn't start again. This time I had to push it back home, uphill, in the cold, through the snow, and that reeeeaelly sucked. When I got it home I pulled the spark plug and it looked pretty fouled with crusty carbon buildup and also what looked like a bit of dirty black oil residue. So I walked to Auto Zone and bought a new plug, and it started up immediately. I couldn't remember the last time it had been replaced so I didn't think much of it and figured I had fixed the issue.
And then it was fine up until last week, when it stranded me for a third time, and I had to push it home again. I pulled the plug, and it looked blacker than I had expected for a plug that had just been changed, and thought maybe there's something else going on that I should be looking at. I went to Auto Zone and bought another new plug, but this time it didn't come back to life and I haven't been able to get it to fire since then.
I have spent all week tearing it to pieces in my garage trying to pin down a diagnosis but can't figure it out. The battery is not healthy, but I normally kick start. It does sit above 12V and it is enough to run the lights and get a few solid cranks out of it before needing a charge. The electric starter works fine, so I'm assuming I can rule out the ignition switch and killswitch, but someone feel free to tell me if I'm wrong on that. I'm getting 30~50 volts on the red/black (ignition charge?) wire when kicking/cranking the starter, so I would think that should be enough to charge the CDI. My ignition coil is looking a little worse for wear. The resistance readings are about 8.9k on the cap, and 0.1 ohms on the primary leads. Although I couldn't find exact manufacturer specs for the Buddy, other generic information and forum posts I found around the web suggests this is about normal for a coil on one of these machines. I am also getting a blip of a voltage reading across the ignition coil terminals when cranking the starter. My meter reads randomly anywhere between a fraction of a volt and maybe 4 volts. I am getting similar readings from the cap. Now according to what I have read, you need a tool called a peak voltage adapter to read those momentary discharges from the CDI to the ignition coil. Unfortunately I don't have one of those, so the best I can say is "it's doing something" but not resulting in a spark. I have tested the spark plug itself (well, all 3 of them that I now own) in the cap by holding the plug against the engine or another ground while cranking the starter, but I have not seen it spark. Whatever other issues may exist, I really need to get the bike running at least so I can go grocery shopping. I'm hoping if I throw a CDI + coil at it, along with the new spark plug, it will fix the problem... but I have not been able to find a smoking gun to say that either of those components are definitely bad.
Last year I had the regulator/rectifier go bad and I only found out when my battery went flat and my lights stopped working. The dealer sold me another bad one for like $40, which instead overcharged my battery and blew my headlight. I took it back to the dealer and told them it was bad, they charged me a restocking fee to return it, and also charged me for a new headlight, and then I assume they put the damn rectifier back in the stock bin to sell to the next poor unsuspecting sap. So I figured if I'm going to be rolling the dice on unreliable parts, I might as well just try one of the $8 ones from amazon instead of letting the dealer rip me off. I bought this along with a volt meter that I wired in place of the USB port so I could keep an eye on it, and that has worked fine ever since. The whole incident has me wondering what other latent electrical failures might have been caused by that whole overvolting episode though.
If taking the bike to a real mechanic was an option, I would be all over it. I could go on a whole rant about the dealer, but bottom line is it's just a proven waste of time and money dealing with them. So I am basically on my own with this bike. I've already been down there to try and buy a coil + CDI, but they didn't have either of them so I am going to probably have to order from Scooter Dynasty and pay up the ass for fast shipping.
-I can't find specs on the pickup wire (blue/yellow coming off the stator). I'm reading only 0.1~0.2V while cranking the starter. Is that too low or is it fine? Should I try to adjust the gap of the pickup?
-According to the wiring diagram in the service manual I am looking at (http://modernbuddy.com/pdf/buddy50_service_manual.pdf), that blue/yellow wire goes directly into the CDI. The thing is, my CDI only has 4 wires going into it - red, black, red/black, and blue/white. I looked to see if the blue/yellow had somehow escaped from the connector, and I even cut back the tape a little ways on that pack of wires, but couldn't find it. It doesn't look like it was ever there. Is that normal? Also on a related note, while I was testing for voltage from the ignition coil terminals, I was getting a little blip of something there but then looked back and noticed my stator was still disconnected from when I was looking at it earlier. It spooked me at first, thinking how can I be getting voltage from the CDI output if the trigger wire isn't plugged in??? But considering the other end of that blue/yellow wire is MIA anyway, it makes me think that maybe the bike somehow just doesn't use that wire to determine timing for some reason. It doesn't make sense to me, but I'm in over my head here.
So if you want the long story - back around January I took the bike out of town to visit a friend. When I went to leave, the bike wouldn't start. It would crank, but not fire. Sure it was cold out, but I've started it in worse weather without a problem. I ended up having to leave the bike there overnight and my friend took me home. The bike has 13k miles on it and this is the first time it's ever stranded me like that. The next day I tapped another friend who has a truck, and she took me to pick up the bike. For shits and giggles I cranked the starter, and it started right up, so I just rode it home and chalked it up to the cold and maybe the weird incline of my friend's driveway where I had parked it.
Maybe a week later, I rode the bike to church, and came out after service, and it wouldn't start again. This time I had to push it back home, uphill, in the cold, through the snow, and that reeeeaelly sucked. When I got it home I pulled the spark plug and it looked pretty fouled with crusty carbon buildup and also what looked like a bit of dirty black oil residue. So I walked to Auto Zone and bought a new plug, and it started up immediately. I couldn't remember the last time it had been replaced so I didn't think much of it and figured I had fixed the issue.
And then it was fine up until last week, when it stranded me for a third time, and I had to push it home again. I pulled the plug, and it looked blacker than I had expected for a plug that had just been changed, and thought maybe there's something else going on that I should be looking at. I went to Auto Zone and bought another new plug, but this time it didn't come back to life and I haven't been able to get it to fire since then.
I have spent all week tearing it to pieces in my garage trying to pin down a diagnosis but can't figure it out. The battery is not healthy, but I normally kick start. It does sit above 12V and it is enough to run the lights and get a few solid cranks out of it before needing a charge. The electric starter works fine, so I'm assuming I can rule out the ignition switch and killswitch, but someone feel free to tell me if I'm wrong on that. I'm getting 30~50 volts on the red/black (ignition charge?) wire when kicking/cranking the starter, so I would think that should be enough to charge the CDI. My ignition coil is looking a little worse for wear. The resistance readings are about 8.9k on the cap, and 0.1 ohms on the primary leads. Although I couldn't find exact manufacturer specs for the Buddy, other generic information and forum posts I found around the web suggests this is about normal for a coil on one of these machines. I am also getting a blip of a voltage reading across the ignition coil terminals when cranking the starter. My meter reads randomly anywhere between a fraction of a volt and maybe 4 volts. I am getting similar readings from the cap. Now according to what I have read, you need a tool called a peak voltage adapter to read those momentary discharges from the CDI to the ignition coil. Unfortunately I don't have one of those, so the best I can say is "it's doing something" but not resulting in a spark. I have tested the spark plug itself (well, all 3 of them that I now own) in the cap by holding the plug against the engine or another ground while cranking the starter, but I have not seen it spark. Whatever other issues may exist, I really need to get the bike running at least so I can go grocery shopping. I'm hoping if I throw a CDI + coil at it, along with the new spark plug, it will fix the problem... but I have not been able to find a smoking gun to say that either of those components are definitely bad.
Last year I had the regulator/rectifier go bad and I only found out when my battery went flat and my lights stopped working. The dealer sold me another bad one for like $40, which instead overcharged my battery and blew my headlight. I took it back to the dealer and told them it was bad, they charged me a restocking fee to return it, and also charged me for a new headlight, and then I assume they put the damn rectifier back in the stock bin to sell to the next poor unsuspecting sap. So I figured if I'm going to be rolling the dice on unreliable parts, I might as well just try one of the $8 ones from amazon instead of letting the dealer rip me off. I bought this along with a volt meter that I wired in place of the USB port so I could keep an eye on it, and that has worked fine ever since. The whole incident has me wondering what other latent electrical failures might have been caused by that whole overvolting episode though.
If taking the bike to a real mechanic was an option, I would be all over it. I could go on a whole rant about the dealer, but bottom line is it's just a proven waste of time and money dealing with them. So I am basically on my own with this bike. I've already been down there to try and buy a coil + CDI, but they didn't have either of them so I am going to probably have to order from Scooter Dynasty and pay up the ass for fast shipping.