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Any thoughts? 2018 shadow aero 750. Took the bike for a ride tonight, it started up fine and got me to destination 1 fine, and then to destination 2 fine but when I went to start it up to head home, the lights and everything came on but push the button and it went black. No crank. I hooked up my voltage reader and it was showing 11.5. Hooked it up to my jump pack and it showed it was charging. Once it was up to about 12.6-7 I unplugged the pack and I tried to start the bike again. Nothing lit up except my quad lock charger, almost as though there was some power breakage. I still had the voltage display connected and it read the battery was charged. when I reconnected the jump pack and tried to start it started but was very weak and I heard a slight whining noise from the front section of the bike (may have just been the honda whine, but underpowered). I unplugged the pack and it died again. I’ve had ongoing problems with batteries that last less than a year and this one is about 2 months old (at least it’s still under warranty). The last time this happened it was determined that the battery was at fault because the electric and charging system checked out. I recently cleaned out and greased my ignition switch, but could it be a bad starter switch? I think this had been a lingering problem since the beginning part of this year and no mechanic can seem to figure out why it keeps doing this as it seems to start back up when a new battery has been installed. This is a problem I’ve been having since my original OEM battery that came with the bike died after 3 years. Over the last 8 months, I've been through 4 battery replacements and every time the charging system is tested, the numbers check out. The bike has no aftermarket accessories aside from the charger but that has been tested for parasitic draw.

thanks!
 

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1983 Honda vt750 Shadow
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Did you update the 3 yellow wire connector for the stater harness?
That is a weak spot and can cause low charging voltage.
When you get it running see if the voltage goes up to 13-14 volts when you rev it up to 3000 RPM.
 
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Discussion Starter · #4 ·
Did you update the 3 yellow wire connector for the stater harness?
That is a weak spot and can cause low charging voltage.
When you get it running see if the voltage goes up to 13-14 volts when you rev it up to 3000 RPM.
When I first started having this issue I used a multimeter and with a new battery, the bike would run and idle fine at around 13.5 V or so. when I'd rev and hold it wouldn't ever go over 15V. I heard that some of the 1100 had that issue and it would melt the wire connector, but hadn't heard it happening to the 750s. just out of paranoia with this ongoing problem and the battery always being blamed for it I check it regularly with a sae voltage reader and it always reads around 12.6-8. I've checked fuses before and they all seem intact. Aside from ripping the bike apart and either testing or replacing every component that could be the cause in the charging system, I haven't be able to find anyone who has had this same or ongoing issue.
 

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99' Valkyrie/North Central Indiana
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A dirty/corroded ground connection. Its happens on Valks on a occasions. If you live southern parts and or coastal area corrosion is more prevalent.
 

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1983 Honda vt750 Shadow
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The mellted 3 yellow wire connector can happen on all the models. Look for this=

Motor vehicle Electrical wiring Gas Auto part Cable
 

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The thing to check is have the meter on the battery when you hit the start button, if it drops down below 10v and the lights go out, it has no capacity. you need to charge it or replace it. A battery can have a surface charge show 12v with no load but nothing left to carry a load, if it drops more than a few tenths of a volt just turning the key on, it's suspect. And batteries are good or bad, age may not matter.
 

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Any thoughts? 2018 shadow aero 750. Took the bike for a ride tonight, it started up fine and got me to destination 1 fine, and then to destination 2 fine but when I went to start it up to head home, the lights and everything came on but push the button and it went black. No crank. I hooked up my voltage reader and it was showing 11.5. Hooked it up to my jump pack and it showed it was charging. Once it was up to about 12.6-7 I unplugged the pack and I tried to start the bike again. Nothing lit up except my quad lock charger, almost as though there was some power breakage. I still had the voltage display connected and it read the battery was charged. when I reconnected the jump pack and tried to start it started but was very weak and I heard a slight whining noise from the front section of the bike (may have just been the honda whine, but underpowered). I unplugged the pack and it died again. I’ve had ongoing problems with batteries that last less than a year and this one is about 2 months old (at least it’s still under warranty). The last time this happened it was determined that the battery was at fault because the electric and charging system checked out. I recently cleaned out and greased my ignition switch, but could it be a bad starter switch? I think this had been a lingering problem since the beginning part of this year and no mechanic can seem to figure out why it keeps doing this as it seems to start back up when a new battery has been installed. This is a problem I’ve been having since my original OEM battery that came with the bike died after 3 years. Over the last 8 months, I've been through 4 battery replacements and every time the charging system is tested, the numbers check out. The bike has no aftermarket accessories aside from the charger but that has been tested for parasitic draw.

thanks!
Quite frankly, your mechanics sounds like worthless knuckleheads. This problem should be an easy fix for a competent technician.I'm leaning toward a charging system problem, or maybe starter circuit problem. First order of business, perform visual inspection. Pay close attention to the startor connection (they are known to melt and ground out, which stops the charging. Remember this about electrical systems, the battery runs the bike, the altenator (stator) runs the battery. Check all connections, grounds and clean and tighten if needed. then fully charge the battery and test some more. Easy check on the starter relay, simply touch the heavy wire from the battery to the starter directly with a jumper, screwdriver, pliers or whatever and the starter should engage.(dont touch it, or you'll get a big shock). Check the stator output (follow the manual).Voltage regulator could be faulty, follow the test in the manal for that also. Make sure you have a good quality DVOM. You will need AC and DC voltage settings, etc.
 

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Discussion Starter · #9 ·
UPDATE**: I've continually been in denial about the electrical issues being anything other than battery related. this is three times I've had it in a shop and the positive terminal (this time) keeps showing that it's broken off from the battery before it's ever removed. They've done diagnostics, and electrical tests and everything in the system is checking out. the bike fires up when the battery is replaced. So now my question would be how could 4 batteries all have terminals that could snap off (don't know if they were all on the positive or not). before the first time that happened, I only had a quad lock charger connected directly to the battery and then after the first time, I added a jump pack. unless there is too much stress on that left side where the positive terminal is located, i have no idea why these keep failing at the terminals. Might need to start carrying a spare battery LOL. . . .or is it that I'm just lucky that way? :unsure:
 

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Discussion Starter · #10 ·
Quite frankly, your mechanics sounds like worthless knuckleheads. This problem should be an easy fix for a competent technician.I'm leaning toward a charging system problem, or maybe starter circuit problem. First order of business, perform visual inspection. Pay close attention to the startor connection (they are known to melt and ground out, which stops the charging. Remember this about electrical systems, the battery runs the bike, the altenator (stator) runs the battery. Check all connections, grounds and clean and tighten if needed. then fully charge the battery and test some more. Easy check on the starter relay, simply touch the heavy wire from the battery to the starter directly with a jumper, screwdriver, pliers or whatever and the starter should engage.(dont touch it, or you'll get a big shock). Check the stator output (follow the manual).Voltage regulator could be faulty, follow the test in the manal for that also. Make sure you have a good quality DVOM. You will need AC and DC voltage settings, etc.
Sadly, I would agree that most mechanics nowadays rely too much on computers and machines to tell them what wrong instead of looking at things themselves, but that's what they're trained for, to do and not think. Since this problem started I've gotten more familiar with the electrical functions and what runs what and how it relates to the battery but very few times have I seen the numbers when i've metered it myself that show anything is wrong. I guess I'd have to replace the battery initially to perform those tests, but that's usually where the first problem shows.
 

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Is your battery secueed so it does't slde around? Are the cables pulling the battery off to the side?
Something is causing stress on the terminals.
Or do you over tighten the lead terminals?
 

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Discussion Starter · #12 ·
Is your battery secueed so it does't slde around? Are the cables pulling the battery off to the side?
Something is causing stress on the terminals.
Or do you over tighten the lead terminals?
Yes, the battery has its own compartment with a lid on top so it's very snug. When I asked which terminals broke, they said the positive side which is the side I have both the SAE Y splitter for my qaudlock and tender output on as well as the jump pack cable. The lid doesn't sit flat on top of the battery case and I will admit I've wondered about the crowding on top of the battery, but at the same time, I wonder if the cable connectors are causing too much upward tension on the terminal when tightened. And if it's over-tightened then at highspeed vibration and potholes might be putting additional stress causing it to fraction and snap over time. so far I'm averaging about 2 months before my bike goes dead. no signs before that such as hard cranks or delayed starts. When I plug in the voltage meter and it shows 12.6 volts is that pulling the reading from the negative side if that's the case?
 

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Any voltage has to be betwwen the positive and negative terminals.
You don't get voltagef from one terminal only.
12.6 is fine with engine off but it should start climbing as soon as the alternator spins and charges. Up to 14.5 volts.
 

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Discussion Starter · #14 ·
Any voltage has to be betwwen the positive and negative terminals.
You don't get voltagef from one terminal only.
12.6 is fine with engine off but it should start climbing as soon as the alternator spins and charges. Up to 14.5 volts.
But that would be if the bike would even show power and turn over. Couldn't even get it to do that no headlight or dash. I wouldn't think that the battery would show voltage that way unless the terminal was making intermittent contact with the battery in a semi-connected state to the cells if that's even possible. When it starts and runs normally it wouldn't go above 14.75 volts on rev to raise the RPMs.
 

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If the main fuse has blown there willl be no power up to the ignition but the battery should still show on the terminals.
 

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Try a different brand of battery? Sounds like bad batteries or stress on the positive post is causing physical failure. Maybe getting over-tightened when installed? Does the seat press on the cover? I'd move the multiple connection to a different location. get a terminal block and run just one extra wire from the battery to the terminal block. I've also used longer bolts with washers/spacers under the terminals to get them to lay flat.

If the posts are not breaking, it could be a defective rectifier/regulator. If the Shunt Resistor circuitry in the rectifier goes bad, the battery becomes the resistance and can get boiled dry in months and die, No way to test other than replacing the rectifier and waiting.

And fwiw, these newer batteries do tend to die without any warning...
 

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Discussion Starter · #17 ·
Try a different brand of battery? Sounds like bad batteries or stress on the positive post is causing physical failure. Maybe getting over-tightened when installed? Does the seat press on the cover? I'd move the multiple connection to a different location. get a terminal block and run just one extra wire from the battery to the terminal block. I've also used longer bolts with washers/spacers under the terminals to get them to lay flat.

If the posts are not breaking, it could be a defective rectifier/regulator. If the Shunt Resistor circuitry in the rectifier goes bad, the battery becomes the resistant and can get boiled dry in months and die, No way to test other than replacing the rectifier and waiting.

And fwiw, these newer batteries do tend to die without any warning...
All of these batteries have been aftermarket and the shop did say that the oem what built differently with a better-grounded terminal, so if this happens again I'll probably put out the extra and stick with oem. they did take a pic of the battery to show me when I went to pick it up. It looks like it might've been slowly separated from overtightening. The soldering didn't look very solid on the terminal post. When you say a terminal block, is that like an adaptor or extender? I've thought about that just to alleviate the tension on the topside. This is the third time I've had a terminal break off, don't know if it's all been on the same side, but I guess over-tightening could be on either. The battery had a full charge before they remove it but it looked like a clean break from the terminal so there must have been just enough contact to get a voltage reading though not enough for the bike to show consistent power. It's never happened to me while riding always from a dead start in a parking lot. This is the second time in two months they've checked the charging system and replaced the battery. even they said they've never seen someone go through this many batteries without any issues in the diagnostics.
 

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All of these batteries have been aftermarket and the shop did say that the oem what built differently with a better-grounded terminal, so if this happens again I'll probably put out the extra and stick with oem. they did take a pic of the battery to show me when I went to pick it up. It looks like it might've been slowly separated from overtightening. The soldering didn't look very solid on the terminal post. When you say a terminal block, is that like an adaptor or extender? I've thought about that just to alleviate the tension on the topside. This is the third time I've had a terminal break off, don't know if it's all been on the same side, but I guess over-tightening could be on either. The battery had a full charge before they remove it but it looked like a clean break from the terminal so there must have been just enough contact to get a voltage reading though not enough for the bike to show consistent power. It's never happened to me while riding always from a dead start in a parking lot. This is the second time in two months they've checked the charging system and replaced the battery. even they said they've never seen someone go through this many batteries without any issues in the diagnostics.


I have a terminal bIt's a life changer. It's a healtech thunderbox. It os a little fused block of connections. Halightbar to it sunday as it kept blowing jeadlight fused to run my .
 

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Edit: 1st one I found,,, many different configurations, search amazon for terminal block


Edit,,, or something like this where you can cut the jumper bar and have some for key on and and battery power.

 
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