voltage regulator/rectifier

[650mark]

my stock '80 special is charging at about 13.5-14.0 when rev'd but never drops below 13.5 even at idle. new agm battery, new stator, and I believe the original regulator/rectifier. I keep the bike on a good quality battery maintainer when garaged.
all electrical has been working properly but this morning I noticed that the blinkers wouldn't work unless I rev'd the bike up. I recently replaced the original dead flasher unit with a 2-prong from the auto parts store and all blinkers have been working great until this morning. the blinkers do work correctly now (ignition on) when the bike is not running. possible bad regulator? electrical stuff kills me....

 

[XSLeo]

The idle voltage varies between bikes. Depending on what's running and how well the charging system is working it can be as low as 12 volts and still be ok.
Some people like a slow idle around 1200 rpms. this lets the battery voltage be a bit low. 1500 keeps the voltage up better at idle.
The charging system can't put out full voltage at idle, it spins to slow. At around 188 rpms it spins fast enough to be closer to full voltage. The faster it spins the more the voltage, up to what the regulator preset is.
this is why the idle voltage is given as at anywhere from 12 to 13 volts.
idle speed and load effect this. The draw from the headlight, brake light what ever draws the idle voltage down. Clean tight connections at every wiring connector improves this.
If you do a lot of around town, short trips without maintaining above about 2500 rpms will not recharge the battery very well. The e-start draws a lot out of the battery. It can take 20-30 minutes at above 2500 rpm's to fully charge the battery.
From what symptoms you mention I might suspect dirty connections. cleaning every thing might help.
The large plugs with multiple wires the wires can be pulled out of the plastic. If you look down along the side of the connector in the plastic from the connection side, you will see a small rectangle on the edge of the slot the connector fits into.
This is where the lock tab fits. If you take a stiff wire, like a paper clip, push it down into this slot you can push the lock back out of the plastic. I use a large paper clip and hammer one end a bit flat so it fits the slot better.
It may take a bit of wiggling to get the first one out. Once you get one apart you will better see how they work. Once you see this the rest will be easy.
Clean how every you see best. I use small files, sandpaper and electrical contact cleaner.
On the male part of the connection you can gently squeeze the clip so it has a snug fit on the female part.
A dab of dielectric grease help keep the connections from corrosion.
I might also check the brushes, they may be short. Brushes as they age not only do the carbon part wear away the spring can get weak. Weak spring can lead to a weak connection between the brushes and rotor.
Another thing, your 80 has the four fuse block under the seat. It has round glass fuses. Round glass fuses were crap when new, 35 years hasn't made them better.
The main thing is that the clips that hold the fuses corrode a bit. this increases the resistance of current flow through them. This extra resistance creates heat, heat weakens the clips. this increase the resistance, creates more heat. You see where this leads. Eventually they get so weak they break.
Best to replace the old glass fuses with modern blade type fuses. Many ways to do this, Easy way is to get four inline fuse holders.
Do one at a time. Cut the wires off the fuse holder. Splice in a new fuse holder. I use heat shrink tubing, cut a piece slip it on the wire before you solder. Once soldered slide the tubing over the joint. Use a heat gun or hair drier to heat the tubing to shrink it tight. Repeat with each set of wires. This isn't real neat but very functional.
There are fuse blocks that can be used, a bit neater but cost more.
Leo

 

[retiredgentleman]

my stock '80 special is charging at about 13.5-14.0 when rev'd but never drops below 13.5 even at idle. new agm battery, new stator, and I believe the original regulator/rectifier. I keep the bike on a good quality battery maintainer when garaged.
all electrical has been working properly but this morning I noticed that the blinkers wouldn't work unless I rev'd the bike up. I recently replaced the original dead flasher unit with a 2-prong from the auto parts store and all blinkers have been working great until this morning. the blinkers do work correctly now (ignition on) when the bike is not running. possible bad regulator? electrical stuff kills me....

Good advice from Leo.

If your bike's battery voltage varies from 13.5 volts to 14.0 volts, be happy! As long as it goes up to 14 volts, as you drive along the road, the battery will maintains its charge just fine. In a perfect world 14.1 or 14.2 volts is better for your battery, but 14.0 volts is still quite good.

You do not need a "maintainer", as long as you have a healthy battery, and you drive
your bike once every 2 weeks or so. If your bike sits unused for long periods, then perhaps the battery will lose its charge. I've had my bike for 9 seasons now, and I have never used an external charger during the riding season.

These bikes are meant to be driven often. Get out and drive your bike at least once per week/2 weeks and you will never need to use a "maintainer".

Its normal for the blinkers to not blink, if the voltage is around 13 to 13.5 volts. That's just because of the large current required by the stock type flasher to make it flash.
Here's a simple solution that will allow the blinkers to work even if the idle speed goes down to 1100 rpm or lower, and voltage drops off to12 volts or less. Buy yourself a Tridon HD12 flasher unit. It does not rely on the high current flow, it uses capacitor charge time instead. Another safety benefit, is if one turn bulb burns out, it will still flash the other single bulb. Its a 2 pin flasher, and just plugs into your harness.

 

[650mark]

thanks for the input. like I said, electrical stuff gets the better of me almost every time but I always learn something from you guys. this is my 5th xs650, but all the others have gotten new wiring harnesses, stators, reg/rec's, etc. each time I restored one. this is my first one with all oem stuff so I guess after 35 years some of the components might need some attention. i'll clean and check all the connections this week, but I just wanted to be sure that the system wasn't overcharging. btdt on one of my other bikes and most everything got fried. thanks for the tips