Slow battery drain

raimitm said:
I followed the guide and found a few things. Let me know if this shows the source of the problem.

When idling, V goes up to 12.3 then back down and up inconsistently, doesn't go up past that mostly stays around 12
Slap test is very weak with the case on. I took off the case and found this circle which seems to be the only part of the rotor
that is magnetized.

View attachment 122904

I unplugged the stator connector and none of the male ends make a connection when touching 2 of the 3 ends with a multimeter.

On the female side, only the bottom receptor makes a circuit with the + battery terminal.

Tested the regulator connector and that is fine. Tried revving while the regulator is bypassed to ground and no difference.

Another thing is I cant get a read on the rotor, seems like the rotor is no good.
Click to expand...

Hi raimi,
that little round copper disc is the permanent magnet that triggers the ignition.
The rotor is an electromagnet that is only magnetized when the ignition is turned on and feeds it 12V DC from the battery.
Once you can get at both slip-rings you should see at least 4 Ohms resistance between them and no current at all between
either ring and the rest of the rotor.
 
fredintoon said:
Hi raimi,
that little round copper disc is the permanent magnet that triggers the ignition.
The rotor is an electromagnet that is only magnetized when the ignition is turned on and feeds it 12V DC from the battery.
Once you can get at both slip-rings you should see at least 4 Ohms resistance between them and no current at all between
either ring and the rest of the rotor.
Click to expand...

Good to know about the magnet disc in the rotor, thanks.
I'm getting no Ohm resistance between the rings. In the pic it might look like i'm off the rings,
but i've tried it in different spots of the rings and no luck. Ive seen low resistance in videos but usually theres something
 
Going off your last pic.... if your probes are indeed touching the rings, your rotor's open. Should be about 5 ohms. You're gonna need a new one. Judging from the looks of it, I seriously doubt the dealer replaced it... fwiw.
raimitm said:
Also tested continuity and no beep.
Click to expand...
The "beep" function doesn't check continuity. That's a common misunderstanding with meters. That function checks "voltage drop." Mainly for checking diodes but useful for other things also.When checking resistance... continuity... whatever you want to call it, you need to keep the rotary switch inside the outline with the "ohms" symbol.
 
Shifter and foot peg have to come off. I set the allenhead screws in a a pattern while taking them off so as to put them back in correctly, there are a couple different lengths. Watch you don't lose a small ball bearing that is in the clutch worm gear.
When the rotor puller comes in and you get the rotor in hand, test probe it again. If it reads open then take a look at the back, as sometimes the end of the winding may have come undone, un soldered.

With the side cover off, check for any wires being damaged by the chain, as in Ggggary's post.
 
Got the cover off and looks like the chain did do a little damage to the orange wire that comes from the stator.
The 3 white wires from the stator were properly routed and weren't damaged.
I took the stator off completely and tested the rotor while exposed, in many places of the slip rings, still no resistance reading.
I'll be ordering a new rotor, but I'm not sure if i have a problem with the stator as well.
The right brush to stator case gives a resistance reading. Each of the 3 white wires at connector to the engine gives a reading
that doesn't stop at a number. I've seen videos saying this means the stator is going bad? Will it work at all or just less efficiently?
When i test between the 3 white wires, theres a connection.
I'm going to replace the rotor for now, but could a problem with the stator damage the new rotor i put in?

Resized_20180810_111340.jpeg
 
JimD54 said:
Going off your last pic.... if your probes are indeed touching the rings, your rotor's open. Should be about 5 ohms. You're gonna need a new one. Judging from the looks of it, I seriously doubt the dealer replaced it... fwiw.

The "beep" function doesn't check continuity. That's a common misunderstanding with meters. That function checks "voltage drop." Mainly for checking diodes but useful for other things also.When checking resistance... continuity... whatever you want to call it, you need to keep the rotary switch inside the outline with the "ohms" symbol.
Click to expand...

Yeah looks that way. Weird thing is that it was fine for a few hours before the battery died. Now the battery dies fast. Seems like it was charging then failed at some point.
 
Just a update-
Replaced the rotor, bike started charging to 13.5, thought it was fine.
Rode the bike downtown, about 30 min. Started stuttering on the highway, wouldn't go past 40 mph,
made it off the highway before the battery went down to around 10 and wouldn't start.
Took the battery home, charged it and brought it back to the bike. Barely got it started up, idles fine
but I can't rev it at all, the bike starts stuttering like its going to die as soon as i rev it. I read that this is
connected to the alternator not working as it should.
Just ordered a used but tested stator and regulator.
That should take care of it.
 
I've now replace the rotor, stator and regulator. I still have the problem where as soon as I rev, the bike
sputters and starts backfiring. This problem completely goes away when I unplug the regulator. Changing
the regulator didn't fix this, but it seems like it has to do with the regulator. Does this mean the wires from
the connector is bad?
Also, when the bike is turned on and I check the voltage, there is a .1 drop every second. I'm guessing theres multiple bad wires?
The voltage from battery to positive brush drops 1.0 V
 
Yes, I think you have some weird problem like the wiring is not like you think it is because all the evidence does not add up.
Purely from your latest post, it suggests you have a shorted rotor (or rotor wiring) because you can't get a volt drop like that on good wires and connections without serious (too much) current flowing, and something is draining your battery too fast.
It's all very well making static measurements on individual components, but what you really need to know is how much current is flowing into your rotor as a system i.e. wiring, windings, brushes, regulator. I hesitate to suggest using your multimeter as an ammeter because (I mean no disrespect) it seems you're not entirely at ease with using your meter and you're likely to blow something up, if only the fuse in the meter. And you probably won't get a stable reading anyway.
Did you buy your 6V 6W bulb yet? (see my earlier post). You can connect it into either of the wires from the rotor - series circuits don't know what order things are connected in. One way or another this will tell you if you have a healthy amount of current flowing into your rotor when its running. If you have enough current to drop 1.0V in good wiring, it will pop straight away and you'll have learnt something useful (buy a few bulbs!).
 
Do not worry about the heat resistance for magnets. All you want is a common shiny Neodymium magnet to glue over the top of the old magnet. I forget the size of the current magnet, 5 or 6mm diameter, just get the same diameter and try to get a 1mm or 0.5mm thick magnet. I used 0.5mm in the past because they were easy to get in the UK (If the magnet is too thick it will not have sufficient clearance when the stator is put back on).When you place it on the old magnet it will align the correct way automatically i.e. it will stick or flip over and then stick. I used Araldite 15 minutes after giving the old magnet and immediate surrounding area a sand to clean it up. Put some glue on the old clean magnet then stick the new magnet on top. Make sure there is some glue around the edges of the new magnet so that it is glued on well.

Have fun!
 
raimitm said:
Awesome, thanks! Looks like the same exact problem, i got my new rotor from mikesxs too. Do you know where to find high temp earth magnets? I found the right size but can't find any that are heat resistant. Not sure if the regular ones will lose magnetism.
Click to expand...

Send me a self addressed stamped envelope and I'll send you one to fit. Had to buy a dozen to get one some years ago. Rare earth magnets. Your call.
 
I just looked up the temperatures for Neodymium magnets. The first column is the Type, the second is the Maximum Working Temperature and the third is the Curie Temperature:
N 80°C 310°C
M 100°C 340°C
H 120°C 340°C
SH 150°C 340°C

Note: There are other higher working temperature grades. Some consider the maximum working temperature of the N types to be more like 60 Celsius

The Curie temperature is high for all. Ideally we should use an H or SH type or higher. However the maximum working temperature is where some of the magnetic strength is permanenty lost, not all. I would guess that an N type would be OK if that is all that's available but if the ignition problems returned once the engine had warmed up then I would look for an alternative type. The rotor probably gets close to 100 Celsius, if not a little higher, certainly too hot to put your finger on.
 
Paul Sutton said:
I just looked up the temperatures for Neodymium magnets. The first column is the Type, the second is the Maximum Working Temperature and the third is the Curie Temperature:
N 80°C 310°C
M 100°C 340°C
H 120°C 340°C
SH 150°C 340°C

Note: There are other higher working temperature grades. Some consider the maximum working temperature of the N types to be more like 60 Celsius

The Curie temperature is high for all. Ideally we should use an H or SH type or higher. However the maximum working temperature is where some of the magnetic strength is permanenty lost, not all. I would guess that an N type would be OK if that is all that's available but if the ignition problems returned once the engine had warmed up then I would look for an alternative type. The rotor probably gets close to 100 Celsius, if not a little higher, certainly too hot to put your finger on.
Click to expand...

Thanks for the info, I was able to find the N type and it's got my bike charging and revving. If the problem returns I'll be looking for the H or SH
 
Paul Sutton said:
Glad to hear you sorted it all. Now what is your next project?
Click to expand...

I'm going to replace the battery because there's a sudden drop in volts as soon as I turn the key, and the voltage is still
dropping when I'm not revving. Going to look for any shorts next.
 
Your battery sounds normal. What a lot do is buy a small voltmeter and permanently mount it on their bike. Example:
Meter.jpg
This is wired -ve to chassis and +ve to the power from the ignition switch so when you switch the ignition they can monitor how their electrics are doing as they ride. I have a rectangular version from China but there are 100s of varieties available. When I switch on my ignition, without starting the engine, the voltage reads approximately 12.5V and this drops in a similar manner to what you have described above. This is due to the current drain by the ignition system and the tail lights. If I wait about 1minute the voltage will be showing about 11.6V. I try to start the bike as soon as the ignition switch goes on and then I will see the system jump to about 13.5V as the alternator gets going. While riding I see a fairly constant 14.4V which tells me the charging system is working.

At startup when the engine is cold and not idling at 1200 rpm you may notice the voltage will drop to about 11.3V but as soon as you increase the revs to 1200 - 1500rpm the voltage should climb to 13 - 14V. Some owners bikes give the full charging voltage of 14.2 - 14.7V at 1200rpm - They are lucky!

If your battery will run the starter motor then it is good - But you have an issue to address there with the broken switch. I think your battery is fine.
 
Sounds like I need a voltmeter, especially using the rare earth magnet. It already came off once. Wondering if I should pick up the extreme heat JB weld, or if the original is best. Also can't find any high temp earth magnets.
I'd like to get a rotor with a good magnet in it, not sure what would be the best option if MikesXS was too weak.
On a good note I found out that my tail light is what is making my voltage drop so fast.
Now my headlight is out, checked the bulb and it's fine. Turn signals work. Weird cause the bike is charging now.
 

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