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1980 xs650 cutting out half throttle
- Thread starter Jake Violando
- Start date
Jake Violando
XS650 Addict
It happens with my old battery and this brand new one.
Jake Violando
XS650 Addict
It has the same brushes and reg/rec as when it ran great. I cleaned my ground strap off battery. The fuse holders are nice. Ignition switch should be tested?
Yes ohm the ignition switch out or check voltage drop with a load on it
(headlight is fine) or just overhaul it. They are always grotty inside. fuse holders are notorious XS650 weak spots, remove (I suggest replace) all fuses, make sure the fingers grab them snugly. Replace fuses, cause I have found bunches of old fuses that look good but the innards are rotted away. A blade type fuse box replacement is a good and popular upgrade. Often times electircal troubleshooting is just going through and checking repairing one item at a time til the system goes back to working. kill switch overhaul is simple and a good idea also. I just did the kill on "period piece" today.
(headlight is fine) or just overhaul it. They are always grotty inside. fuse holders are notorious XS650 weak spots, remove (I suggest replace) all fuses, make sure the fingers grab them snugly. Replace fuses, cause I have found bunches of old fuses that look good but the innards are rotted away. A blade type fuse box replacement is a good and popular upgrade. Often times electircal troubleshooting is just going through and checking repairing one item at a time til the system goes back to working. kill switch overhaul is simple and a good idea also. I just did the kill on "period piece" today.
Not sure why you would expect the voltage on the outer brush and rotor ring to vary ??
You should just see a static battery voltage on the outer slip ring with the ignition on and the engine not running
if you put your red positive + multimeter prod on the outer brush terminal (brown wire ) and the black multimeter prod directly onto your battery negative terminal with the meter set to DC volts and the ignition switch turned on and engine not running there must be battery voltage showing on your meter.
If you do not see battery voltage on your meter then you need to find out where the live 12v feed to the outer brush is broken or open circuit .
The brown wire which feeds 12v+ to the outer brush and rotor ring comes from your fuse box so check all your fuses are live with the ignition on.
If they are then there is a break in your brown wire between the fuse and the outer brush/rotor ring
If you have 12v+ showing on your meter then move the red positive multimeter prod to the outer copper Rotor ring and test again.
If you still do not see battery voltage on the meter then there is an issue with your brushes or brush holder
You should just see a static battery voltage on the outer slip ring with the ignition on and the engine not running
if you put your red positive + multimeter prod on the outer brush terminal (brown wire ) and the black multimeter prod directly onto your battery negative terminal with the meter set to DC volts and the ignition switch turned on and engine not running there must be battery voltage showing on your meter.
If you do not see battery voltage on your meter then you need to find out where the live 12v feed to the outer brush is broken or open circuit .
The brown wire which feeds 12v+ to the outer brush and rotor ring comes from your fuse box so check all your fuses are live with the ignition on.
If they are then there is a break in your brown wire between the fuse and the outer brush/rotor ring
If you have 12v+ showing on your meter then move the red positive multimeter prod to the outer copper Rotor ring and test again.
If you still do not see battery voltage on the meter then there is an issue with your brushes or brush holder
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Jake Violando
XS650 Addict
Their is 11.6v at idle and 11.8 when it starts to breakup
Before 1/2 throttle. Coming from either brush. With Bike not running and key on, I get no volts at the rotor. Time for brushes??
how exactly are you testing for battery voltage at the rotor ? Please tell me exactly where you measure from with both the multimeter prods. Its important and could give us a clue to what is wrong.
There is absolutely no point in running the engine to check the charging if you do not have battery voltage at the rotor
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Jake Violando
XS650 Addict
I have my positive lead on the outside ring. Like the one picture I posted. And the other on a solid ground. On volts DC. With the brushes in, on the hot one I'm getting 11.2 v not running.with The battery being at 12.5-12.8 when I tested
Jake Violando
XS650 Addict
Btw you're an amazing book of knowledge and such a precise walk through
Ok thats a good answer and tells us several things .
1. that you have a battery voltage at the outer brush and rotor ring and therefore the 12v+ feed to the Rotor is ok
2. that the outer brush is connecting with the outer ring ,so your outer brush is ok.
3. That your frame has a connection with battery negative and is grounded .
Now ....you need to put your multimeter on resistance setting and check that you have continuity (a connection) between the inner copper ring and some point on the frame .The meter will show a 0 ie zero resistance . A reading of 1 will tell you that there is no connection or continuity
If you do get a 0 on the meter ...... then provided the Rotor winding is not open circuit .....the Rotor must be creating a magnetic field .
If you cannot get continuity between the inner Rotor ring and the frame of the bike move your MM black prod to the battery negative terminal, instead of the bikes frame and do the test again.
if you now get a reading then there must be a fault with the inner brush or brush holder, in other words your Rotor inner ring is not getting grounded to complete the circuit ,so your Rotor will not create a magnetic field
ps Apologies for the oversized bold font but it did get your attention.......... right !?
.
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Jake Violando
XS650 Addict
I shall try this and report back. I love the oversized bold. Makes things easy.Ok thats a good answer and tells us several things .
1. that you have a battery voltage at the outer brush and rotor ring and therefore the 12v+ feed to the Rotor is ok
2. that the outer brush is connecting with the outer ring ,so your outer brush is ok.
3. That your frame has a connection with battery negative and is grounded .
Now ....you need to put your multimeter on resistance setting and check that you have continuity (a connection) between the inner copper ring and some point on the frame .The meter will show a 0 ie zero resistance . A reading of 1 will tell you that there is no connection or continuity
If you do get a 0 on the meter ...... then provided the Rotor winding is not open circuit .....the Rotor must be creating a magnetic field .
If you cannot get continuity between the inner Rotor ring and the frame of the bike move your MM black prod to the battery negative terminal, instead of the bikes frame and do the test again.
if you now get a reading then there must be a fault with the inner brush or brush holder, in other words your Rotor inner ring is not getting grounded to complete the circuit ,so your Rotor will not create a magnetic field
ps Apologies for the oversized bold font but it did get your attention.......... right !?
Jake Violando
XS650 Addict
Alright sooo I tested the inner ring via the terminal lug for the brush on the stator. No beeping from my meter, telling me their would be a complete circuit. Weather in on the frame, or the negative terminal on my battery. I'm getting 11.2v ish still DC. If it helps I'm getting 7 ohms on the inner brush, and not 1 ohm on the outer brush. With key off. With key on, 11.6 ohms at inner brush, just OL on outer.
Jake Violando
XS650 Addict
Exeuse me sorry, their is beeping showing continuity
Jake Violando
XS650 Addict
My video of the bike acting up won't upload either
Jake Violando
XS650 Addict
Woah! Progress. I unplugged my regulator rectifier. Tryed to run the bike. So when my fuel valve is on, the carbs leak gas. I forgot to turn it off, so I shut the gas off and tried starting it. Big backfire, actually blew my carb out of the boot. Anyways next kick fired right up and the problem is gone! Rev's to the sky. So I plugged my regulator back in to double check that it's messed up. But is it still revs up perfectly fine? So I'm lost
Jake Violando
XS650 Addict
Went for some test rides. Plugged in, unplugged. Deff the regulator. Thank you very much everyone
so is the battery charging now ? if it isn't the battery is going to go flat pretty soon.
I don't understand what you are saying here Jake . Could you be a little more precise with your choice of words so it makes some sense.
Alright sooo I tested the inner ring via the terminal lug for the brush on the stator. No beeping from my meter, telling me their would be a complete circuit. Weather in on the frame, or the negative terminal on my battery. I'm getting 11.2v ish still DC. If it helps I'm getting 7 ohms on the inner brush, and not 1 ohm on the outer brush. With key off. With key on, 11.6 ohms at inner brush, just OL on outer.
Forget the ohms they are no longer relevant. We know that the rotor is ok.
All we are interested in here is whether or not the inner copper ring on the rotor is getting grounded to the battery negative terminal .
1. Switch the ignition on
2. Do not start the engine.
3. Switch your multimeter to 200ohms which usually has a beep to confirm you have a continuity ie a connection
4. Place the red multimeter prod directly on the inner copper ring of your rotor.
5. Place the black multimeter prod on your negative - terminal of your battery .
Does the multimeter beep or not ?
If it does beep ... keep the red probe on the inner copper ring .......and move the black probe to the green wire fixing bolt on the stator brush holder .
Does it beep now ?
Please let us know what the result is of those 2x tests ......nothing else for the present ok
I don't understand what you are saying here Jake . Could you be a little more precise with your choice of words so it makes some sense.
Alright sooo I tested the inner ring via the terminal lug for the brush on the stator. No beeping from my meter, telling me their would be a complete circuit. Weather in on the frame, or the negative terminal on my battery. I'm getting 11.2v ish still DC. If it helps I'm getting 7 ohms on the inner brush, and not 1 ohm on the outer brush. With key off. With key on, 11.6 ohms at inner brush, just OL on outer.
Forget the ohms they are no longer relevant. We know that the rotor is ok.
All we are interested in here is whether or not the inner copper ring on the rotor is getting grounded to the battery negative terminal .
1. Switch the ignition on
2. Do not start the engine.
3. Switch your multimeter to 200ohms which usually has a beep to confirm you have a continuity ie a connection
4. Place the red multimeter prod directly on the inner copper ring of your rotor.
5. Place the black multimeter prod on your negative - terminal of your battery .
Does the multimeter beep or not ?
If it does beep ... keep the red probe on the inner copper ring .......and move the black probe to the green wire fixing bolt on the stator brush holder .
Does it beep now ?
Please let us know what the result is of those 2x tests ......nothing else for the present ok
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Jake Violando
XS650 Addict
Yes they both beep. It's my regulator rectifier. I tested it. The readings were all similar on the dioeds except one. It was 0.
OK jake but as far as I know you have still not told us if you have a magnet at your rotor have you ?
If there is no magnet at the rotor with the ignition switched on and then it is your rotor that is faulty and no amount of new regulators is going to make your charging system work.
If your multimeter says you have 12v+ going into the rotor (outer copper ring) and the other end of the rotor coil ( inner copper ring) is grounded ,then your rotor must be creating a magnetic field. its impossible for it not to be so what are you doing wrong ?
Have you put your multimeter negative lead on the the rotor locking nut (ground) and then the positive lead to each of the rotor copper rings in turn and verified that neither of the copper rings is shorted out to ground ? in other words on both those tests you shouldn't hear a beep.
jeez......
If there is no magnet at the rotor with the ignition switched on and then it is your rotor that is faulty and no amount of new regulators is going to make your charging system work.
If your multimeter says you have 12v+ going into the rotor (outer copper ring) and the other end of the rotor coil ( inner copper ring) is grounded ,then your rotor must be creating a magnetic field. its impossible for it not to be so what are you doing wrong ?
Have you put your multimeter negative lead on the the rotor locking nut (ground) and then the positive lead to each of the rotor copper rings in turn and verified that neither of the copper rings is shorted out to ground ? in other words on both those tests you shouldn't hear a beep.
jeez......
Jake Violando
XS650 Addict
I'll check after work today. Sorry for my low knowledge. Trying to learn. Only way I learn is by doing it
