Running rough - now won't start
#21
04-02-2009, 06:51 AM
Here's a good way to bench test your generator. Note that [in my limited experience] this is not a conclusive test that the gen is good. Don't try this with the generator on the bike:
[i]. connect a jumper from the "+" battery post to the "A" armature terminal on the gen.
[ii]. Connect a jumper from the "-" battery post to the "F" field terminal of the gen.
[iii]. Now take a third jumper from the "-" battery post and touch it to the case of the gen.
If all is well the generator will run like an electric motor. With the gen gear pointing away from you the rotation is clockwise.
From the 79 to 85 FM:
1. Generator Test #1: Residual Magnetism
Disconnect both the A and F terminal wires. Connect the +ve voltmeter lead to the A and the -ve lead to ground. Run the engine at about 2000 RPM. The meter should read at least 2.0 volts. If the voltage is low polarize the generator and repeat the test. If the generator fails this test it must be disassembled for repair.
2. Generator Test #2: Maximum Output
Remove both the A and F terminal wires. Connect the +ve voltmeter lead to the A and the -ve lead to ground. Run the engine at about 2000 RPM. MOMENTARILY [not longer than 10 seconds] connect a jumper lead from ground to F and read the meter. The meter should read 25 to 30 volts DC. If the generator fails this test it must be disassembled for repair.
3. Polarizing the Generator
With the generator fully installed in the bike, all connections made, ignition off; connect one end of a jumper wire to the gen A, and momentarily touch the other end to the battery +ve terminal.
Usually [but not always they say], you will get a spark at the battery terminal and a light clunk sound from the gen. In my limited experiencxe if you do not get the spark and the clunk then something is wrong.
[i]. connect a jumper from the "+" battery post to the "A" armature terminal on the gen.
[ii]. Connect a jumper from the "-" battery post to the "F" field terminal of the gen.
[iii]. Now take a third jumper from the "-" battery post and touch it to the case of the gen.
If all is well the generator will run like an electric motor. With the gen gear pointing away from you the rotation is clockwise.
From the 79 to 85 FM:
1. Generator Test #1: Residual Magnetism
Disconnect both the A and F terminal wires. Connect the +ve voltmeter lead to the A and the -ve lead to ground. Run the engine at about 2000 RPM. The meter should read at least 2.0 volts. If the voltage is low polarize the generator and repeat the test. If the generator fails this test it must be disassembled for repair.
2. Generator Test #2: Maximum Output
Remove both the A and F terminal wires. Connect the +ve voltmeter lead to the A and the -ve lead to ground. Run the engine at about 2000 RPM. MOMENTARILY [not longer than 10 seconds] connect a jumper lead from ground to F and read the meter. The meter should read 25 to 30 volts DC. If the generator fails this test it must be disassembled for repair.
3. Polarizing the Generator
With the generator fully installed in the bike, all connections made, ignition off; connect one end of a jumper wire to the gen A, and momentarily touch the other end to the battery +ve terminal.
Usually [but not always they say], you will get a spark at the battery terminal and a light clunk sound from the gen. In my limited experiencxe if you do not get the spark and the clunk then something is wrong.
Last edited by IronMick; 04-02-2009 at 06:55 AM.
#22
04-02-2009, 07:59 AM
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Here is the way you test the generator output.
It requires you to have a zero to 30 amp ammeter, so you most likely do not have one.
Go to the parts house and get a small 0-30 under the dash type ammeter, like you will find on an under the dash mount oil. water and temp gauges. You only want the ammeter. Costs you perhaps $10 at most.
Then follow the instruction below. If the generator is bad this test will tell you. If the generator output is good, then the problem is with the voltage regulator. If not good, then it is time to remove the generator and start that repair........... pg
And then when you are done, if the generator is good be sure to flash the fields before starting the bike again. Done like so......
It requires you to have a zero to 30 amp ammeter, so you most likely do not have one.
Go to the parts house and get a small 0-30 under the dash type ammeter, like you will find on an under the dash mount oil. water and temp gauges. You only want the ammeter. Costs you perhaps $10 at most.
Then follow the instruction below. If the generator is bad this test will tell you. If the generator output is good, then the problem is with the voltage regulator. If not good, then it is time to remove the generator and start that repair........... pg
And then when you are done, if the generator is good be sure to flash the fields before starting the bike again. Done like so......
#23
04-02-2009, 08:08 AM
#24
04-02-2009, 08:52 AM
Outstanding HDF Member
Yes, what you need to use for 'the short jumper wire to ground' is a 16ga wire, not battery or 'jumper' size cable.
All wiring is basically going to be 16 ga.
The exception is when you are talking about the main starting circuit which is from the battery post(s)............. negative to ground..... and from positive to the starter solenoid.
These two wires (cables actually) carry a lot of current and that is why they are large cables instead of light gage wire.
If you were to use 16ga wire in place of the heavy cables (DON"T DO THIS) the demand from the starter motor for current will quickly overheat the light 16ga wire and catch fire.
That is the reason you had so much trouble when hooking up your truck battery in the video.
The wire size you were using was far too light and the wire could not carry the current needed to turn over the starter motor.
Thus the reason battery cables are so large compared to all the other wiring on the bike (or automobile)
pg
All wiring is basically going to be 16 ga.
The exception is when you are talking about the main starting circuit which is from the battery post(s)............. negative to ground..... and from positive to the starter solenoid.
These two wires (cables actually) carry a lot of current and that is why they are large cables instead of light gage wire.
If you were to use 16ga wire in place of the heavy cables (DON"T DO THIS) the demand from the starter motor for current will quickly overheat the light 16ga wire and catch fire.
That is the reason you had so much trouble when hooking up your truck battery in the video.
The wire size you were using was far too light and the wire could not carry the current needed to turn over the starter motor.
Thus the reason battery cables are so large compared to all the other wiring on the bike (or automobile)
pg
#25
04-02-2009, 09:49 AM
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Yes, what you need to use for 'the short jumper wire to ground' is a 16ga wire, not battery or 'jumper' size cable.
All wiring is basically going to be 16 ga.
The exception is when you are talking about the main starting circuit which is from the battery post(s)............. negative to ground..... and from positive to the starter solenoid.
These two wires (cables actually) carry a lot of current and that is why they are large cables instead of light gage wire.
If you were to use 16ga wire in place of the heavy cables (DON"T DO THIS) the demand from the starter motor for current will quickly overheat the light 16ga wire and catch fire.
That is the reason you had so much trouble when hooking up your truck battery in the video.
The wire size you were using was far too light and the wire could not carry the current needed to turn over the starter motor.
Thus the reason battery cables are so large compared to all the other wiring on the bike (or automobile)
pg
All wiring is basically going to be 16 ga.
The exception is when you are talking about the main starting circuit which is from the battery post(s)............. negative to ground..... and from positive to the starter solenoid.
These two wires (cables actually) carry a lot of current and that is why they are large cables instead of light gage wire.
If you were to use 16ga wire in place of the heavy cables (DON"T DO THIS) the demand from the starter motor for current will quickly overheat the light 16ga wire and catch fire.
That is the reason you had so much trouble when hooking up your truck battery in the video.
The wire size you were using was far too light and the wire could not carry the current needed to turn over the starter motor.
Thus the reason battery cables are so large compared to all the other wiring on the bike (or automobile)
pg
Ok, so you are agreeing that my little jumper cables will work to flash the generator? I'm sorry for all the questions, I just want to get this figured out and get her running again.
#26
04-02-2009, 10:07 AM
#27
04-02-2009, 11:36 AM
Outstanding HDF Member
Ok, so you are agreeing that my little jumper cables will work to flash the generator? I'm sorry for all the questions, I just want to get this figured out and get her running again.
Yes, absolutely. The small jumper wires will be fine.
When you said jumper earlier I thought you were talking about real jumper cables, not the light wires you originally used for jumper cables...... pg.
Yes, absolutely. The small jumper wires will be fine.
When you said jumper earlier I thought you were talking about real jumper cables, not the light wires you originally used for jumper cables...... pg.
#28
04-02-2009, 11:54 AM
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Ok, so you are agreeing that my little jumper cables will work to flash the generator? I'm sorry for all the questions, I just want to get this figured out and get her running again.
Yes, absolutely. The small jumper wires will be fine.
When you said jumper earlier I thought you were talking about real jumper cables, not the light wires you originally used for jumper cables...... pg.
Yes, absolutely. The small jumper wires will be fine.
When you said jumper earlier I thought you were talking about real jumper cables, not the light wires you originally used for jumper cables...... pg.
#29
04-02-2009, 12:21 PM
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#30
04-02-2009, 12:53 PM
Outstanding HDF Member
Ok, the other thing is I do have a multimeter. It does read amps. So will that suffice to read the amps coming out of the generator or do I need that other one you were talking of? I don't see why not. No?
Your multimeter reads amps? Then it must be a multimeter with a clamp claw. This measures amps on an AC circuit. We are dealing with a DC circuit here. So no, this will not work.
A meter that will read DC amps cost about $600, so I am sure you do not have one of those.
Here is what you need to get at an auto parts store. These are used on tractors and can be used on cars as well......... pg
Your multimeter reads amps? Then it must be a multimeter with a clamp claw. This measures amps on an AC circuit. We are dealing with a DC circuit here. So no, this will not work.
A meter that will read DC amps cost about $600, so I am sure you do not have one of those.
Here is what you need to get at an auto parts store. These are used on tractors and can be used on cars as well......... pg