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Discussion Starter #1
As some of you know, I’m restoring a 2000 Monster 750. It has only 8300 miles and had been sitting outside for many years. I’ve replaced almost everything that needed replacing and have cleaned and restored every nut and bolt. The engine is very clean and it absolutely looks to be a low mileage bike.

I’ve reinstalled the wiring harness and now is when the fun/frustration beings.

I’ve got the lights, blinkers and taillight/brakes light all working. I have a brand new battery but when I hit the start button...nothing...not even a click. I’ve tried it with the kickstand up and down and it’s in neutral. Tried it with the clutch lever in and out. Nothing.

I’ve tested the relays and they click when I add juice. I have a power probe so I can add power to anything.

When I touch the power probe to the starter directly, it turns the engine over very slowly then triggers the circuit breaker on the power probe. I’m thinking that the current is just too strong on the starter which is why it threw the breaker.

I know the starter turns which is a good thing. The relay tests fine. The only other things I can think of is the solenoid or the start switch.

Any other thoughts?
 

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Well I misread your question.

Put bike in neutral and "add juice" to the selenoid bobbins, does the starter turn?

Follow circuit of starter button, should be easy to diagnose.
 

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So I have a 1999 M750
Mine does not have the clutchswitch or kickstand interlock
So when the kick/side stand is down all that little switch down there does is illuminate a warning/idiot light on the dash
There is also no clutch switch
So make sure you are in neutral or pull the clutch in anyway
mine will jump forward with the start button if it was left in gear when parked
Please correct me good forum members if his 2000 M750 is not the same, I don't know if this is the case.
On a project build (efi Triumph Hinkley Triple) the interlocks gave me fits until I got everything sorted.....Bike would not start
So hopefully you can rule those 2 things out in trouble shooting your M750.
 

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Discussion Starter #5
So I have a 1999 M750
Mine does not have the clutchswitch or kickstand interlock
So when the kick/side stand is down all that little switch down there does is illuminate a warning/idiot light on the dash
There is also no clutch switch
So make sure you are in neutral or pull the clutch in anyway
mine will jump forward with the start button if it was left in gear when parked
Please correct me good forum members if his 2000 M750 is not the same, I don't know if this is the case.
On a project build (efi Triumph Hinkley Triple) the interlocks gave me fits until I got everything sorted.....Bike would not start
So hopefully you can rule those 2 things out in trouble shooting your M750.
Thanks. This is a process of elimination so I can check those off. For some reason I’m not getting a kickstand down light?
 

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2001 900SSie
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Is the pump priming at key on and the stop/run switch in the run position?
If no then the "ignition"relay coil is not not getting power, connected to battery negative by the ECU.
The words and diagram attached are for a 900SSie but the principles are the same when you compare the attached diagram to the Monster.
I have also attached the ECU pins for the A8 and A0 ECUs.
 

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it's a carby monster.

one day, when we can teleport, they'll be a few of us standing next to you telling you what you've done wrong.

for now, i really think you need to get a professional who specifically knows these bikes, to go over it and fix what you've messed up. if you missed plugging in one of the voltage reg connectors, i think you're out of your depth here.
 

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2001 900SSie
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Oops - assumed it was EFI, as in ie in Ducati terminology.
The attachment is what voltages you should see at various user inputs/actions.
Turning over slowly makes me think you have a shit connection between the battery and the starter motor.
Could be in the positive or negative.
With a multimeter set on resistance scale you can test resistance between battery plus and the solenoid to see if that is crap.
Same with engine to battery negative to the engine.
Just a process of elimination.
As Belter wrote, maybe time to take it to someone who knows what to look for or not ride this northern hemisphere summer.
 

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2000 M900Sie, 2003 Aprilia RSV Mille-R, 2x 1981Guzzi Monzas, IWL Pity, Piaggio Hexagon, PX Vespa
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Pull the plug from the back of the starter solenoid.
Stick the prongs from you multimeter in there with it set to 20V.
Key on.
Hit the start button.
If you get Battery Voltage (12v+) you starter solenoid is dead. I had this happen to me whilst on Holiday in Italy and in an emergency started the bike by bridging the two large terminals on the starter solenoid with my door keys. I do not advise this. But it got me out of trouble.

If you dont get Battery Voltage, either:
the big wire that doesn't go to the starter low down on the engine isnt live. You did check this right?

The starter button is broken (unlikely) or isnt getting 12V - test the connector to that switch with the key on.
No 12V at the connector then chase it back to the relay.

As others have suggested, taking it to a specialist/someone who knows what they are doing may well be the quickest way forward.
 

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Discussion Starter #10 (Edited)
I appreciate everyone’s suggestions. This is a project bike and one that I want to learn on. I don’t need it on the road anytime soon. I have a new XDiavel for that. I wanted it to restore and learn on. I labeled every connector when I removed the harness so I know that every connector is back where it came from. There is one wire that appears to be a ground that I’m still determining, but I’m sure it’s a ground. It wasn’t attached to anything when I took it apart.

This is 50 year old technology, no ECU or EFI. I should by process of elimination, be able to figure this out. My bet is a bad solenoid. This bike had been sitting outside for maybe 10 years.

I picked it up for $500 but unfortunately, I’ve dumped more money into it than I care to admit.

If I can’t figure this out then yes, I’ll take it to a shop, but it seems so basic.

This bike was a real mess when I got it and I took it down to the frame. It’s all back together and now it’s about getting it started.

Here’s the bare frame eaten away by battery acid and today. It looks great, but I need to get it to run. It’s been a labor of love and learning and something to keep my mind off of Covid these past few months.

This is fun for me...





 

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Discussion Starter #11 (Edited)
Process of elimination right?

So I jumped the starter with jumper cables and the starter works fine.

I put a test light on the positive side of the solenoid and it’s getting direct juice from the battery. I put the light on the side that goes to the starter and it gets power when I turn the key on. So basically I can turn the key on and off and the light goes on and off.

No clicking noises, just power to the other side.

The lead to the starter is live also.

Does this tell me that the solenoid is good? I’m not sure. It tells me that I’m completing a circuit when the key is on but it’s not engaging the starter which it shouldn’t until the start button is pushed.

So...either the solenoid is bad, or the switch is bad. It’s not the battery (new) and it’s not the starter. I also tested the relays by adding power to them and they so I can “assume” those are good as well.

I guess my next test is to take the start switch plug off of the back of the solenoid and test the switch. If I’m getting juice when the switch is pushed, I have to assume that the solenoid is toast.

All make sense?

I had to walk away for a few so I took my XD out for a quick spin.
 

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Discussion Starter #12
Ok, I think it’s the solenoid.

I pulled the switch connector off of the back of the solenoid and put a light tester in it.

One side has power and the other no power. When you push the start button, the side with no power lights the light; meaning power.

Battery ok
Starter ok
Switch ok
Relay clicks, not sure if that’s ok or not but it engages.
Solenoid gets juice on the starter side when the key is on but doesn’t engage the starter.

So, I have to conclude that it’s the solenoid right?

Could it be a faulty ground somewhere?
 

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Discussion Starter #13
So I put everything back together. Made sure the grounds were tight. Put the kickstand up and pulled in the clutch just to be safe.

Pushed the start button...nothing.

I think it’s the solenoid.

Does anyone think any differently?
 

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2001 900SSie
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I am a bit confused about your post #12 and the results.
As Chris wrote, you need to pull off the connector that goes to the solenoid coil.
With this off place the probes of the test light into this connector.
Press the start button and it should light.
If it lights, then the issue is with the solenoid.
If it does not light, then an issue with the wiring.
Honestly you really need a multimeter to test electrics, even the cheapest one from a discount store or wherever.
Put one probe in the connector that has the red/black wire. Connect the other probe to battery negative.
Press the switch
No light - then the issue is in the wiring or start switch.
Lights - then an issue with the other wire that goes to battery negative.
To test this, connect one probe of the light to battery positive.
Connect the other to the not red/black wire in the connector.
if it lights, then that wire I OK.
If it does not light then there is a problem in that wire or a connection back to battery negative.

You can also test the solenoid carefully using wires.
With the connector still off.
Find the solenoid coil terminal that corresponds to red/black. Connect that to battery positive.
Connect the other solenoid coil terminal to battery negative and it should click to signify it is OK.
No click = not OK.

Another thing you can do is gently take the solenoid with a rubber mallet a few times.
It may be stuck having been in the weather for a long time.

The diagram Iposted in #8 is the same, so if chasing voltages, use that.
 

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Discussion Starter #16 (Edited)
I am a bit confused about your post #12 and the results.
As Chris wrote, you need to pull off the connector that goes to the solenoid coil.
With this off place the probes of the test light into this connector.
Press the start button and it should light.
If it lights, then the issue is with the solenoid.
If it does not light, then an issue with the wiring.
Honestly you really need a multimeter to test electrics, even the cheapest one from a discount store or wherever.
Put one probe in the connector that has the red/black wire. Connect the other probe to battery negative.
Press the switch
No light - then the issue is in the wiring or start switch.
Lights - then an issue with the other wire that goes to battery negative.
To test this, connect one probe of the light to battery positive.
Connect the other to the not red/black wire in the connector.
if it lights, then that wire I OK.
If it does not light then there is a problem in that wire or a connection back to battery negative.

You can also test the solenoid carefully using wires.
With the connector still off.
Find the solenoid coil terminal that corresponds to red/black. Connect that to battery positive.
Connect the other solenoid coil terminal to battery negative and it should click to signify it is OK.
No click = not OK.

Another thing you can do is gently take the solenoid with a rubber mallet a few times.
It may be stuck having been in the weather for a long time.

The diagram Iposted in #8 is the same, so if chasing voltages, use that.
Hi Punch,

What you describe is what I did. I pulled the connector out of the back of the solenoid and put a probe into it. I have the power probe which is a multi meter and it can power things up.

The switch on the handlebar is fine. It lights the probe when pushed. I’ve tested everything and the only thing I didn’t do is hit the solenoid with a rubber mallet.

For some reason I can’t get your attachments to open. I use an iPad so I don’t think I have adobe if that’s the format of your diagrams.

For 50 bucks, even if the solenoid is good, it’s piece of mind having a brand new one.
 

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PNG attached
Not sure what a power probe is, but I would be using the mm on the 20V DC range.
You could also measure the resistance of the solenoid coil.
900SS off run start voltages.png
 

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Discussion Starter #18
Thanks. A power probe is a multi meter that has a switch on it and allows you to power something up if you choose. If you want to test a horn for example, you can put the negative clip on one side and the probe on the other, then push the button and you can power up the horn and see if it works. You can use this for all sorts of things. I just used it to make sure my lights were working before I installed them on the bike.
 

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2001 900SSie
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You don't need to understand the diagram as you have determined you have power to the solenoid coil.
All you need to determine is - is the solenoid stuffed?
AS you have a new oncoming I guess you will find out.
 
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