What do you think Causes Startus Interuptus?

[Kiwi_Roy]

I waited a while to see if any other ideas came out of the woodwork. I was surprised how the poll came out 30 - 50 Amps that's about right, the more current you put thru the coils the more chance of it starting

My educated swag is 40+ amps.  The lie to this answer is that the solenoid is an inductive device and the intrush current at activation will be huge.

No. it's the other way around, the inductive reactance resists change, your curve is almost correct though, the spike is caused by putting 12 Volts across a 0.25 Ohm coil

[Kiwi_Roy]

The big current is the pull-in winding.  The hold-in doesn't need nearly so much.  So the surge through the switch or relay is probably in the 30-40-amp range with everything fresh, and could push 50amp as 'lectrical and mechanical resistance increase over time.  But that's just the pull-in, and it happens between the Ka- and the -thunk of starter engagement.  Hold-in power is minor.  It happens starting with -thunk and stopping when you release the button.

RDK pretty much nailed it  Ka (45-50Amps)-- thunk (10 Amps)

[Kiwi_Roy]

  it may not quit get to 20 amps of inrush with the factory wiring. But a direct wire may exceed 40.
And the resistance alone the way is everything. Connectors, small wires, and the wimpy 15 amp fuse even.
So I'll vote 30 to 40, but that could be skewed to be a different number.

20 Amps to 40 Amps eh,
 Since the strength of a magnetic field is proportional to Ampere turns, that's double with a direct feed

[Kiwi_Roy]

  My fix has been to feed that relay contact directly from the 30 amp fused circuit. Basically: 30 amp fuse, relay contact, wiring to solenoid.

OMG has it figured out

[Kiwi_Roy]

I added "the fix" of the circuit that bypasses the starter switch to go right to the relay.  I saw a bump of 0.5 volt, max, to the solenoid, and decided it wasn't worth the complication.

It's possible that the switches on my '09 V7 hadn't yet degraded.  Perhaps when they age more the fix will be useful.

I think if you were to monitor the Voltage difference at the moment of first closing with the high current coil in circuit you would find the difference to be Volts rather than fractions.

[Kiwi_Roy]

Kev M and Beetle are on top of it.

Charlie B knows how to fix it

I have seen the solenoids gummed up also, oil goes like chewing gum, I use a couple of drops of 3 in 1

[Kiwi_Roy]

To summarise.
I don't think any Guzzi is immune to Startus Interoptus.
A direct feed to the Start Relay will lessen the chance of it occurring

I have measured the solenoid current on several bikes, with direct wiring the least I got was 37 Amps.

If anyone is interested in a Startus Interuptus fix for their bike send me a PM
Include, bike year and model with an e-mail address so I can send sketches, converse directly.
Cheers
Roy

[beetle]

Kev M and Beetle are on top of it.

I may have exaggerated the actual length of the wiring.

[sign216]

I think if you were to monitor the Voltage difference at the moment of first closing with the high current coil in circuit you would find the difference to be Volts rather than fractions.

Could be, could be.  As it is there's no problem, so I'm not going to "fix it until it's broken."

[donn]

There is something else that changes between one start and the next, the circuit resistance, in particular the ignition switch, as the contacts get dirty no two closings result in the same resistance. It may only vary by a fraction of an Ohm but that's all it takes when you are trying to switch 40+ Amps, do the Math
Current/Resistance = Voltage drop

If anyone here actually experiences this problem, is there anything you can say about when it happens, and when it's likely to be over and the starter works again?

I guess if everyone's went like mine, with what might be a 20 minute outage depending on various factors like how hot the motor is and how cold the air, you all wouldn't be going on like this.  So what does it look like with your Guzzis?  Starts again after some random number of button presses, might be the second hit or the 200th?  Starts the next day?  Only starts before noon?  Never starts again until you rewire it?

[Mr Revhead]

I've been following this with interest as my 03 EV has a starting issue which I thought was this, but now I'm not so sure.
I don't get the "relay click and nothing"  I get starter engagement and a half hearted "Rrr" and stop. Then I release the starter button and immediately hit it again and 99.9% of the time it cranks and starts properly.
 
My battery is fine, tested at 12.75v after sitting since Sunday. Previous owner has said it's done it since new, it's done 53K

Is this "Startus Interuptus" or do I have another issue?

[Kiwi_Roy]

I've been following this with interest as my 03 EV has a starting issue which I thought was this, but now I'm not so sure.
I don't get the "relay click and nothing"  I get starter engagement and a half hearted "Rrr" and stop. Then I release the starter button and immediately hit it again and 99.9% of the time it cranks and starts properly.
 
My battery is fine, tested at 12.75v after sitting since Sunday. Previous owner has said it's done it since new, it's done 53K

Is this "Startus Interuptus" or do I have another issue?

That seems like another issue, clean your battery terminals and check where the ground connects to the chassis or engine.
Test the battery Voltage while you are trying to start i.e. while it is under load, it shouldn't drop below 11

[charlie b]

The first was the 'normal' startus interruptus.  The fix to the relay wiring noted above.

That worked well, but, I had installed a generic 30A automotive relay.  It worked fine for a while, then the problem would come back.  I finally got a "starter relay" from NAPA and that has worked well.

When this has happened to me, sometimes repeated stabs at the starter button would make it work.  But, this deteriorated over time.  At first it was one or two.  Then 5 or 6.  Then nothing.  The symptom is just a click of the small relay, not the solenoid.  This is easily tested.  Just carry a jumper wire (or insulated handle screwdriver) and 'hotwire' the solenoid.  Be very careful you don't short to ground and make SURE the bike is in neutral.

[Wayne Orwig]

I've been following this with interest as my 03 EV has a starting issue which I thought was this, but now I'm not so sure.
I don't get the "relay click and nothing"  I get starter engagement and a half hearted "Rrr" and stop. Then I release the starter button and immediately hit it again and 99.9% of the time it cranks and starts properly.
 
My battery is fine, tested at 12.75v after sitting since Sunday. Previous owner has said it's done it since new, it's done 53K

Is this "Startus Interuptus" or do I have another issue?

You imply that the solenoid pulled in. You don't have 'startup interruptus'.
You may have magnets loose inside the starter. Pull the starter and have it cleaned up and inspected inside.

[Wayne Orwig]

If anyone here actually experiences this problem, is there anything you can say about when it happens, and when it's likely to be over and the starter works again?

I guess if everyone's went like mine, with what might be a 20 minute outage depending on various factors like how hot the motor is and how cold the air, you all wouldn't be going on like this.  So what does it look like with your Guzzis?  Starts again after some random number of button presses, might be the second hit or the 200th?  Starts the next day?  Only starts before noon?  Never starts again until you rewire it?

If it happens, turn the ignition switch on and of and on and off a few times. The contacts may wipe clean and get better, maybe.
If your design has the 15 amp fuse in line with the solenoid, bump it to a 20 amp. The sky will not fall when you do that, do it.
If that doesn't help, find a hill to bump start it. Or try a jump start, as a bit of extra voltage may do the trick.
If you are just worried about it, put in the direct wire fix and move on.

[acogoff]

     My personal starting problem is caused by old age and a benign swelling of the prostate. The Guzzi's problem is usually corrosion somewhere and or Trolls.

[donn]

If you are just worried about it, put in the direct wire fix and move on.

I have put in the direct wire.  It's more of a band-aid than a fix, but it helped a lot.

[Kiwi_Roy]

If anyone here actually experiences this problem, is there anything you can say about when it happens, and when it's likely to be over and the starter works again?

I guess if everyone's went like mine, with what might be a 20 minute outage depending on various factors like how hot the motor is and how cold the air, you all wouldn't be going on like this.  So what does it look like with your Guzzis?  Starts again after some random number of button presses, might be the second hit or the 200th?  Starts the next day?  Only starts before noon?  Never starts again until you rewire it?

If you continue to experience lack of starting why not fix it?
Measure the Voltage at the solenoid trigger terminal while pushing the button, should be ~ 12 Volts

Find out where it's being lost. On most bikes it's thru the ignition switch,
Clean the switch or provide a more reliable source of 12 Volts to the 30 terminal of the relay
Check all the other connections are clean tight and greased like the spade at the solenoid

If you don't have a schematic look for one close on this site.
http://www.thisoldtractor.com/guzzi007/sportissimo.html

[not-fishing]

Don't know, don't care.  Someone else came up with a fix and I installed it.  It's a Boy Scout thing and Electric's is Hard

[donn]

If you continue to experience lack of starting why not fix it?
Measure the Voltage at the solenoid trigger terminal while pushing the button, should be ~ 12 Volts

You're talking about band-aids.  I've done the band-aid thing, and it works pretty well, just as one would expect not 100%.  Since as best as I can tell the problem when it happens is a bad ground, I've idly thought about connecting a ground wire across the starter/motor joint where I think the ground fails.  But it's one of those things, the problem is quite infrequent, and even if we could measure motivation with a multitester you could barely detect mine.

[atavar]

I've idly thought about connecting a ground wire across the starter/motor joint where I think the ground fails.  But it's one of those things, the problem is quite infrequent, and even if we could measure motivation with a multitester you could barely detect mine.

If you wanted to experiment go ahead and make your jumper and put a ten amp fuse in the middle of it.  If the fuse blows you will know current is travelling through the jumper.

[LaMojo]

If you really want to upgrade to a more robust starter circuit, wire one of these babies in.  Yes I know, it's probably an overkill but as a bonus it can be additionally wired to a remote secret starter button to energize the starter motor, bypassing the bar mounted switch and the cube relay.

[Mr Revhead]

Thanks Roy and OMG, I'll follow your suggestions and start another thread if needed. 

[charlie b]

You're talking about band-aids.  I've done the band-aid thing, and it works pretty well, just as one would expect not 100%.  Since as best as I can tell the problem when it happens is a bad ground, I've idly thought about connecting a ground wire across the starter/motor joint where I think the ground fails.  But it's one of those things, the problem is quite infrequent, and even if we could measure motivation with a multitester you could barely detect mine.

If you want to wire a separate ground it is simple to do.  Get a good cable and wire it from the ground terminal on the solenoid and bolt the other end to the same place the neg cable from the battery bolts to the frame.  On my bike it is about 6inches away from the solenoid.

PS I consider how the factory wired the starter relay to be a "band aid".  Rewiring it was the proper way to make it work.

[Wayne Orwig]

You're talking about band-aids.  I've done the band-aid thing, and it works pretty well, just as one would expect not 100%.

What equipment and what methods did you use to indicate it is a band aid.
I used a Fluke ScopeMeter and current shunts to measure the voltage and current at various points. I found all of the voltage drops in the system and fixed the problem.

It sounds like you have a different or additional issue from the typical startus interuptus.

[donn]

It sounds like you have a different or additional issue from the typical startus interuptus.

That's why I asked those questions, about what happens in the typical case.  charlie b described his scenario, and indeed it was different from mine - but who knows if his is typical?

[Sasquatch Jim]

  Well considering that the solenoid is nothing more than a relay.  Because it draws so much current, it often is energized by a a smaller relay.  The whole point is to have a small petite handlebar switch that can't handle much more than an amp of power start your engine.
 Now being an old geezer means that I remember cars that didn't have a solenoid in the starter system at all.
  Down on the floor board in a corner was a heavy duty plunger like button with a strong return spring.  To start the engine, you turned on the key and stepped on this plunger hard.  The plunger was a really heavy duty switch that sent power to the starter motor which spun the engine to start.  Since most of these old vehicles were six volt systems, the amperage to start was ferociously high.  Modern twelve volt systems
require much less starting amps.  Why not equip your motorcycle with a big manual starting switch like those old cars had?  Modern motorcycle engines require a lot less amps than those old six volt cars so the switch need not be a physically massive to do the job.  An additional plus is that a solenoid requires a substantial power draw just to close.  This is just that much power not available to spin the starter motor.
 Therefore a manual switch should be far more dependable than any system using relay and solenoid circuits.
 Sometimes luddite tech can have advantages.

[Kiwi_Roy]

You're talking about band-aids.  I've done the band-aid thing, and it works pretty well, just as one would expect not 100%.  Since as best as I can tell the problem when it happens is a bad ground, I've idly thought about connecting a ground wire across the starter/motor joint where I think the ground fails.  But it's one of those things, the problem is quite infrequent, and even if we could measure motivation with a multitester you could barely detect mine.

A band aid? is that a temporary fix until the factory comes up with a permanent one, how long do we have to wait for that?
The factory screwed up, have you seen any evidence that they tried to fix it
What OMG and I propose is a permanent fix, a re-design if you will, wire the start circuit in accordance with good electrical practice.

Feeding the Start relay contact direct from the battery with a dedicated fuse or at least from a circuit not run through the Ignition switch
Adding a main fuse to protect the unfused wiring to and from the ignition switch (the newer bikes have this)

[charlie b]

donn,

Sorry but I didn't see what your starting problem is.  You mention the environmental conditions, but, what does the bike do?

Do you get just a click from the starter relay or do you get a clunk from the solenoid?  If it is just a click from the relay, then try changing relays first (since you say yours is direct wired).  Until I bought a relay specifically for starting I had them fail on a regular basis.  And, yes, heat was the first indication, like after a gas stop.  On mine the relay was located next to the rectifier, which is not a very cold place to be (I have since relocated it to the other side of the bike).

FWIW, I had a bad solenoid at one time as well.  I figured my 30yr old one was about to go so I installed a new one.  Well, at first only when hot, later at just about any time, it would just clunk.  Turns out it was not engaging the starter contacts correctly.  The clunk was the pinion hitting the ring gear, but, not meshing.  If I put the bike in gear, rocked it a little, put it back in neutral, then it would start.

Or, your solenoid contacts might be bad and you need a new one.  Or it is 'stuck' or 'gummy' and needs to be cleaned.

Several reasons why a solenoid won't operate correctly.

[donn]

Sorry but I didn't see what your starting problem is.  You mention the environmental conditions, but, what does the bike do?

Do you get just a click from the starter relay or do you get a clunk from the solenoid?  If it is just a click from the relay, then try changing relays first (since you say yours is direct wired).  Until I bought a relay specifically for starting I had them fail on a regular basis.  And, yes, heat was the first indication, like after a gas stop.  On mine the relay was located next to the rectifier, which is not a very cold place to be (I have since relocated it to the other side of the bike).

Ah, maybe yours was not so different from mine.  Gas stop, "rest" stop, after enough miles to get the motor good and hot.

Then the click with no clunk or anything, the symptoms we know, and the "fix" to increase the voltage does dramatically reduce the incidence of the problem.

But the circumstances point to the real cause of the problem.  Sure, the switch circuit has kind of low voltage.  But day after day it works fine, in all kinds of weather, with the battery run down so low it will barely turn over, continues to work fine.  Then one day you get it real hot, cool it down for a few minutes, and click.  OK!  The source of the problem wasn't the voltage, was it?

You said before that in one or more cases it took some random number of attempts, which is different.  I mean if it really lasts some random amount of time, maybe seconds / maybe days - then the switch contacts and other ideas suggested above start to sound more likely.

I like the manual switch idea!  I may have Luddite tendencies myself.