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Kiwi_Roy last won the day on November 26 2021

Kiwi_Roy had the most liked content!

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  • My bikes
    VII Sport & Griso long gone72 Eldorado, V7iii Special 76 Convert aka Magic Carpet Ride
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    Penitentiary New Westminster BC

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  1. As soon as the solenoid closes the main contact the Grunt coil is effectively switched out of circuit so all you will see is the holding coil current, It should be higher. Typical holding coil resistance is 1.25 Ohms, (12 Volts / 1.25 Ohms = 9.6 Amps) Assuming you are measuring the current with the starter working hard, it's pulling 150 - 200 Amps pulling the battery Voltage down below 9 Volts, perhaps even as low as 6. If you measure the Voltage across the coil that will back up your current readings. e.g. (9 Volts / 1.25 Ohms = 7.2 Amps) (6 Volts / 1.25 Ohms = 4.8 Amps) Note: While the solenoid is engaging the gear the load on the battery is quite light (<60 Amps) so the Voltage will be almost 12 Volts, its only once the gear is in place the main contact switches power to the motor the load goes over 100 Amps. It takes the solenoid 15 - 50 milliseconds to engage the gear and close the main contact.
  2. Hi Guzziart, I wasn't able to find the wiring diagram on the Electrosport website but I see the ESR531 is a 3 wire regulator whereas the ESG814 is a single phase (2 wire) Stator, If it's working ok, don't worry about it. Your headlight relays are an improvement over the old system, don't change back not only does it eliminate the flakey Voltage reference, i'm sure you notice the headlight is brighter. I don't believe the Electrosport regulator needs grounding, the old Ducati Energia did because there was no wire connecting to battery Negative. The regulator is now sensing the Voltage directly from the battery Technical Article Figure 1 OR from the ignition switch Technical Article Figure 2 I would be more than happy with the battery Voltage you are seeing.
  3. Guzziart, Please post the make and model of your new regulator along with any changes you might have made to the wiring. Have you made any changes to the headlight wiring e.g. a pair of relays fed directly from the battery. The original Voltage reference downstream of the headlight relay is flaky
  4. I have no explanation as to your low current but your meter is not fast enough to measure the initial inrush, its all over in a few milliseconds. Ohms law doesn't lie, try measuring the coil resistance from spade connector to chassis and then calculate 12 / Ohms. Actually you will have trouble measuring Ohms with a multimeter because its less than 1/4 Ohm, I use a method called a "Drop Test", its where you pass a known current through a resistance then measure the Voltage across it, using this method you can measure very low resistances accurately. I have used an instrument that would measure busbar joints down to 1 millionth of an Ohm (yes 0.000,001 Ohms) but it passed 100 Amps through the joint. You could use a headlight bulb e.g 60 Watts in series with the solenoid measure the current through the coil say 5 Amps, the drop would be ~ 1.25 Volt, easily readable with your average multimeter. Remember the heavy coil is in series with the starter armature, its very close to zero resistance. Of course your current may be low because you have too much resistance in series There is something else you could try with your Ammeter, disconnect the main positive lead to the solenoid, now your inrush current will last as long as the spade connector is powered up, because the starter armature will never see +12 Volts it effectively keeps the heavy current (Grunt Coil) in circuit. The 15 Amp fuse will blow in < 1 second so be prepared to replace that with a 20. Now you have a nice stable current into the solenoid then you can measure the Voltage across the coils and calculate the resistance accurately. One thing that will disrupt your reading is if the motor starts to spin, if that happens the motor will develop what is known as Back EMF (the motor generating Voltage), you should hear the motor if that happens. I had to look this up "D'arsonval movement ammeter", I would just call that a moving coil meter, of course the main current must be passing through a shunt. It's very easy to measure current by passing the current through a copper wire and measuring the Millivolt drop with any $10 multimeter., I'm sure I posted something a while back on that. https://ibb.co/3kkcX7P
  5. I changed all the lamps in mine to LED type, they are much easier to see in bright sunlight. The LEDs should outlast the bike so I glued them in place and soldered the wires direct to the lamp, no lamp holder to give trouble. For the low fuel light I kept one of the incandescent lamps in parallel, this biases the thermistor in the low fuel sensor. As for the trapped fuel on the RH side, I took the pressure relief/return fitting out of the tank and modified it with an internal pipe bent at the top end. The returning fuel is now shot over the hump to the LH side, it still traps fuel on the Right but if you lean the bike right over to the left it has a better chance of staying where the pump can get at it. (I know longer own this bike so don't ask for a picture)
  6. Both coils work together, they both turn on the instant the start relay closes. The "holding coil" is wired between the spade connector and chassis so as long as the spade connector is powered up (Start Relay closed) it's drawing current ~10 Amps. On its own the holding coil will never be able to pull the solenoid in. The "grunt coil" is wired between the spade connector and the motor armature, it will draw up to 50 Amps through the armature to chassis so its potentially 4-5 times as strong as the "holding coil" but only while the solenoid is stroking. As soon as the solenoid reaches the end of travel the main contact closes, now you have +12 Volts on both ends of the "grunt coil" so it's effectively switched out of the circuit. The "holding coil" is strong enough to hold the solenoid in place. While the starter is stationary the armature is effectively a short circuit, the current from the "grunt coil" will tend to start it spinning which generates back EMF but it happens so fast <50 milliseconds it doesn't have time to accelerate. If you get the 50 Amps the solenoid is designed to work with it will stroke in 15 milliseconds. (I have measured this with an Oscilloscope). Of course the solenoid operation depends on the bike wiring being able to feed enough current to the coils, the stock wiring will deliver about 30 Amps on a good day, so working at about 60% of starter design. Another thing that chokes the solenoid down is the tiny wire from the Start Relay to the Solenoid spade connector, it needs to be at least one size larger.
  7. That's a Bosch solenoid but they are all similar, all have two coils from 70s to today. The coils on my VII Sport measured 1.25 Ohms and 0.25 Ohms
  8. Ever since a kid I have been pulling stuff apart to see how it works, and why it don't of course. I carried on through my career as an electrician and instrument technician why should I change now LOL https://ibb.co/JdRY2x0
  9. I guess so, it's quite common in DC coils, other times they have a single coil then add resistance once the magnetic circuit is closed. AC coils don't need that because when the magnetic circuit is open the coil draws a lot more current, once the magnetic circuit is complete the reactance (AC resistance) goes up and the current drops. The factory don't seem to be aware of that, they only show one coil and don't allow for the heavy inrush current. As a consequence the wires and fuse is too small.
  10. Do yourself a huge favour and invest in a battery Voltmeter, these are a simple meter powered by the Voltage its measuring (don't start reading until about 6 Volts). They may not be as accurate as your $400 Fluke but will be within a decimal place and its all relative. https://www.amazon.ca/Digital-Display-Voltmeter-Waterproof-Motorcycle/dp/B09RHC8F1R/ref=sr_1_10?adgrpid=1354598749278790&hvadid=84662606610933&hvbmt=be&hvdev=c&hvlocphy=5064&hvnetw=s&hvqmt=e&hvtargid=kwd-84662659551773%3Aloc-32&hydadcr=15054_10414350&keywords=battery%2Bvoltmeter%2Bgauge&qid=1652968443&sr=8-10&th=1 Get the waterproof one with the convex surface, I have seen them for as little as $3, buy one of every colour and save on shipping cost, give them away to your buddies. IMHO the best place to wire a Voltmeter is across the park light, that only comes on when the ignition is on and the circuit is lightly loaded, don't chop into the main loom, just wire it across the bulb in the bucket using a pair of small wires chopped off an old phone charger, it will take all the guesswork out of your charging system. On my non VII bikes I just pinch an 18 gauge sheetmetal bracket between the handlebar clamps, drill the large hole with a step drill and polish with a buff. You won't be able to read the display in bright sunlight but just shield it from the sun with your glove or read it passing through a shady spot.
  11. It's not easy to measure the solenoid current you'll just have to trust me. I discovered that the solenoid has two coils one day when I was playing around with the 2001 VII Sport I had at the time. I put my meter on Ohms and measured the resistance from the solenoid spade to chassis, I was surprised to find less than 1 Ohm. That particular model VII has a direct feed to the start solenoid from the battery so it never suffered from Startus Interuptus, it would always crank. I did some further testing and found that the two coils measure 1.25 Ohms and 0.25 Ohms and will draw up to 60 Amps for a split second (you can calculate the current by simple Ohms Law 12 Volts / 1.25 Ohms = 9.6 Amps 12 Volts / 0.25 Ohms = 48 Amps for a total of 57.6 Amps (substitute a slightly higher Voltage and it 's well over 60) All Guzzis with electric starters have this double coil but if you look at any Guzzi schematic you will only see one, ask yourself could that be the reason the factory has never cured Startus Interuptus? If you look closely at the spade connector on the solenoid you should be able to see the two coil ends soldered to the terminal. I have pulled a solenoid apart and found each coil has around 300 turns of wire the reason there is such a difference in resistance, the lower resistance 0.25 Ohm uses a heavier gauge wire and it's wound on first so the wire is much shorter whereas the 1.25 Ohm coil is lighter gauge and the wire is much longer as its wound over the top. This heavy current only occurs if there is no resistance in series and it drops to just the 1.25 Ohm coil (~10 Amps) as soon as the solenoid contact closes 10 - 20 milliseconds after the start relay closes. On most bikes you will barely get 30 Amps through the ignition switch and spaghetti wiring so of course the solenoid is only pulling at half strength and waiting to fail. My apologies to Tesla, I will revert to something I learnt as an apprentice back in the 1970s The magnetic strength of an electrical coil is the product of the number of wire turns and the current flow expressed in Ampere-turns a unit not used very often these days . The 1.25 Ohm coil which I call the holding coil (because that's what it does) has 300 turns x 9.6 Amps = 2,880 Ampere Turns, that sounds like a lot until you calculate the other coil 300 x 48 = 14,400 Ampere Turns, so it's obviously doing the Lions share of the work, I call it the grunt coil because it does all its work in a split second, funny that the factory don't acknowledge this coil in their schematics. I'm sure some of you have had trouble with the 15 Amp fuse blowing, this happens as the resistance builds up so now the Grunt coil can't quite get the solenoid to move, it sits there drawing about 25 Amps for several seconds until the fuse pops. Why do the factory supply a 15 Amp fuse? my theory is they measure the solenoid current with a meter ~ 10 Amps, so a 15 would be appropriate, they completely miss the heavy current drawn by the Grunt coil because it happens so fast 15 - 30 milliseconds, too fast for the meter to catch. You can actually measure this peak current by disconnecting the main feed to the solenoid contact, then the high current will be there as long as the relay is closed. You probably think its just a simple circuit, the solenoid just pulls the starter in while the button is pressed but there's something interesting going on when you take your finger off the button, you no longer have power on the solenoid spade but the coils are still powered up via the closed main contact, now the coils are connected in series, current feeds back through the Grunt coil from the motor terminal to the spade terminal and so to the Holding coil to chassis. The thing is because its going backward through the Grunt coil and forward through the Holding coil and they both have 300 turns the fields cancel each other out so the solenoid lets go.
  12. A couple of points. Yes there is normally a Voltage drop between the battery terminal and the Voltage reference of about 0.5 Volts due to the Voltage drop in the relay and socket etc. The OEM regulator is set low to allow for this, I think 13.8 from memory so when you add the 0.5 Volt it regulates at 14.3 (14.3 at the battery to get 13.8 at the reference point) The problem with this is as the relay socket resistance builds up I have seen over 1 Volt drop this can result in the regulator being overloaded as now the battery needs to reach 14.8 Volts Yes, adding headlight relays powered direct from the battery upsets the Voltage reference because you lose the Voltage drop. Yes, the Ducati Energia is a series regulator. it goes Open as the Voltage goes above set point whereas a shunt regulator shorts out the alternator when the battery is over set point. I don't know anything about the Oddessey battery, I thought it was just an AGM type.
  13. P6X, That's very thoughtful but I have one question Since none of the Guzzi schematics show that there are two solenoid coils and the factory only provide a 15 Amp fuse to protect a circuit that can pull up to 60 Amps can you really say they were designed? I put it to you that the factory engineers don't know there are two coils and they measured the current at the solenoid spade terminal with a multimeter, 10 Amps so lets put a 15 Amp fuse to protect the circuit. I have measured 60 Amps there but only for a split second. If its not wired right the current is throttled and as a consequence the solenoid only develops a fraction of the pull its capable of and you get the dreaded click. I also see evidence of the factory thrashing around adding extra relays to try and solve the problem as for example in the later model Griso and Norge 1200s, if they would only draw the coils correctly a light bulb might turn on. Cheers Roy
  14. I just came back from 6 weeks holiday, (central Nth island), unfortunately the computer I had wouldn't access this site. If you are still having a problem we should be able to sort it out fairly quickly. You should have been able to get the switch apart, as far as I know they are all the same, the root cause is probably dried out lube inside
  15. The ECU drain is only microamps, the 525 regulator shouldn't draw anything from the OEM wiring because it's connected downstream of the headlight relay. The black wire acts as a Voltage reference but it also powers up the electronics.
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