Kiwi_Roy

I got a call from a friend with a VII Sport a couple of weeks back, he has owned the bike since new and done all the regular maintenance. He said the oil light came on for no reason at idle, could I come and have a look. He had the sump off when I got there, we couldn't see anything so concluded it must be a failed pressure switch and decided to put it back together. He would change the filter while it was apart. We took the hose clamp off the filter and screwed it off with a struggle. To our surprise it came off complete with a second rubber gasket all chewed up, It must have been working fine for months then finally given out while sitting waiting for parts. We concluded that the engine was fine and thanked his lucky stars.

A starter motor is almost a short circuit so if it locks up its probably pulling 250 Amps or More, I measured the starter on my VII once and found it drawing in the 150 - 170 Amp range. Any DC motor with brushes is also a generator, as it spins its producing a Voltage in the opposite direction to the battery, this is known as Back Electromotive Force (Back EMF for short), the faster it spins the less current it draws. Of course if its not spinning the only thing the limits the current is the load resistance and the batteries internal resistance. Its quite easy to measure the starter current all you need is a shunt made of regular wire and a cheap multimeter with a millivolt range. I'm sure there's a copy of my home made shunt sketch on here somewhere.

Didn't the early ones 2001, 2002 have Siemens relays, I was talking with a guy yesterday who had one new back then and he pointed out the early relays weren't the best, When I bought my 2001 it had several brands of relays Siemens included, the first thing I did at your suggestion was swap in a new set of Omrons and I never had a problem, on the same topic my bike started to run rough one day, I pinned it down to the ignition switch that was measuring ~18 Ohms, still cranked ok, even 1/2 an Ohm would cripple a 2004 with start relay through the switch Look at how the start relay 30 terminal is fed on this early version, straight from the battery through fuse 5, this will always crank. (solenoid pulling 50+ Amps for a split second) On the other hand powering the headlight relay from the normally closed Start relay isn't a good idea. Now look at this 2004, the power for the start relay comes from the ignition switch choking the solenoid to a fraction of its former self (< 30 Amps for seconds) and leaving it prone to Startus Interuptus It does have a better feed to the headlight however and they did away with the flaky Voltage reference to the regulator. Because this model uses the Normally Closed Start relay contact it rules out simply re-powering the relay 30 contact to fix the starting, there are a couple of ways around that.

The earlier bikes took a direct feed from the battery to the start relay so the relay could feed the solenoid coils about 50 Amps. all the ignition switch carried was about 6 Amps. I think about 2004 Guzzi changed the wiring to feed the start relay through the ignition switch so now the switch and wiring has to supply the solenoid coils, I doubt you will get more than 30 Amps on a good day, all kinds of Voltage drop through the switch and wiring. Net result 30/50 or 60% of the magnetic field the solenoid was designed to supply, would you be happy if your Guzzi engine only put out 60%? When the solenoid current drops a bit further through dirty contacts (around 25 Amps) the solenoid doesn't even try to move, eventually the 15 Amp fuse blows. As soon as the solenoid main contacts close the coil current drops to just 10 Amps, it doesn't take much to hold the solenoid in place because the gap is small but it takes a super strong magnetic field to get it to start moving when the gap is large. There are 2 coils in the solenoid The holding coil 300 turns of fairly light wire drawing 10 Amps 3,000 Ampere Turns The Grunt coil 300 turns of larger wire wound on next to the core so as well as being fatter its also much shorter drawing 40 or more Amps 12,000 Ampere Turns. (4 x as strong) Ampere turns is the way of expressing the magnetic field strength The best way to prove it to yourself is start the bike a few times normally then take a wire and feed the solenoid directly by touching the wire direct to the battery, on your 2005 the solenoid will snap in at least 3 x faster. BTW, a good battery will hold about 10 Volts while cranking but while the solenoid is stroking the Voltage should be over 12 because the contact is not yet closed. I've tried every way I can think of to explain Startus Interuptus, I guess I will never make a good teacher lol

If you carry under the seat a jumper cable about 3 ft long with a spade connector on one end and a bare wire at the other you can always slip it on the solenoid and touch the battery positive with the other. This will send 50 Amps to the solenoid and the starter will engage and spin. Just be careful to make sure the bike is in Neutral and pull the clutch for good measure. As well as starting the bike this jumper proves that the battery and starter are ok but of course if the battery is flat, disconnected or the starter is toast nothing will happen. I always found my VII Sport easy to bump start in 2nd gear.

IMHO you must provide a decent ground cable to the regulator case, all the current that passes through the red wire to the battery has to find its way back from chassis to the regulator case, the tiny black wire all the way back to the battery doesn't cut it. The Ducati Energia regulator doesn't directly control the battery Voltage, it regulates the Voltage between its black wire and case ground to 13.8 Volts so if the case is not connected to battery negative properly the Voltage you drop between negative and the case is lost. Probably when the bike was new it made fairly good contact to chassis but as it ages it has to rely more and more on the thin black wire. The path through the engine to the main ground connection to the battery is many times better than the black wire. A short heavy wire from the regulator case to a timing cover bolt is a vast improvement. I have even suggested using an aluminium strap in place of a wire with suitable grease to stop corrosion of course.

Marty, thanks for the research. I did a really interesting experiment a while back with a mixture of Sulphuric acid and an organic known as Nitrobenzine. The two solutions were mixed in a beaker with lab stirring system so it was a homogeneous mix. I started out with a 50:50 mix and kept increasing the acid ratio. All of a sudden the solution went from an insulator to a conductor. The process engineer I was working with explained that the solution flipped from drops of acid separated by an oil film to drops of oil separated by an acid film. I played around for a couple of days trying different combinations, the funny thing once it had flipped you had to decrease the concentration by about 20% before it would flip back.

This is because there is not enough current flowing through the coils probably 20 - 25 Amps. the solenoid is just sitting there, eventually it melts the 15 Amp fuse. The coils are designed to draw over 50 Amps but going through the ignition switch even a clean one you will be lucky to get 30 Amps barely enough to encourage the solenoid to move. The strength of an electromagnet is proportional to the number of turns x the current flow so at 20 Amps its only pulling at 40% of its design strength. The dashboard lights dim because you are pulling a lot of current through the switch and the contact resistance is dropping the Voltage, if you clean the contacts you will find it improves. After a few years the Vaseline in the switch gets hard and tends to hold the contacts apart, On a cold day it will be even worse because the vaseline is even harder. Clean the old vaseline out and replace it you will notice a vast improvement. If you really want to fix it you need to provide a better source of 12 Volts to the start relay however with the later VIIs you can't just feed 12 Volts from the battery to the start relay as you can with most other Guzzi because the Normally closed 87A contact goes to the headlight. There's another easy way and thats to add another relay with the contact between the large live terminal and the spade connector, The new relay coil is triggered by the original wire that went to the solenoid spade, you also need to ground the other coil connection. Now all your switch has to supply is about 150 milliamps, the solenoid will pull ~ 60 Amps and the starter will perform how it was designed to. Notes: A fuse is optional, it should be 20 Amps because you have doubled the solenoid current. Although the current is much higher the duration is much shorter so it doesn't have time to heat the fuse (typical 15 milliseconds at 50 Amps then it drops back to 10 Amps) The starter designer never intended it to be installed the way Guzzi do it.

This is a very good explanation of the bullet connector problem, My 01 VII Sport would suffer occasionally but it never got so bad I had to fix it.

That was a lucky find, I remember Docc telling us about that years ago. The two bullet connectors (60) connected to the clutch switch (17), I think that's a common fault. Also on high milage bikes the wires work harden and snap under the insulation where they constantly bend back and forth around the headstock, you can find the broken ones by pulling hard on them one at a time, if they stretch the copper core is broken.

The starter solenoid will draw at least 30 Amps while it is pulling the gear into mesh, I doubt any of the wiring is up to that, first off they start with a 15 Amp fuse then send the juice all the way to the front of the bike and through some tiny wires to the ignition switch and back, I doubt the ignition switch is rated at much more than 10 Amps and it increases in resistance with age as the grease goes hard. When you do a Startus Interuptus fix you bypass all this wiring and the solenoid will likely draw 50 Amps and operate 5 times as fast engaging with a healthy clunk. The fix most recommended was to feed the starter relay with a feed direct from the battery through a fuse bypassing the ignition switch, this caused a few problems for owners not familiar with wiring, Lately I have been suggesting adding an extra relay mounted near the starter, one side of the contact is fed from the large live terminal, the other contact goes to the solenoid spade terminal. The original trigger wire goes to the new relay coil while the other coil terminal is grounded. Doing it this way the bikes loom stays original, no logic is changed.

I don't know of any grease that actually conducts electricity, take your multimeter on Ohms and see, take a picture and post it here if you find a conductor. Vaseline has been used by electricians for 100 years or more, its especially good on battery terminals and ground connections, what it does is protect the metal from Oxygen, no Oxygen = no Lead Oxide. Lead Oxide is an insulator, you can prove this to yourself by touching your Volt meter leads to the battery posts, chances are if you haven't scraped them clean you won't get a connection until you jab the terminals through the oxide layer, on moving contacts Vaseline lubricates the contacts to stop them wearing. I swear by this stuff, I never work on bike electrics without it. I dip wire in it before I crimp a lug on, they never corrode that way. Actually any grease will deter lead oxide formation, Vaseline is cleaner than most. I wouldn't use Dielectric grease i've seen too many bad reports on it, I have no personal experience because I never use it, I believe its good for plug leads however, I would use it there. The starter current doesn't pass through the ignition switch, it's the current to the starter solenoid coils this can be over 50 Amps for a split second. Once the solenoid pulls the gear into mesh and the main contacts close it drops to about 10 Amps. If your dash lights are dimming it's either too much resistance in the switch or a bad battery or ground connection. It could be the battery of course, the test below will check that. The easy way to troubleshoot the starter is to take a wire and touch one end to the solenoid spade connector and the other to battery positive, if it cranks that proves the battery and starter are both ok. Do this with a Voltmeter across the terminals and it should hold around 10 Volts while cranking. A word of warning, make sure the bike is in neutral or the starter will launch it.

I'm slowing down with age, probably take me 20 Remove the two Phillips screws that hold the switch onto the lock Tilt out the white contact plate by releasing the odd clip Wipe off the old grease with a shop towel Add fresh Vaseline Replace the contact plate Screw it back on While you are there fasten the wires where they come out the back cover so they don't flex at the solder joints and snap off. You should disconnect the battery Negative but I never do.

Startus Interuptus (solenoid clicking without turning) happens when the wiring cannot deliver enough current to the solenoids 2 coils so its not able to pull the gear into place. (the slow starter rotation is something else altogether as you have discovered) The early VIIs were wired with the battery going direct to the start relay so they had no problem delivering 50 Amps to the solenoid. Later bikes routed the start relay through the ignition switch, you are lucky to get 30 Amps through that wimpy device that's why it needs cleaning to make sure it can deliver maximum current. At 30 Amps it's only working at about 50%. The starter manufacturer never intended it to be wired that way, they want the solenoid current as high as possible, I sometimes wonder if the factory know how the solenoid works. For example try to find a factory drawing that shows two coils. Just about every other Guzzi model is also wired wrong, I see my 76 Convert has been corrected at some stage. Note this high current is only for a split second, just while the solenoid is moving, once the main contact closes the second coil is switched out and the coil current drops to ~ 10 Amps

I think these meters are based on a Hall Effect sensor, I will keep my eyes open for one, In the meantime I will measure my DC Amps with a shunt that cost me nothing to make, Guzzi Content. As an apprentice we had a DC clip meter that had an analog scale, it had zero wiring but relied solely on the magnetic field around a wire and had selectable ranges by taking one movement off and substituting a movement with different sensitivity, quite expensive though. You can increase the sensitivity of these meters by putting several turns of wire through the jaws, its a straight relationship between the number of turns and the reading. I like electrical meters and I have a few quite rare ones.

Yes, that's the other one, My VII Sport was grounded to thereat release switch, I noticed it was slow to crank one day but fortunately I figured out what it was before that happened.

AC/DC clip meters are a fairly recent innovation, we have had AC ones for eons, but they won't measure DC, I haven't seen one that cheap yet. However multimeters with a DC millivolt range have been around forever almost. Heres how you can make a simple shunt, a #12 option will easily measure 200 Amps drawn by a Guzzi starter https://ibb.co/3kkcX7P If you live where cable sizes are in metric you will have to figure out the meter spacing, its very easy to do. 1, Take a length of wire, a meter or more. 2, Bare a spot near each end, these are where your meter will connect. 3, Pass a known current through the wire from each end (outside the two bare spots, measure the Millivolts 4, From the known current and millivolts you can calculate the distance between tapping points you need to get 1 millivolt per Amp Note: If you don't have a meter with Amp range you can use a high Wattage lamp on 12 Volts to give a fairly close approximation. e.g. 60 Watt headlight bulb 60 / 12 = 5 Amps, your meter should read 5 Millivolts. You must not connect your meter at the same point you connect the current you are trying to measure, the joint has a much higher resistance than the length of conductor, your meter would read too high.

Probably the ground to the ECU, This will fry pretty quick if you try disconnecting the battery terminals in the wrong order then accidental let your wrench touch the ECU Always disconnect the negative terminal first, reconnect it last that way there is no return path to fry little wires,

John asked me to look in on this thread, I used to know quite a bit about these systems. Firstly the alternator wires can be a problem, they snap off where they solder to the coils. When this happened to mine the copper was so corroded it was not possible to re-solder them so time for some new wires, its quite easy to solder the new copper to the coils. The bullet connectors where the regulator plugs into the stator leads often overheat, if this is a problem just chop the bullet connectors off and join to the alternator with crimp links or a solder joint. Grounding the regulator is critical, all the charging current travels back from the chassis to the regulator case so it can return to the alternator through the other yellow wire. The factory supply a small black wire from the case all the way to battery negative but this is far too small for the current involved. Run a short wire from the regulator case to a timing cover screw, the engine and battery main ground are massive compared to the tiny black wire. The regulator has a rectifier set up as a bridge, 2 diodes and 2 Silicon Controlled Rectifiers. The rectifiers sometimes go open circuit, this situation is very easy to set for if you have a meter with the diode test function, The diodes are connected from each yellow wire to the red wire, it should show about 0.5 Volt, since the diodes are between each yellow wire and the red pair its possible to add a diode on the outside. The way they measure the battery Voltage is very poor, it taps off the feed to the headlight after the headlight relay and in some cases a normally closed contact of the start relay. The relay contact and socket resistance changes with time, the Voltage drop can be anything from 0.6 to 1 Volt, I have a theory that the reference voltage drop approaches 1 Voltmeaning the battery Voltage has to be pushed above 15 to supply the regulator reference, this high Voltage demands more current which overheats the diodes unit the leads melt off. A warning sign can be the headlight out or the tachometer not working, chances are the battery is not charging and of course the charge light also fed from the headlight relay won't be working either fooling you into thinking everything is ok. I often thought of getting the Voltage reference from a different source downstream of the ignition switch, off one of the ECU relays or from a dedicated relay direct from the battery. This would give the regulator a lower Voltage reference because it expects a drop through the relay but it could easily be compensated for with some resistance ora diode in series. I struggled with this flakey Voltage reference for years then I upgraded to a permanently connected regulator from Electrosport, there was one minor drawback a parasitic drain on the battery, I used to disconnect the regulator over the winter but if you don't remember to re-connect it next thing you know the bike dies with a flat battery. Electrosport recommend their ESR515, I dont agree, it still relies on the flakey Voltage reference and a good ground connection. I used the ESR510 it is wired direct to the battery and it has a dedicated ground wire I don't think it supports the charge light. Instead of a charge light I recommend just purchase a battery Voltmeter for ~ $15 and hook it downstream of the ignition switch this will leave you in no doubt. https://www.amazon.com/12V-Voltmeter-Color-Digital-Display/dp/B07HHTZ1L5/ref=sr_1_46?dchild=1&keywords=12+volt+battery+meter&qid=1633586264&sr=8-46

Any $10 multimeter with a millivolt range can measure the starter current if you make a shunt for it.

Hi Jim, Unfortunately if you run a direct feed to the start relay of this bike it results in the lights coming On with the key off as you describe because 87A is alive with the key Off. Most other Guzzi models use a 4 pin start relay or leave the 5th pin un-used. There are a couple of ways around this 1) Restoring the original 30 feed from the ignition switch and adding an extra relay triggered by the existing trigger wire to the solenoid, this seems to be the way you are leaning at the moment. I would put that relay down by the starter and feed it's 30 contact with a 20 Amp fuse from the large solenoid hot terminal. The nice thing about this method is you don't really need to alter the original loom, the wimpy feed and tiny wires are perfectly adequate to supply the new relay coil. 2) Supply a direct feed to 30 (as you did) but clip the wire off the Start relay 87A contact and re-direct it to the wire you clipped off the Start relay 30 so now the ignition switch turns on the headlight relay directly (but now the headlight doesn't switch off while cranking). To get around this cut the ground off the Headlight relay coil and extend it down to the large terminal of the starter solenoid, not the live one but the one that goes to the starter motor. Now while the motor is cranking both coil terminals of the headlight relay are at 12 Volts so the relay drops out, when not cranking the relay coil is grounded through the starter motor. I'm not sure why you cannot get the ignition switch apart, First of all you only remove the two Phillips screws underneath the steering head to let just the contact block drop off leaving the lock in place. Tilt out the white contact plate by releasing the odd clip of the switch barrel. Drop off the battery Negative to make it safe or unplug it at the headstock. Putting it back, fasten the switch wires to the rear cover so the wires don't bend and snap where they are soldered to the switch plate. BTW A dirty ignition switch is often the prime reason for "Startus Interuptus", the Starter solenoid can draw up to 50 Amps for the split second while the gear is engaging, there are two coils in the solenoid not just the one the factory show, the Guzzi wiring and weak ignition switch chokes the solenoid through wimpy wiring to less than 30 Amps so it performs badly. With a direct feed the starter will engage 2-3 x faster.

Sounds like the ECU relay is not getting a signal to turn On See how Fuse 8 has 12Volts on it when the key is turned On If your bike is a later one without an electric petcock you can measure the Voltage at the ECU relay base and chassis Possibly the side stand relay. Check you have the right polarity on the battery, if that's wrong the ECU relay won't pull in but the starter will still crank.

What does the John Deere have to do with anything?

As Docc says I would suspect the ignition switch, when's the last time you cleaned the contacts? If you wire a small lamp to the petcock fuse F8 you may see it go dim or flicker confirming that there is a bad contact somewhere between the ignition switch, kill switch or side stand relay.