Guzzi2Go

True. Diode's UI characteristics is of little or no relevance in this discussion.

It is correct that current through a diode grows exponentially with applied tension. However, it is also correct that the current is limited by the power of the source (alternator). So although growth is exponential, there are limits as to what actually can be achieved. Alternator is rated at 350W, which @12V results in ~30A current. The circuit is fused accordingly. Workshop manual talks about DC 27,5A@10k RPM and I'd say we can safely assume that the regulator/diodes in it are also rated accordingly. Based on that, I don't think we have overvoltage or overamperage problem here. If we had, the fuse would burn out. I'd say the problem is related most likely related to continuos high (but stilll "legal"!!) currents passing through a thermally stressed regulator for prolonged periods, owing to both: - bad battery or regulator-battery connectivity (high currents) - placement of the regulator - behind oil cooler and between cylinder heads. (thermal stress) The main current limiter in the charging circuit is battery's state of charge. If that does not go up quickly (within 15-20 minutes) after the engine is started, regulator will be sweating until it dies.

I have the same pic in my copy of the "V11 LeMans 2002" spare parts catalogue. (Catalogue code: 01 92 00 90, Date of issue: 07/02), sheet I1 showing "Electric system". However, there is another sheet (H13), showing two more relays (ECU + Injectors). Five altogether...

According to the manual, the alternator gives you 15V@1000 RPM and the regulator is capable of giving you 9,5A DC there. So I'd say this is not so unusual. What I find unusual is that the battery is so high after you switch the bike off. However, all the numbers you mentioned are within limits.... Your battery charges high and this is not apparent to the regulator. The regulator will compare the voltage on the black wire (paired with the white for the lamp) against the output on the red wires. Bad black wire connectivity may contribute to "negative perception" of the battery tension. Perhaps to measure resistance between the battery(+) terminal and the regulator's black wire terminal? The current flows through the ignition switch here, so a loss there may explain tension measured lower than actual. P.S. Actually, according to the schema, the connection runs through the headlight relay, not the ignition switch. Guess the manual is not consistent or precise enough there. That would be red-black wire from the headlight relay. P.P.S. Thinking a bit more about it, that does not make sense. The lamp should go on if the black wire is higher than the red wires. No voltage drop between the battery and the regulator can contribute to that.

Going by the lamp alone, one can only say that the tension on the battery is higher than the tension produced by the charger. Could be a glitch, but could be a sign of a malfunctioning regulator. If you have a voltmeter, I'd measure the battery before starting the engine (should drop to 12.6-13V within few hours after ride), then start the engine and measure again. See if the tension goes up and the lamp goes off. If the lamp goes off, rev the engine high and see if the tension goes above 14.6V (upper limit according to the manual). If yes, check the 30A fuse and possibly start looking for a new regulator.

Just to ask, is that with the old RPM sensor, did you just shim it properly, or did you also replace the sensor?

Just to add something... Connecting a deeply discharged and then incompletely charged battery back to the bike is not a good idea. For example, if a battery cannot exceed 75% charge (in my case - 12,6V) on the charger, then it is apparently damaged (a cell shorted?). This seems to put quite some stress on the charger and may cause it to break down. On my Le Mans the charger is placed behind the oil cooler and between cylinder heads, so it is kept cozy and warm regardless of whether current is passing through it or not. Guess that does not help the case either. So as a precaution, I'd say to charge the battery and check the resulting voltage if it has been sitting for long. And then some data on what my new battery can take (Fullriver HC14B, was cheaper than Odyssey), just to get a feel what these things can take: Cold start current - 185A@-18°C (that's Siberia, for Fahrenheit people) Warm start current - 300A@27°C (that's German summer, warm, not hot, rainy and grey) Peak current - 545A@27°C for 5 seconds !!! So quite robust in terms of what one can push through them...

Surprised about leerlauf voltage. A voltage source without load should show nominal voltage. Under load, the voltage will sink, owing to source's low but finite internal resistance. It looks like there is some logic in them after all. They seem to be capable of recognizing that a battery is connected, driving it to 14,3V and as they detect full battery, they may just as well go into some test mode, like mine would. That might explain 13 and a few bobs... My old battery is @12,4V after three days on the charger and two days in the basement. As far as I can tell, the charger never managed to get through the first phase (constant current) and was not smart enough to determine that something might be wrong- Probably thought it is a large battery. In the absence of high-amp charger, another battery may actually do the trick. Why didn't I think of that? It could rush in some serious current and help with recovery. But now I already have a new battery... Still, now I am curious. Off to the garage to see what goes ablaze...

Defo not. It is an el cheapo from our local motorcycle gear outlet in Germany, Louis.de - 39€ on discount. The brand is Saito, the model ProCharger (phased out by Louis, but still available on eBay). Regarding your old chargers, to what current/voltage are they rated? The reason that I ask is that my battery went south over the winter. Tried to charge it, but it would stay @75% for days, even weeks, voltage never exceeded 12.6V. Guess it could be shocked back to life (Dr. House stuff - "CLEAR!!!"), but the charger is to weak for this. The reason why you say that your chargers settle for constant voltage may simply be that the battery needs a shock, but the charger cannot provide it (rated current too low). The voltage will settle for what the charger can provide and the battery will be unwilling to take more charge. This is probably one of the downsides of low power chargers. Here the Guzzi's regulator may come to aid, but it looks it went south too... How much volts do you measure on your old chargers in "leerlauf" without a battery connected.?

Sensors are 'spensive. 169€ @Stein-Dinse, so just on a hunch... I don't know.... But if you say that there is an O-ring below the sensor and that its base plate is bent, then chances are good that the distance is not OK. An O-ring is not foreseen there.

Well, it depends... Day before yesterday I got a new battery, which measured 12.6V as delivered, corresponding to the 75% SoC, as per little paper that came with it. I hooked it up to the charger and measured, 'twas 12.9V. I left it like that for 5-6 hours, when I came back, the maintenance lamp was on and the voltage measured 13.2V. I disconnected the battery and left it over night, when I came back it was 12.8V. Connected it to the charger again and after 2 hours it was 13.6V after an hour more it was 13.9V. Here is what my charger's manual says about the cycle: the charger starts in constant current mode (1A), and waits for the battery to rise to 14,3V then it holds the voltage at 14,3V until the current drops below 100mA then it starts a battery test by loading the battery with a "defined current" (which is nowhere defined , they probably mean a "reference current" ). If the voltage drops below certain level (due to high internal resistance), this is interpreted as excessive sulfate buildup and a recovery mode is started in the recovery mode the charger loads the battery with a current pulse of 80A for 100µs, followed by a charge current limited to 330mA and voltage limited to 14,3V, so here it may well be that the voltage remains below 14,3 for a while. This goes on for an hour. After this recovery mode is finished, a new charging run is started, followed by a test. If the test fails, the battery is faultly (there is a LED for that). If the battery is fine, the charger will maintain 13,8V for one hour. After that, it goes into maintenance mode. If, when in the maintenance mode, voltage drops below 12V, the entire program is started again. Otherwise a current pulse (80A/100µs) is sourced every 30s. Here the voltage can again be under par. After one hour voltage goes back to 13,8V for another hour, and so on... The last two steps cycle indefinitely. As you can imagine, what one measures on the battery depends very much where in the cycle one measures.

Maybe you just caught them at bad time. Charging process goes through different stages, so if you measured too early the battery would still be low or too late and then the maintenance mode would kick in and charger would just be sitting there waiting for the battery to discharge a bit before it starts charging again. And yes, battery guys build their batteries to repetitively drive serious load over longish periods or to be constantly prepared for that. Hence the discussion on how to charge quickly and how to keep them charged. Starter battery in service is neither discharged nor charged "by the book". Whatever chargers can do to a battery is nothing compared with what starter and regulator are doing,

Yes, fuse #3 is the 30A fuse. If you have a big enough Ampmeter or a digital one protected against too high current, you can remove the fuse, connect the ampmeter there and check the current flowing from the regulator into the battery. Dunno how to check the cam sensor. The manual says check connections and sensor's resistance, but it does not say what the resistance should it be. Guess that that kind of a fault would be present at any temperature.

Can you tell if the bike is running rich or lean? What is the color of the spark plugs? If you still believe this is electrical, you may want to disconnect the oil temp sensor. In theory, this should have ECU ignore engine temperature and have it run richer than necessary. See how that goes. Another electrical alternative is engine rev/position sensor (at the front left, above the generator cover), which needs to be properly spaced (0.7-0.9mm) in relation to the toothed wheel. Spacers are available for this.

This is what Odyssey's manual says on the subject: "As previously indicated, deep cycling applications require a minimum 0.4C10 current available from the charger so the values shown in Table 5 do not apply to all products in all applications." The C10 is defined as a 1/10th of the capacity, so in our case: 13Ah/10 *0.4 gives = 520mA minimum charging current. Where it may seem that they contradict themselves is in Table 3, where they state "Battery size and minimum three-step charger current". But that needs to be put in relation to: "...EnerSys® has developed a special charge algorithm. It is designed to rapidly and safely charge these batteries" So the emphasys here is on speed (and safety, nothing will cook or burn), not so much on attaining full state of charge. To that they add: "The charge times recommended in Table 5 assume that the ODYSSEY® battery is fully discharged and these charge times will only achieve about a 80% state of charge. For partially discharged batteries, the charge times should be appropriately reduced. The graph in Figure 2, showing OCV and SOC, must be used to determine the battery’s SOC. The battery should be trickle charged after high rate charging, regardless of its initial SOC" The "appropriately reduced" is related to manual chargers, not implementing any logic/charging algorithm. So if we are to trust all this, I do not really see anything wrong with applying an intelligent low power motorcycle charger giving ~1A max current. The only thing is that the charging will take longer. Next thing to ask oneself is how much value to put on 100% SoC, achieved by occasional charger use. Do we really need that? Especially if a bike starts readily. After all, the bike will give the battery all the amps it needs.

I think more or less everything one needs to know is in the tech bulletin document you linked to in your earlier post. Refer to chapter "Thermal runaway and VRLA battery charging" on page #24. There it says that too high current for too long. may damage (cook) the battery. On page #20 it is stated that the temperature during charging should not rise for more that 10°C, and that deeply discharged batteries should not be charged with more than C/5 Amps. The "unlimited" is mentioned on page #12, "Constant voltage, unlimited current charging", but there it is also stated that: "very high initial current accepted by the battery will cause excessive heating and can be detrimental to the active materials in the plates". What I did not find in the document is that there is a minimum current required to charge this or that.

What do you mean with "regulator be the source" and what do you want to measure with an ordinary multimeter? If you want to measure what regulator gives you, you can pull fuse #3 (30A), start the engine and measure between each fuse socket contact and battery negative. One one side you will have battery's on another regulator's voltage. However, I don't think you can have any spikes coming from the regulator At least not with the battery connected (fuse #3 in place!). The battery would iron out any spikes produced by the regulator. Anyway, the regulator with no (or moderate, there will always be some) load should give you nice 14-14.6V You may want to check your ignition coils, if you have not done that already: https://www.yourmechanic.com/article/how-to-test-a-spark-plug-ignition-coil-by-eduardo-ruelas There are no reference values for coils in the workshop manual, so I suggest you measure both and compare.

Thanks docc, this is a very nice and informative document Must admit, did not read all of it, but still, I think there is some misunderstanding related to these two present: EnerSys (Odyssey) technical reference: “reconditioning charge cycle procedure.” (Amperage is "unlimited", but should not be below 6 amps to *charge* the PC545). #1 is about lead sulphate buildup removal. Not sure if this is really needed with new batteries. "Pure lead" batteries have allegedly very long shelf-life. I assume this means they are resistant to sulphate build-up, at least when new. I may be wrong here, though. "Lead-acid batteries can develop reduced delivered capacity / performance after prolonged periods of storage, especially if the batteries were not periodically boost charged or left on a float / maintenance charger during the time of storage. The cause of this reduced capacity is the development of sulfation of some of the oxide on the plates. " Two ways of achieving this: Have charger drive high current through the battery. This is what Odyssey is talking about in their paper and requires high power charger, practically empty battery and some degree of care - "If the battery gets hot to the touch (exceeds 125⁰F), stop charging and allow to cool". The battery needs to have as low voltage as possible, so the charger would not need to contend with battery's voltage in addition to its own and battery's internal resistance (Figure 3, page #7 of the tech bulletin - assume Rr=0). Have battery drive high current through the charger. Here the charger shorts the battery for a very short period (typically 100µs), generating a current spike of ~100A. Odyssey also talks of this in their chargers data sheet - http://www.odysseybattery.com/documents/ody_chargers_sheet.pdf "Storage recondition mode" The latter is safer if battery is left connected while being charged/maintaned. The 1st method may cause overvoltage and burn ECU or so. #2 Amperage is not unlimited. The amperage is limited by the charger's capacity and that is, in Odyssey's case, 6, 10 or 20A So it is not "not below 6A", it is "not more" than 6A (or 10 or 20). The strategy used by the charger seems to be "Modified constant voltage-limited current" (tech bulletin page 14 and Odyssey's data sheet ), where the charger starts with max. rated current and reduces it as the battery voltage rises. The document also states: "Occasionally, constant current at the C/3 to C/5 rate is proposed as a fast charging technique", C being the capacity in Ah. This gives a hint why Odyssey deems 6A charger sufficient for PC545 (13Ah -> 6A = ~C/2, charging is still "fast"). So this is more about "being quick" than about "doing the right thing for the battery". Comments/responses are welcome.

Back on topic. Did you check air supply? The rubber connecting throttle bodies with cylinders may be cracked and you may be drawing more air then needed.

Hello Kiwi_Roy, the schematics I am looking at (Workshop manual) does not give me that. Yes, there is a red/black wire from the lamps (not only headlight, all(?) lights hang on it too) relay, but that one does not touch the regulator. The regulator is connected to the battery (+) via fuse F3 (30A) and there is a black wire (common ground, in addition to chassis) directly connecting the battery(-) and the regulator. Nothing is "sensed" there, nor does the regulator "decide" on anything. The regulator provides 14.6V "no matter what". Hence the question... BTW, the lamp relay is there to switch the lights off while you are cranking. Give you a bit of extra "juice". Nothing else.

Sorry to say so, but this does not sound right to me... (if these statements have been retracted in the meantime, I apologize for pointing to them "again") The "charging system" on the V11 consists of nothing more than a voltage regulator (not a current regulator, as stated above). In Guzzi's case, it regulates to 14-14.6V on its own terminals (not battery). The voltage on terminals never exceeds 14.6V, If it does, the regulator is faulty. Charging current is theoretically limited by the regulator's voltage, battery's state of charge (voltage on the battery with no load), battery's internal resistance (milliohms range) and parasitic resistance of the wires and connectors between the charger and the battery (also low ohm range), practically however it is limited by the alternator's/regulator's capacity. Max current that the regulator can deliver is 27,5A@10k RPM (~400W). You will need roughly half of that to supply the regular load (150-200W), so not more than 10-15A will be available to the battery at any time. Only battery can blow the 30A fuse, regulator cannot. If it's blown, there is a short southward of the battery/fuse. Docc, where did you find that info on "battery priming"? Odyssey is quite explicit on "never exceed 15V" and their charger's documentation also does not provide any statements on high current/voltage spikes. Can you perhaps post a link to a document? I know my comment is more than a year late and I sincerely hope it does not spur a flame war. This is definitely not the intention.

Curious here... What makes you say that?

Sorry for joining the party late (still hang over from the last one), but I am just looking at this thing as my bike also tends to go out and/or won't start from time to time. The main symptom is identical - the pump does not prime. Also, want to use the opportunity to cross check with other members here if I am missing on something... The pump is primed via relay #46 (Injector relay, numbers from the page 5, section P of the Worshop manual), which is in turn primed via relay #49 (ECU relay) and that one switches on only if either side stand switch #40 logical-OR neutral switch #13 driving relay #15 is closed. The next thing then is that the engine cutoff switch #36, terminals 1 and 3 of connector #35 must be also be closed. If it isn't, no power anywhere from pump to starter, though lights will work.. There is also a bullet connector #57, White-brown wire between the start switch and the relay #49. So I'd say if the pump does not prime AND pushing starter button (clutch pulled, switch #17) does: - NOT turn the engine, look at switches #17, #40 and #13 and relay #15. - turn the engine, look at switch #36, relays #46 and #49, connectors #35 and #57. Would that be right?

I developed the same problem when riding my Mille GT back from Sweden to Germany back in 2006 (or so). A small leak I noticed first tank stop after Stockholm grew into serious leak by the time I reached Copenhagen, rear tire being completely drenched by then, luckily only the sidewall. Had to buy a can of oil and top up every tank stop till Düsseldorf. These things can go quick. Fix was easy. 2€ + sixpence for the seal, swingarm down & out, fishhooked the old seal out, punched a new one in using a plastic canister cap. Piece of pie!

This & That. WTF?