I've a question for you guys regarding motorcycle electrical systems. I have unintentionally started a bit of a kerfuffle on another board about this. I have no feeling which way is correct so I am not trying to bolster MY opinion, I just want to know what the right answer is. There are 2 schools of thought on the other board and it is related to the consequences of taxing an electrical system using heated gear that draws more power than the system puts out.
Theory 1. Taxing the system causes the stator to work too hard causing its rapid failure.
Theory 2. The stator works at 100% all the time regardless of load. It generates electricity that is used by the bike and any excess electricity is sent to the regulator/rectifier and dissipated. In this theory, the only consequence for taxing the system is that the heated gear will gobble up all of the available juice and pull whatever else it needs from the batter; the end result being a drained battery but no damage to the system itself (other that whatever damage is caused to the battery).
This is all coming from a question I asked about if a Suzuki TU250X will put out enough juice to run my heated gear. One guy said don't do it, you'll fry the stator and the other guy said you can do it but might drain the battery.
What do you guys think?
Mark
It doesn't matter what I think or what guys on other forums write - what matters is what Howie, Ducatigirl, Nick, Suzyj and the other DMF gurus say [thumbsup]
That is why I am here Stop!!!! ;D
I can see either theory being correct; but being an electrical idiot savant (minus the savant) I thought I'd ask those folks!
Mark
The key problem here is, I don't know exactly what kind of charging system is on that Suzuki.
The Ducati setup, the stator runs at 100% at all times.
When the engine is running, the charging system delivers about 20 amps to the various electrical devices on the bike.
That's for an IE, carbie would be less, though I haven't measured it.
On top of that, there's current that goes to recharging the battery.
Anything left over is dissipated as heat by the stator and voltage regulator/rectifier.
As long as your added load is less than the left-over, you're all good.
The usual problem is if the bike spends a lot of time idling, as in heavy traffic or city riding, the left-over at idle isn't a lot.
And if it's used for short trips, or a lot of startup/shutdown cycles, there's more consumed in recharging the battery.
Well that is answered. Most motorcycles, and probably yours operate as Speeddog described. Exceptions are BMW boxers, Moto Guzzis and some tourers. What you need to know, hopefuly it is in your owner's manual, what your charging system output is. Then add up the amps used by the always on circuits, i.e. headlight, fuel pump, etc. Using the rating for the fuse on that circuit will give you a nice margin of error. What is left over can be used for accessories. Do keep in mind at low engine speeds output is notably less.
Usually small bikes do not have very large charging systems. Gyde by Gerbing makes some good lithium battery powered heated clothing that is perfect for commuting, such as this
http://uniongaragenyc.com/shop/heated-gear/gyde-by-gerbing-7v-heated-torid-softshell
Sorry guys, I should have been more clear on what I am looking for in this thread. My heated gear requires about 8 amps and the consensus is that the Zook only has about 5 to spare, so as a result of that on the days that require heated gear I'll be riding my DUC.
The question I have is this (and Speeddog touched on it a bit): If I WERE to run the heated gear on the Suzuki and pull more juice than the stator makes do I run the possibility of DAMAGING the stator or will the deficit simply be made up for via the batter and "no harm-no foul" (other than a possibly dead battery)?
It is a theoretical question rather than "can I run my heated gear"; I am just not going to use it on the small bike.
Mark
More likely you would kill the regulator.
AFAIK, no risk of damage to the charging system, just running the battery down.
Quote from: Speeddog on February 08, 2017, 04:51:21 PM
AFAIK, no risk of damage to the charging system, just running the battery down.
That's my thinking also.
Thanks for the input folks!
Mark
Go on amazon and pick up a small waterproof digital volt meter like I use on mine. It was like 11 bucks. I mounted it below the gauges above the bar mount on my 96. Worth every penny.
Also, you should look into a mosfet regulator rectifier upgrade kit on eBay if you have an older monster. My voltage jumped up from just over 12 volts while riding up to around 13.5 with no load. With my heated gear (Gerbings jacket liner and gloves) I'm still at a very comfortable 12.5 volts while riding.
Having a voltage gauge will also allow you to monitor the battery and regulator/rectifier condition and if something does go wrong such as a failure of the regulator, you'll notice it long before your battery ruptures...
(https://uploads.tapatalk-cdn.com/20170210/8abb9e2e1db3303b3ead0a3e81235f22.jpg)
This is an interesting discussion. So, if the stator is already generating its full load current all the time, and excess is dissipated partly by the voltage regulator, is it actually good for the regulator to run say a heated vest so that the energy from any excess current is dissipated by the vest and not the regulator? would the regulator run cooler when I'm wearing a heated vest? Sounds counter-intuitive but that may be the way it is?
If the stator is running at full load all the time, does the stator produce the same current at 5,000 rpm that it does at 8,000 rpm? That's also counter-intuitive. From what little I know about rotors and stators and magnetism, I though the output is directly related to rpm and more current (and heat) will be produced the faster it spins. What is it that regulates the stator output if it isn't regulated by the VR?
Our standard Duc regulators aren't as bad as Lucas but not exactly known for reliability. When they fail, what is the typical cause of the failure? Getting hot from dissipating too much heat?
Do the MOSFET regulators such as the Shindengen that SuzyJ uses somehow actually regulate the stator current produced according to demand? I think this question has been answered several times in other threads.
Sorry about all the questions. I sort of instinctively understand things like bearing clearances and oil, not so them little electrons.
Thanks,
Bob
OK, let's start with output. Both voltage and amperage will go up with speed up to maximum output which is bases on the stator windings. The stator should be designed so this happens at cruising RPM, so amperage is relatively low at idle. So is voltage, but as long as it is higher than battery voltage while running that is OK. Amperage, assuming proper engineering was done, is high enough at low speed to run all the electrics on the bike from the factory that would be constantly on. If I remember correctly, maximum output on our bikes happen at 3K RPM.
The voltage regulator on our bikes have three jobs; regulate voltage to 13.5-14.5 volts, shed current (amperage) not used as heat and rectify AC to DC. Typical failure is from heat, and, IMO from lack of air cooling and not using Mosfet transistors. I've seen them physically overheat and have electronic failure, either transistor or diode. Mosfet transistors run cooler and handle high current better. Mosfet regulators do the same task, just more reliably. It is worth mentioning Rick's Motorsport Electrics and Electrosport regulators are Mosfet. Would reliability be increased by increasing load so less current is turned to heat? I do not know, but I think the answer is what the weakest link is in that specific system.
The way you regulate current output of an alternator directly is by changing the magnetic strength of the field, which would require a rotor that is a winding not a permanent magnet. The more amps fed in the higher the output.
Gotta say my old 750 with 8?K miles on it still has the original regulator, so it all that unreliable. It is also worth noting the older Monsters had the regulators up front in the airstream.
Hope I answered some of your questions.
Bob,
I am no-where near an expert, that is why I asked the question, but I do know that as the RPM's pickup the power output of the stator does increase; now whether it is volts or amps that increases I don't have a clue. But the key is (I think) that the stator will not work HARDER with an increased load. If the stator puts out X amount of power and 3000 RPMs and Y power at 6000 RPMs that will never change regardless of electrical usage.
Interesting thought on the heated gear actually lightening the work load of the regulator rectifier, I had never thought if that!
Mark
Howie,
Thanks for taking the time to post your detailed explanation.
Mark,
You asked the original question but ended up doing some good explaining yourself.
Also, ductiderinct's suggestion about the ebay/amazon volt meters is a good one.
Thank you Bob! Being a very non-technical person I thought I'd give a shot at explaining what I have learned from this thread and one on another forum.
I wish I understood more/better, but my brain starts to get overloaded pretty quickly when talking about electrical stuff.
And I would have bothered responding after reading Howie's reply, but we were doing it at the same time!
Mark
I just replaced my regulator/ rectifier on my '98 M900. This is the 4th one in 37000 miles. (original, a used one off a Grand Canyon, + the Ricks one all failed). The last one was a 2 yr old Ricks' and I don't think it was the mofset kind. Their newer ones appear to be so. With the last one (Rick's) , the stator connectors to the R/R were smoking and hot all the time. When tested via Electrosport's directions its' 2 reverse diodes had failed. I just installed a new Shindengen Mofset from roadstercycle.com With my Shorai lithium battery it's 13.8 volts at the battery while running now, a little less when off. All good now. No hot connectors. I plan on increasing the stator wire gauge at some point all the way to the inside of the stator, maybe at the next oil change. Currently my old oem stator wires go up to the new, long R/R's 3 wires. I ordered the new r/r w/ long enough 3' stator wires that are coiled up for now.