re[2]: [dsn_klr650] electric output?
Posted: Sat Nov 22, 2014 3:47 pm
#ygrps-yiv-2076168924 blockquote.ygrps-yiv-2076168924cite {margin-left:5px;margin-right:0px;padding-left:10px;padding-right:0px;border-left:1px solid #cccccc;} #ygrps-yiv-2076168924 blockquote.ygrps-yiv-2076168924cite2 {margin-left:5px;margin-right:0px;padding-left:10px;padding-right:0px;border-left:1px solid #cccccc;margin-top:3px;padding-top:0px;} #ygrps-yiv-2076168924 .ygrps-yiv-2076168924plain pre, #ygrps-yiv-2076168924 .ygrps-yiv-2076168924plain tt {font-family:monospace;font-size:100%;font-weight:normal;font-style:normal;} #ygrps-yiv-2076168924 a img {border:0px;}#ygrps-yiv-2076168924 {font-family:Tahoma;font-size:12pt;} #ygrps-yiv-2076168924 .ygrps-yiv-2076168924plain pre, #ygrps-yiv-2076168924 .ygrps-yiv-2076168924plain tt {font-family:Tahoma;font-size:12pt;} If one wishes to improve their Gen1's output...should be the same for Gen2 but don't recall if I've measured... The maximum output from a stator is limited by what we techs call "hysteresis loss". I qualify the context of the term in the hope that someone will explain if it is not a technically correct use of the term. It's sort of like the apples and oranges conversation with someone who thinks that the colloquial definition of "theory" which means something like: "just someone's unsupported idea" matches the scientific definition which means closer to what lay people would call "proven fact". The hysteresis loss referenced here describes that the current flow in the stator wires creates (induces) eddy currents in the rotor and in the stator's iron core. These eddy currents create their own magnetic lines of force which counteract those of the rotor magnet, reducing the magnetic strength and so reducing the output. At some point a balance is reached beyond which output does not increase. One will not increase the alternator's maximum output by reducing resistance and such practices unless the resistance is extremely high. If one introduces some resistance into a stator leg, the voltage will simply rise to continue to deliver about the same current. In practice, for example, people will notice a significant voltage drop in the KLR's White Wire circuit and conclude, "Ah, ha! By Ohm's Law I can reduce the voltage drop and so increase the current output from the alternator!" Increasing the wire size does reduce the voltage drop but current flow does not increase. Everyone will already know that the KLR uses a shunt type VRR and some have replaced by an FH010, FH012, etc. which are series type. Again, going to be long winded in case someone doesn't have a working knowledge and hoping for correction or improvement to the explanation. The VRR Voltage Regulator/Rectifier does two jobs: one is to rectify or convert the alternating current or AC produced by the stator to direct current or DC needed to charge the battery and to power electonics and motors; the second job is not really to "regulate" the voltage but to limit it to a set point. In other words, the regulator isn't able to increase voltage if needed but simply stops it from becoming too high. There are a couple of interesting (perhaps only interesting to those of us who are too easily amused?) effects regarding the VRR: one is that the battery requires a lower voltage in order to charge when hot than when cold. For this reason, more advanced systems have some designed means to reduce charging voltage in order to avoid over charging the battery and driving off water and electrolyte acid through gassing. Some automobiles used a sensor at the battery to inform the voltage regulator but the KLR is not so advanced. The other effect is that electronics tend to increase in resistance with heat so that a VRR will generally produce a lower output voltage when it is hot. If VRR and battery are nearby they can "cooperate" in this regards. Ever notice that your bike's battery uses more water in the summer? That's why, hot and over charging some degree. So, the two types of VRR both contain a rectifier but there is an opportunity here. Most rectifiers in past years have used silicone diodes in a diode bridge to rectify AC to DC and as we have seen, reducing series resistance in the alternator output circuit does not increase maximum output, generally speaking. What is generally overlooked however is that most of our concerns regarding charging/alternator output are not tied to maximum alternator output because the times in which we see the alternator not keeping up is around town and on the trails when the bike is idling or other low RPM. In this case it wouldn't matter what was the maximum alternator output because we aren't getting that. In fact, as I tried to describe in a previous post, a larger output alternator may make this worse rather than better. So, we are losing battery charge in the around town so what to do? Here is where alternator series resistance can have an effect. The alternator's moving magnetic lines of force created by the magnetic rotor push against the electrons in the stator winding wires. The amount of push is what we call voltage and it is similar to the push which a pump applies to water in a pipe. The moving magnetic lines of force apply a certain amount of push which must overcome resistance to flow in the circuit. The greater the push or less is the resistance, the more current flows. That's what we might have expected from maximum output were hysteresis loss not getting in the way. Where we can make a gain is if we can reduce the resistance in the alternator output at lower RPM when the alternator is less affected by hysteresis loss. In this case, we can do some small bit by modifying the White Wire circuit as I have described elsewhere but the big gain is in the VRR. Everyone will recall from their high school science that a silicone diode offers about 0.7 volts of series resistance so, since each "leg" of the stator flow is through two diodes, there is a loss/voltage drop of 1.4 volts, in theory. If one could reduce this to say, 0.4 volts drop then one would be seeing 13.6 volts (and charging a bit) at that stop light rather than seeing 12.6 volts (and discharging the battery a bit). This over simplifies as some will note but the explanation is intended to illustrate the effects. Here's where it gets interesting, IME. People will sometimes try to use diodes as a means to drop voltage by a fixed amount by adding diodes in series. 0.7 volts drop times ten diodes should drop 14 volts bike voltage to 7 volts to run a six volt device, right? Try it and is will be seen to work so long as there is no significant current flow through the diodes. When a diode is conducting near to its maximum current, the voltage drop is more like 1.4 volts than to 0.7 volts. So, when the VRR's silicone diodes are actually rectifying current, they present more than a mere 1.4 volts drop. What to do? When I first began looking at this problem in decades past, the solution might have been to use germanium diodes which have much less resistance, which is why they were used in the antenna circuits of early radios. Remember your germanium crystal radio? Replace that crystal with a germanium diode and the radio worked as well or better, but stick in a silicone diode and not working. VRR have moved ahead in using a different system for rectification, MOSFET transistors. MOSFETs have very, very low resistance so simply replacing the original silicone diode rectifier shunt VRR with a MOSFET rectifier shunt VRR increases lower RPM output to a useful degree, IMO. These shunt type VRR units can be purchased for quite modest cost off EBay or other sources so not a big investment. The ones I have chosen are also physically larger in size so they have more cooling capacity. The combination of greater cooling and less heat due to lower rectifier resistance keeps output up to a useful degree according to my measurements. Here's an example of the VRR I've used on some Gen1 KLR and some Suzukis: http://www.ebay.com/itm/Mosfet-Voltage-Regulator-Rectifier-Suzuki-Boulevard-GSXR-Bandit-2003-2011-/331390229849?pt=Motorcycles_Parts_Accessories&hash=item4d28659d59 I snipped off the three yellow (stator wires) from the MOSFET VRR and soldered on male 1/4"spade lug terminals. The three female spade lug terminals were removed from the KLR's VRR plug and plugged into the VRR connectors. Heat shrink boots were used to cover. Since it doesn't matter which stator wire goes to which diode, just connect them. The other VRR plug has two red (positive) and two black (negative/ground) wires. I simply use the supplied plug to adapt the KLR Black/Yellow (ground) to one of the VRR black wires and run a ground wire from the other VRR black terminal to the 6mm air box bolt near the VRR. This improves the bike's ground. The VRR White wire goes to one VRR Red wire and the other VRR red wire goes to the battery cable side of the starter relay. This reduces the voltage drop in the White Wire circuit by a bit. The lowerer (front) VRR mounting bolt goes through one VRR hole and a new mounting hole is made higher up/further back in the inner fender to mount the VRR. It still fits under the seat where there is good air flow while moving unless one has a sheep skin or such on the seat. I may move my VRR into the lower overflow tank area as have done on other bikes. What I haven't done and which makes me face palm is to connect the three yellow stator wires which are nearby rather than running wires from the VRR plug as in the past. I'm an idiot! I overlooked the stator wires which are right there in order to run the stator current to the back and then forward again. Face palm! Here's a comparison of the Suzuki MOSFET VRR with the stock KLR VRR: https://www.dropbox.com/s/itg7gzrr00ih71j/Suzuki%20MOSFET%20VRR%20%26%20KLR%20VRR%20Compared.jpg?dl=0 Another and more expensive option is to use a series type regulator such as an FH012 but since the KLR has no real stator issues (stator issues...can you say "Suzuki"?), I'm too cheap to spend the bigger bucks. My friend Mike is doing some looking for a series type but he's having some fun in trying to determine whether the "FH" VRR advertised here and there are actually series or shunt in disguise. Hoping he will post the outcome. It's simple to tell them apart from the circuit diagram or if on the bike but haven't a way to do it from the ads. Enough for now. I think I'll join our house rabbit in a nap.
------ Original Message ------ From: "mark ward" To: "DSN_KLR650@yahoogroups.com" DSN_KLR650@yahoogroups.com>; "Norm Keller" Sent: 2014-11-22 11:11:09 AM Subject: Re: [DSN_KLR650] Re: Electric output?

WELLLLLLL Norm Your looooooooong winded "speech". Taught me a few extra things, I didn't,......... even know to ask. I thing I love about my klr (07) is how easy it is to Bump Start, if, (WHEN, X-10. LOL) I live the key on while talking to someone etc etc etc etc. (deep breath) ETC. LOL Thanks Mark (W. Mich.) On Saturday, November 22, 2014 1:19 PM, "'Norm Keller' normkel32@... [DSN_KLR650]" DSN_KLR650@yahoogroups.com> wrote: The ignition is different as the Gen2 is coil & battery while Gen1 uses a dedicated charge coil in the stator for generating power for the CDI box. This is often referred as "magneto type" ignition because the ignition has its own separate system. In order to convert a Gen1 to a Gen2 stator, the ignition would have to be converted to some other power source or change the CDI box to one which can be powered from a "12 volt" DC system. IMO, this would be an undesirable conversion because the Gen1 has the ability to bump start and run without the "12 volt" system. It is much easier to bump start a Gen1 with dead battery, for example, because the Gen1 develops sufficient ignition charge power at quite low RPM. Gen2 with dead battery must turn the alternator at sufficient RPM to raise charging system (battery) voltage sufficiently to power the CDI to create a spark. The problem with this is that the battery's load, combined with that of lights and other components must be powered by sufficient alternator output. I have also been given to understand that the Gen2 must reach higher RPM than Gen1 in order to produce a trigger signal needed for the CDI to fire the coil. This will increase the difficulty in bump starting. Converting for some of us might include introducing a power converter in order power a Gen1 CDI from a "12 volt" system. For most people doing a conversion, converting to Gen2 stator would require replacing CDI box and (I think) ignition coil. The wiring also would require modification to accommodate wiring plugs and that the powering/stopping of the Gen1 and Gen2 ignitions require different strategies. IMO, one would be better to convert to an after market stator intended for Gen1. FWIW, one should also consider that there are at least two higher output aftermarket stators available. Anyone who has wound generating coils will appreciate that more output current will require larger diameter wire while more (higher) output voltage will require more turns of wire. While we are stuck with the standard voltage range, the principle that increasing the output Wattage, requires more wire in the stator. There isn't room to add much more wire so in order to increase output, larger wire is used. Unfortunately, this means that the alternator will reach sufficient voltage to begin charging at a higher RPM than before. If one consults the output graph of the higher output Gen1 stators, one will see that these are not a good choice for lower RPM riding such as trail work or stop and go city. Sorry to be long winded but wasn't certain of the context in which you asked the question so tried to cover bases.