| Author | Message | ||
     Nightsky |
Recently bought a salvage/rebuilt 2008 1125R. When I asked the seller about the electricals, he did mention bike has eaten two batteries already. When there's an entire section of a forum called "Stator/Voltage/Regulator/Charging System" you know something in this bike's electrical system is a disaster. I measured battery voltage of 12.75V at idle (1700 RPM on my bike.) No wonder batteries die on this bike. They're sulfating out. Should be minimum 13.8V, preferably higher. I imagine guys with bikes that idle at 1250 RPM spec really have battery problems. Well OK, one rides at high revs. Even at higher revs, 3000 RPM only produces 13.4V. Should be above 14V. When I measured AC current off a stator leg, I got 23.7 amps at 3k RPM. The headlights and ignition certainly aren't drawing roughly 450W. So this shunt regulator not only is not charging the battery properly, it's shorting the stator - but just enough to regulate to 13.4V at higher revs. It's a shunt regulator. That's what shunt regulators do. Measuring open stator voltage at 3k RPM reads 38 VAC (right at what the electrical manual says), but drops to 11.1 VRMS with vreg connected. A rough power calculation of stator dissipation at 3k RPM gives (38 - 11) * 23.7 * 1.5 = 960W total 3 phase power! So at only 3k RPM, the regulator is already dumping a kilowatt into the stator. No wonder pictures have brown burned windings. I read the 2009 stators are worse. I've looked around at the commercially available vregs for this bike, and they are all shunt regulators too! I think I'm going to design my own vreg and throw this one into the garbage. | ||
| Timebandit |
WELCOME & THANKS! Welcome to the forum, and Thank You, Nightsky, for buying a salvage bike and taking the effort to rebuild it and make it streetable again. I'm sure that everyone here appreciates seeing someone save a damaged bike from being parted out. I'll tip my hat to anyone who is willing to invest so much time and effort into keeping another 1125 on the road. | ||
| Dannybuell |
there are two brands of series regulators on the market that are being used in Buells. Compufire and Cycle Electrics. google search at top of this screen on those two companies for more discussions in that area. http://www.compufire.com/index.php?option=com_cont ent&view=category&layout=blog&id=2&Itemid=6 http://www.cycleelectricinc.com/RECTIFIER.html There was also a link to a kit with all the bits. I can't remember the name...... | ||
| Timebandit |
COMPUFIRE 55402 FWIW, I had thought about using the CompuFire 55402. One warning though -- some people have tried using it on the 1125 and have reported reliability problems. One guy had a sudden-death failure right after installing it on an 1125. Hearing this, I decided to do some due diligence before making the purchase. Here's what I found: Nobody had the Compufire product in-stock. I found a couple of on-line merchants who offered it on their sites, but they all said that the product was out-of-stock or backordered. When I read that the product was out of stock everywhere, that sent up a red flag. I decided to contact Compufire directly. I emailed Compufire and inquired about their 55402 product. The factory rep told me in his email that the 55402 was intended as a replacement for the H-D 32 amp products, and had the same footprint so it would bolt right on. It came with Packard WeatherPak terminals to mate with the Compufire 40 amp stator, and that I could change the terminals/connector to mate to my application. I was also told that although they marketed the 55402 as a 40A product, it was actually underrated and would handle 60A. I had heard the problems on this board about premature failure of the 55402 on the 1125, so I asked Compufire for additional information. I specifically mentioned that the 55402 was listed as "out of stock" or "backordered" at all of the on-line vendors, and I asked if it was in-stock and available for direct purchase from Compufire. I also asked if clipping the leads (as he recommended) would void the warranty. I also told him that my intent was to install the 55402 on a H-D product that had a 500W charging system. This information was enough for them to figure out that I was talking about an 1125. As soon as I asked for this information, the Compufire rep stopped responding to my emails. There have been anecdotal reports of sudden-death/infant mortality failures of the 55402 when used on the 1125, though some people seem to be using it on the 1125 without any problems. Word through the grapevine is that Compufire won't warranty the 55402 for our application. It worries me that the 55402 appears to be out of stock/unavailable from the on-line merchants, and that Compfire wouldn't answer my question about product availability, warranty after splicing wires, or my intent to use the product in an 1125 application. These are huge red flags that caused me to think twice about buying a Compufire product. The fact that they're not available, coupled with the reports of failures/no-warranty on an 1125 make me wonder if the product is unavailable because it needs to be re-designed. All of this gave me pause about considering the Compufire 55402 for my bike. I decided not to buy one. CYCLE ELECTRIC I also looked briefly at the CycleElectric products. I did not establish direct contact with the factory as I had done with Compufire, so I can't offer any first-hand information about them. Looking at the products, I was concerned that the footprint of the product wouldn't work for my application. They look like they're designed to mount on a pedestal that straddles the H-D front motor mount. I also wondered whether *ANY* vreg product designed for the lower charging system output on most Harleys would be adequate for 2009 1125 charging system. Unfortunately, it's really hard to get adequate tech specs for the products. This leaves me with a lot of doubt. All of this made me decide that rolling my own series regulator would result in a better result than buying either of the commercially available off the shelf products. When you roll your own, there's no guessing about the voltage / current / power dissipation of the internal components. | ||
| Nightsky |
Hi guys. Thanks for your welcome. And thanks for the links. I will check them out. Sometimes the engineer in me gets a little wrapped up in measurements. Can't help it. Being a former dirt biker, I don't have a broad exposure to a lot of street bikes yet, but the build quality of this Buell bike to me looks very high. The engineering also looks to be well thought out. This is why I bought it - well I did have some advice from a guy at work who had an XB. | ||
| Timebandit |
I'll try to help, for whatever my input is worth. 1. Measurements Your unloaded / open circuit stator voltages suggest that there's plenty of AC voltage coming out of the stator -- enough that a properly functioning Vreg should be able to produce adequate charging voltage -- but your DC voltages coming out of the Vreg really are just awful. Looking at your bike I'd want to know both the voltage and current measurements under a proper load condition, so that I could calculate real power output. I'm sure that you know that the kilowatt referenced in the open circuit application can't be an accurate number, as the loaded voltage output will probably drop from the open circuit voltage output when the system is put under load. I'm wondering how much the AC voltages will change when operating into a proper test load. For comparison, do you have AC voltages at 3K RPM with the shunt regulator attached? This measurement would represent the opposite extreme, a fully-loaded / maximal drain condition. Eye-balling things, it seems that in your case the Vreg is over-shunting, and dumping too much current to ground, causing the voltages to sag. What remains to be seen is whether your 2008 charging system is operating in-spec our out-of-spec. A proper load test would provide the answer. Are you still using the OEM (Ducati) regulator? That could be the problem. 2. Power Calcs. I see that you used a correction factor of 1.5 when doing the power calcs. Are you using a 3-phase power meter to take your power measurements, or are you clamping a single phase ammeter on a lead and correcting by sqrt(3)? | ||
| Timebandit |
3. Voltages. forgot to ask -- are those voltages you measured peak voltages or RMS voltages? Are they raw data from V/div on a 'scope, or did they come from an RMS meter? | ||
| Bextreme04 |
I replaced my VR with the FH0012 I got off ebay and my voltages stay around 14.3v all the time... no crazy variation or low charge at idle... never get a battery light anymore either and that's living in the desert where i can be sitting at a stop light in 100*+ weather with both fans running and HID headlights. ~3000 miles on it so far and no problems yet. I ended up switching to it because I was getting the system voltage message and all the lights would cut off from overvoltage. I have never heard of an undervoltage problem caused by the VR though, always seems to fail to an overvoltage condition. Might want to check all your grounds and see if you have the older 08 IC with the parasitic draw issues. | ||
| Bextreme04 |
oh BTW... 08 stators have a lower output and have not had the stator burning up issues. They went with a bigger output stator for 09-10 that burns out VR's and stators and so HD added a cut-out harness that disconnects one leg under certain conditions, unfortunately the higher output still kills VR's and stators even with the harness which is why you have all these threads about electrical issues.. in 09-10 bikes. Since you have an 08 It is unlikely to be the problem. | ||
| Bartimus |
2008 models had a problem with the instrument cluster, that drained the battery when they were parked. check your instrument, and see if you have the gear readout, i think this was the upgraded Instrument cluster. Old cluster = upgrade cluster new cluster = check your VR Hope this helps... | ||
| Sparky |
"I have never heard of an undervoltage problem caused by the VR." Well, I'm blaming my last stator replacement on the VR because the dealer replaced stator and VR. Dealer said the VR was defective (in some way). The indication was rapidly dropping voltage with check engine & battery icons lit. When I got home the stator showed less than 2 VAC on each leg. I'm fairly certain the stock VR eventually toasted my stator by shorting excess stator current to ground even though the upgrade harness/relay is installed. Those running a FH0012 with a stock '09 or '10 stator, I wish you guys all the good luck in the world because I'm led to believe it is a more efficient device for shorting the stator than the stock VR. But it's probably OK with an '08 stator which doesn't tend to overheat like the '09/'10s. | ||
| Timebandit |
I looked over Nightsky's numbers again. The amount of thermodynamic loss (heat generation) that goes into the 2008 charging system is truly astonishing. As he showed, the 2008 charging system is dumping almost a kilowatt of heat into the engine /stator at 3000 RPM. That's really bad. It's like having a hair dryer blowing heat into your engine at all times. The charging system wastes almost a kilowatt of engine output. A kilowatt equates to a parasitic loss of 1.34 HP. And that's only at 3000 RPM. As an example of the worst case scenario: Take the RPM up to 10,000 and the numbers get a LOT worse: If open circuit stator voltage scales up linearly as f(RPM) then the open stator voltage at 10k RPM would be: 38 VAC * 10,000/3,000 = 126.7 VAC. >> "So at only 3k RPM, the regulator is already dumping a kilowatt into the stator." A rough power calculation of stator dissipation at 10k RPM would be: (126.7 - 11) * 23.7 * 1.5 = 4113 W 4.113 KW * 1.34 HP/KW = 5.51 HP. This means that if the bike makes 146 HP, then you're wasting 5.51 HP, or 3.7% of the total engine HP on heat generation in the charging system. This suggests that while the 2008 charging system is capable of putting out about 300 watts, the actual amount of heat being dumped into the stator at 10k RPM, under the full load of a shunt regulator, to produce that 300W of power is going to be ~4 Kilowatts. That's a thermal efficiency of what, 7.29%? That's just awful. And that's for the 2008 stator, not the 2009 stator, whose numbers would be worse. This data predicts that with shunt regulation, it will be unavoidable that even the 2008 stators will suffer thermal failure given sufficient time, just like the 2009 stators are already failing. It's just that the 2008 stators haven't been in service long enough for the failures to manifest yet. This is the strongest argument I've heard yet for switching from a shunt regulator to a series regulator or a switching regulator. Better yet, it's a damned good argument for building a bike with an alternator. (Message edited by timebandit on November 16, 2011) | ||
| Nightsky |
Bartimus, it does help. I do have the gear readout, meaning I have a newer cluster. This is a salvage bike, and I think the original cluster was damaged. I read posts where people list their charging voltages all over the map. These factory installed vregs (Timebandit says Ducati) must have poor quality control. Mine simply outputs about 3/4 volt too low. The vreg isn't "broken", it just doesn't work right. Zener diodes are typically +-5%. To answer Timebandit's question, the stator is always under full load unless I disconnect it. My bike has a shunt reg. And I think my stator is OK. It passes the resistance and shorts tests, AC output is right level, and it does produce current. I have the electrical manual, and I'll think I'll reread the procedure for thoroughness. I don't like the Shindengen FH012. It's a shunt reg, meaning the stator will eventually fail from overheating. | ||
| Sparky |
I'm waiting (daydreaming actually) for somebody to figure out how to convert the excess waste current from the shunt regulator into something useful like forward propulsion. Thinking Toyota Hybridly, I mean if all the regulator is going to do is short out the stator, why not divert that energy to drive a motor (the rotor?) instead? Sorry for the threadjack. Going back in my box now. | ||
| Sprintst |
or a forward facing laser beam that would destroy any obstacle in your path?  | ||
| Timebandit |
>> (Timebandit says Ducati) Somewhere around here there are photos of the stock Vreg, which shows that the case says "Ducati E" on it. I looked, but couldn't find them. If you've got your Vreg out, take a look at it. I think that that "Ducati E" stamp belongs to Ducati Energia. Ducati Motor Holding is a different company that makes the motorcycles. Both of those companies are descended from the original company founded by the Ducati brothers. I would not be surprised if Ducati Motor Holding bought their Vregs from Ducati Energia. If that's the case, then worrying about the fact that these are two different companies amount to hairsplitting. | ||
| Timebandit |
>> "I'm waiting (daydreaming actually) for somebody to figure out how to convert the excess waste current from the shunt regulator into something useful like forward propulsion." That's not a threadjack! -- it's actually right on topic. The best way to convert the excess current from the shunt regulator into something useful like forward propulsion is to not waste the engine's power by generating that excess current in the first place! That current is generated by a shunt regulator that uses the bike's electrical system to suck useful power out of the engine and convert it into unwanted heat! It would be better to leave the power in the motor where you need it! By allowing the shunt regulator to create that wasted current you suffer an insane amount of power loss through conversion to unwanted heat. Better to not generate the wasted current in the first place, and to not convert it into unwanted heat in the engine. Better to leave the power in the engine as rotational power where it can be used for propulsion. Here's how you do that: ALTERNATOR. Get rid of the stator and replace it with an variable field alternator, which costs a little more in terms of weight and dollars, but is FAR more energy efficient and far more reliable over the long haul. - or - Keep the rotor/stator, but get rid of the shunt regulator and replace it with a switching regulator, which is FAR more energy efficient. With either solution, all of a sudden that 5.5 horsepower won't be totally wasted by sucking it out of the motor and converting it into 4+ KW of unwanted heat, which only heats your bike and taxes your cooling system. Instead you could keep that 5.5 HP for forward propulsion. Fixing the problems in the electrical system will be like a free power upgrade for the bikes. These are the reasons that almost all cars use alternators. It's also why BMW bikes use Bosch/VW alternators. The alternator is worth the additional weight and cost in terms of energy savings and enhanced reliability. The only reason that bikes come with rotors/stators is because manufacturers are trying to make their products lightweight, low mass and inexpensive. They can get away with this because people will accept reliability problems in their powersports toys that they would never accept in their cars. (Message edited by timebandit on November 16, 2011) | ||
| Nightsky |
This is SO FUNNY! Timebandit is right. The stock Buell vreg is a Ducati!  Does anybody think Italians are known for the quality of their electronics? Think Fiat. No wonder the output voltage of these stock regulators is all over the map. My regulator output is 13.4V. | ||
| Bextreme04 |
sparky - lol.. bottom line is I bought an upgraded regulator that is charging great and I have had no issues... all i keep reading on here is how people have upgraded to a series or switching regulator that has then burned out(compufire) or they have had a stator failure anyways. Maybe I missed something but haven't heard anyone complaining about failures on the FH0012  I ride mine at least 40 miles a day through town, usually below 5,000rpm and sometimes in 100*+ heat and have had zero issues once I updated the VR and the harness relay. Just my .02... results may vary | ||
| Reepicheep |
Timebandit, you have the right thoughts, but I don't think we have the original readings right. We know what the stock stator is rated for ( I think it is 400 or 500 watts, depending on year). The amount of engine power a shunt regulator wastes won't show up as anything but background noise even on a dyno, you would never feel the difference. One crank horsepower is 745 watts. The entire charging system takes less than one HP. (Message edited by reepicheep on November 17, 2011) | ||
| Timebandit |
> "Timebandit, you have the right thoughts, but I don't think we have the original readings right." Thanks for your insights. Which readings do you think are incorrect? I didn't take the readings, but Nightsky's test voltages look pretty accurate to me; they do match the factory test specs for the charging system. We also know that unloaded stator voltage does scale up linearly with RPM. Of course, take one look at the power output calculations and they are hard to believe, aren't they? > "One crank horsepower is 745 watts. The entire charging system takes less than one HP." On the surface, it's hard to accept the magnitude of the thermal cost of producing 400W or 500W of usable voltage output. Sure, the charging system output may only be 400W-500W (depending on the year), but that's the output number, not the input number. If a charging system electromotive efficiency is only 10%, then it really does cost 4KW on the input side to get 400W on the output side, and the other 90% of that 4KW is introduced to the system as heat. The bottom line is that an electrical charging system that's based on a rotor/stator instead of an alternator is thermally very inefficient. So much so that it is a recipe for disaster. | ||
| S21125r |
hmmm... interesting thought for those that street/strip. If (big if) the stock battery will last 10+ seconds with out stator input then maybe that extra 5 HP could be put to good use. Assuming you could rig up relays with a bar mounted toggle switch to turn the legs off once you stage. | ||
| Froggy |
There are people that race bikes that don't have charging systems at all, thats where the real gains are due to the reduction in weight and rotating mass. Quick disconnect connectors on a Lithium based battery means you can do a session on the track and then before your next one you swap it out and throw the old one on the charger. On a track bike, you don't have lights or fans, your only real power consumption is in the fuel injection system. | ||
| Reepicheep |
I talked to somebody that ran it on a dyno-jet with and without a charging system. No change in results. Efficiency would not come into it, as the efficiency loss is converting the gasoline into kinetic energy. If you "gain back" the power generation loss, you only gain back the part of it that is post gas-to-motion conversion. Which, as per the spec, is 400 or 500 watts. The original errors are, I think, two fold. First, I don't think the original measurement of power was right. It would need to measure both volts and amps simultaneously, and that's really hard. Secondly, I don't think whatever value you get at low RPM will scale linearly with higher RPM's. I think the magnetic field parts saturate, and the whole thing "tops out" and just holds there above a particular RPM (that I don't know where it is). Like I said though, at the end of the day, I talked to somebody who tried it on a dyno. 5 HP would have shown up, 1 HP would get lost in the noise. He saw nothing. | ||
| Sparky |
BX, I appreciate your inputs on the subject and your efforts to arrive at a suitable fix. I think we all need to learn from everybody's experience. My track record so far is 9000 miles: install upgrade harness/relay due to voltage spikes, 9200 mi: replace stator, 9800 replace VR, 14290 mi: replace stator & VR. So you can see I'm getting diminishing returns with the stock items. If the collective can try combinations of aftermarket parts that stay working for at least 10000 miles, then maybe we'll find the "right stuff". Thanks and keep us posted. | ||
| Easttroy |
Compufire isn't warrantying based on what? These bikes have a design that is in use throughout the motorcycle world, nothing that was done by buell is anything but a standard electrical design for a stator / regulator. Seems funny to me that the regulator dies if it is sized appropriately. | ||
| Nightsky |
We may not get anti-gravity if we recover that lost stator energy, but we can make the bike go faster! The numbers are real. I do electrical engineering for a living. I try to be careful. The shunt regulator clamps the stator to 11.1VAC on my 2008. The measured AC current through one stator leg was about 23 amps AC. Since 2 of the 3 stator windings share that leg, I must multiply by 1.5 to account for the current in the 3rd winding I'm not measuring. Disconnecting the vreg, my no load stator output was 38VAC at 3kRPM. At 4kRPM I measure 51.4VAC, so stator voltage is linear with RPM. Since the shunt reg always clamps stator output to 11 VAC, that (38 - 11) volt drop times 23 amps times 1.5 heats up the stator windings. Multiply it out to get 930W. Nearly 1kW is being dissipated in the stator windings at 3k RPM, even if you are only using maybe 150W of electrical output to run the bike. That is why these stators with shunt regs don't last without oil cooling. It's worse at higher RPMs. Anybody interested in seeing the measurement table? | ||
| Froggy |
Me  | ||
| Reepicheep |
Good info NightSky... There are two things that I think could confound an attempt to measure the actual power... 1) Non linear performance across RPM ranges (if, for example, the magnetic fields can only do so much, so they climb as expected versus RPM up to a point, then just level off). 2) Measuring current without disturbing voltage, and measuring voltage without disturbing current. If I was going to try and measure it, I would take the voltage out of the picture (at least input voltage). I'd run the stator output direct to a heavy extension cord with two or three monster 300 watt halogen shop lights on it (who's static resistance I know already), and sample the voltage across them at various RPM's. Which would be a lot of work, but would look TOTALLY cool rigged up in the garage! Then I'd use a simple V squared over R to calculate the power, and see where it maxes. With of course the RMS constant calculated... I'm guessing that wouldn't be the normal constant anymore (.606? I forget, been 25 years since my machines and power classes) because this isn't 60hz at 120V (though it is at least a sine wave). Actually, could that be the discrepancy between your calculated 930 watts and the factory claimed 500 - 600 watts? 930 * .606 is 560 watts or so. Or did you account for the RMS power elsewhere that I missed? (Message edited by reepicheep on November 18, 2011) | ||
| Reepicheep |
Dang. Now all I can think of is a loud Buell in a garage at night, and as the thing howls louder the lights glow brighter... |
