LaGrasta Posted July 13 Author Share Posted July 13 (edited) Finally checked the charging voltage, dead. The battery is 12.8 and only rises as I increase RPM to about 13v. New regulator needed? https://www.amazon.com/dp/B0BHQN17XV?psc=1&ref=ppx_yo2ov_dt_b_product_details Edited July 14 by LaGrasta Link to comment Share on other sites More sharing options...
docc Posted July 13 Share Posted July 13 EuroMotoElectrics? 1 1 Link to comment Share on other sites More sharing options...
Tomchri Posted July 13 Share Posted July 13 Roadstercycle.com Shindengen SH847. Works wonder for your electricial system. Cheers Tom. 4 1 Link to comment Share on other sites More sharing options...
gstallons Posted July 14 Share Posted July 14 Are these the guys that sell the hopped up voltage regulator ? Link to comment Share on other sites More sharing options...
LaGrasta Posted July 14 Author Share Posted July 14 I removed the rectifier, and checked the ohms, both directions. Negative bias 14.5, positive bias, no movement. If I understand correct, this is good. Just the same, I ordered a replacement, albeit an inexpensive one. At the very least, it will rule out the rectifier with certainty. Link to comment Share on other sites More sharing options...
gstallons Posted July 14 Share Posted July 14 Well , you tested a diode . There is more than that taking place in that little box . Get a new one just to test with . If it turns out good , I would buy the best (not most expensive) one available . 1 Link to comment Share on other sites More sharing options...
activpop Posted July 14 Share Posted July 14 On 7/13/2024 at 10:04 AM, LaGrasta said: Finally checked the charging voltage, dead. The battery is 12.8 and only rises as I increase RPM to about 13v. What should it be at increased rpm? Link to comment Share on other sites More sharing options...
gstallons Posted July 14 Share Posted July 14 (edited) It should be no more than 14v . I will have to go and start mine up ...at rest battery v was 12.4v , after start-up it was like 12.8v. Blip your throttle a few times like 3k or above , At 3k I got 14.5v . AGM batteries are different. Keep this in mind! You always want to blip your throttle or hold it steady above 2500 for a few seconds for the regulator to start working . TRUST ME . I worked on a BMW car for 3 days after I replaced the alternator and it still would NOT charge . For some stupid reason I blipped the throttle and it started charging. Edited July 14 by gstallons more info 2 1 Link to comment Share on other sites More sharing options...
LaGrasta Posted July 27 Author Share Posted July 27 (edited) Well, with the new rectifier, no change! I'm basically getting the same reading, 13.2 at idle and after throttle blips, or at steady higher rpm. Unless I'm mistaken, this now means it's my stator? Not to mention, my 30a fuse to 30a circuit breaker upgrade, is still melting! I'll research online how to test the stator while still installed, then possibly order another depending on results. I hope it's just a matter of removing the front cover to swap. Any advice guys? Edited July 27 by LaGrasta Link to comment Share on other sites More sharing options...
Tomchri Posted July 27 Share Posted July 27 Shindengen from Roadstercycle. Cheers Tom. Link to comment Share on other sites More sharing options...
Lucky Phil Posted July 28 Share Posted July 28 (edited) 7 hours ago, LaGrasta said: Well, with the new rectifier, no change! I'm basically getting the same reading, 13.2 at idle and after throttle blips, or at steady higher rpm. Unless I'm mistaken, this now means it's my stator? Not to mention, my 30a fuse to 30a circuit breaker upgrade, is still melting! I'll research online how to test the stator while still installed, then possibly order another depending on results. I hope it's just a matter of removing the front cover to swap. Any advice guys? 13.2 volts headlight on or headlight off? If it's with headlight off then check the voltage with headlight on. Here's some troubleshooting info from Brad Blacks site. It's for Ducati systems but the Guzzi is basically a Ducati single phase system. https://www.bikeboy.org/chargingsystemdiagnostic.html Phil Edited July 28 by Lucky Phil 1 Link to comment Share on other sites More sharing options...
gstallons Posted July 28 Share Posted July 28 Now , I am not smart enuf to look up history on this forum . I did Google "testing the charging system on a Moto Guzzi V11 Lemans" and got lots of hits and the all referred to this forum . Most conversations go WAY back and are interesting for sure . Docc , Roy and others were already at the head of the class on this subject. Two critical points are 1 make sure you are using a GOOD and fully charged battery. 2 make sure you have a ground wire running from the regulator to a close bolt on the engine block. Use shakeproof washers on both sides of the terminal on a clean surface along with a non-melting grease .Do not go from the regulator to the battery neg. terminal . If the factory neg. wiring in the harness fails w/this in place you will have troubles and I mean TROUBLES . Remember , these charging systems are rinky-dink and just recharge the battery , they are not an electrical generating station . Treat them as such . If you are pretty smart on 12 DC ( I know an alternator puts out AC voltage) electrical systems read the post Phil posted above 3 or 4 times to appreciate all the info in the article. You will spend a good amount of time learnin' about what you need to know for in the future. Good Luck 1 Link to comment Share on other sites More sharing options...
gstallons Posted July 29 Share Posted July 29 You will enjoy being able to know something for sure and look at a wiring diagram and know if it's upside down or not ! Link to comment Share on other sites More sharing options...
LaGrasta Posted August 7 Author Share Posted August 7 (edited) Well, my Amazon Chinese replacement rectifier did not fix my situation. $40 shot as it's no returns. I wasn't convinced this new one was bad, but the test results displayed were identical. I had a knowledgeable friend look it over today and he thinks it's the rectifier. If it truly is a junk part, I'll eat the cost and buy a better one. However if I buy another, and it doesn't fix the problem, I'll be so disappointed. The charging system is simple enough, so my question is, might it be something else I'm missing or is it indeed still the rectifier needing replaced (relay issue)? headlight works low and high, as well as the brake light. I should mention, if the battery is disconnected, the bike stops running. The more expensive rectifiers I'm considering is these: https://www.regulatorrectifier.com/products/1998-2004-moto-guzzi-v11-sport-lemans-regulator-rectifier https://roadstercycle.com/index.htm https://www.mgcycle.com/index.php?main_page=product_info&cPath=37_161&products_id=1277 I'm leaning toward this one, as they are based a few miles from my home. https://www.electrosport.com/products/esr515-regulator-rectifier-ducati-1-phase-charge-light-output Advice, direction? Edited August 7 by LaGrasta Link to comment Share on other sites More sharing options...
Tomchri Posted August 7 Share Posted August 7 If your keeping the bike, very happy with # 2. Have installed 4 from Roadstercycle, perfect charging. Cheers Tom. 1 Link to comment Share on other sites More sharing options...
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