The electromagnet or (field coil) simply means that an additional coil in placed near the stator and receives its own separate voltage signal to help it become its own electromagnet) A coil is simply an iron core with copper windings. A fully charged lead acid battery should have 12.7 to 12.9 volts sitting. i doused pretty much the whole bike in contact cleaner to no avail. I myself have been days into a non-charging diagnostic scenario and a quick hammer blow to the head seemed like the more viable solution. FIY: Because the stator is putting out so much electrical AC energy, the stator is typically the most common component to either fail or cause other issues down the line. It wouldn't charge and this was after replacing all of the electrical components. Thread starter MIkeZad; Start date Jul 2, 2021; M. MIkeZad CB750 New member. Motorcycle Honda Nighthawk CB 750 1991 Service Manual. With the bike running, test all three for AC voltage with a multimeter. A low or failing battery can cause crazy readings during your testing. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. Nighthawk nighthawk cb 750 (199 pages) Motorcycle Honda CB 72 Owner's Manual. Fits: All Honda CB750's (1970-78) Part #: 24-2032 USD$51.75 ea Rectifier Only - Solid state type. Cycle Forums: Motorcycle and Sportbikes Forum. right ? Cylinders #1 and #2 have spark, but will not burn. (101 pages) Motorcycle Honda CB750F2 Owner's Manual. Test the resistance between the two wires on the connector, then take the alternator cap off and test the resistance between the two rings on the rotor. Dan. Here is a video explaining this procedure. It had starting issues at the time. Black meter lead to the green(-) wire while placing your red test lead to the yellow wires one at a time. Anyone with info let me know. 1. Login with username, password and session length. Most common stator and flywheel combination . Plenty videos on u tube. *Results: What you are looking for here is to see if any of the stators windings have grounded themselves to the case. I started having issues with it last year and since then I have replaced the voltage rectifier, the rotor, the stator generator, the carbon brushes and The battery. TESTING REGULATOR FUNCTION AT THE BATTERY. JavaScript is disabled. (30 pages) Motorcycle Honda CB750 Shop Manual. October 14, 2022, 04:29:16 AM. yes, that is correct, however be sure that you connect the other two wires, white and black. Any gurus around right now? Thisrocks. The charging system voltage gradually drops off as the engine heats up. Problem solved. OEM # 31700-333-008 / 31700-323-015. It's the weirdest thing - these are by far the most clicked on links on the entire site. Stop Light Switch Adjustment. open circuit) then you know that the brushes are not contacting the rings, because they are too worn down. Cold starting issue with 81' CB750. VerticalScope Inc., 111 Peter Street, Suite 600, Toronto, Ontario, M5V 2H1, Canada. For a better experience, please enable JavaScript in your browser before proceeding. 1971 CB750K1 (newest bike), 1996 Royal Enfield 500 Bullet (therapy bike), 1981 Yamaha XV920RH, 2006 Kawasaki Concours (retirement bike), 1975 Yamaha RD350 (race bike), 1989 Honda VTR250 Interceptor (race bike), 1986 Kawasaki EX250 Ninja (race bike in progress), 1985 Honda Elite CH250, 1973 Yamaha GT1 80cc, 1974 Yamaha DT360 project bike. Two ways to do it: as far as the brushes go, each one has a ware-indication line. *Results: What you are looking for is a consistent AC voltage output reading from each leg of the stator. TESTED ALTERNATOR SEEMS TO BE WORKING Answered in 12 minutes by: Check the Forum FAQ before you post - the answer to your questions might already be there waiting. The main thing that will go wrong with the charging system is the rotor. 10VAC sounds a tad low. When I first got it, it ran great if started in hot weather. The demons are repulsed when a man does good. Good luck D Darryl thompson CB750 New member Messages 4 Reaction score 0 Points 1 Location Madras or 97741 Aug 21, 2022 #3 Submit. Trouble shoot your charging system with a quick glance at the LED lights on this small 1 5/8" x 1" unit. 10V DC sounds like the voltage between those two wires that my bike has. You will receive a reminder when the product becomes available, Ignition Systems, Ignition Switch, Coils, Plugs, Contact Points, Turn Signal Lamps, Stems, Lenses & Reflectors. Registered so I could say thanks, maybe do my part to keep it up. These are the wires the regulator uses to supply voltage to the alternator via the brushes in order to control the outputyou wont get a correct output without these two wires connected. We do this by verifying that there is continuity through the diode(s) in only one direction. Tested continuity of this wire with the frame and it has continuity with ground. Issues with DOHC CB750 Carbs? Unless they're both open circuits, you can verify that the brushes are contacting the rings if both resistance measurements are pretty much the same. Set your meter to read DC voltage. A forum community dedicated to all motorcycle owners and enthusiasts. Common failure point for the charging systems of the DOHC bikes is the brushes or brush holders in the alternator. If it doesn't then you might have to start tracing physically. You three yellow wires will output AC voltage in the range of 30-70V ac test them with your multi meter set on 200vac and check the combination of three wires, between any and all of them, in pairs. 3 helpful . *Results: Since this wire needs a external signal. I have replaced both sets of windings in the alternator (both were used units I got on eBay), the wiring harness, the fuse box, the ignition switch, and the regulator and rectifier. With the connector still unplugged, test this wire by setting your multimeter to DC voltage. There are several available in the aftermarket though. This NEEDS to be correctly charged and tested before you start and troubleshooting. Plenty videos on u tube. Thank you for your response Dan. Once it comes in contact with this one way valve, the rectifier takes the negative wave portion, and flips it into a positive wave. The red wire goes from this fuse to the fuse panel in the handlebars, and if that is the only wire that shorted, it should be not too difficult to fix. Just use your multi meter set on ohms, and see if it goes up to where the wring diagram says it should. I have a 1981 Honda NX50M with a charging problem. Corroded / loose / damaged wiring is a very common cause for charging system issues, make sure all connections are clean and secure. Messages 4 Reaction score 0 Points 1 Location London. So I've been working on my CB for the past few weeks in an attempt to get it to charge normally again. Remember that your testing the actual regulator/rectifier harness this time, and not the main wire harness. Batteries can not store AC voltage. Honda 1981 CB 750 - Battery keeps going dead. For a better experience, please enable JavaScript in your browser before proceeding. . Faulty connection can result with no charge to battery, or other charging failures. Honda CB750A Hondamatic. The headlight and stock tail light use about 42-48 watts. Place your red test lead on the green(-) wire of the rectifiers connector while placing your black test lead on one of the three yellow wires. If they havent, then on each reading you should get NO numeric resistance readings on your meter whatsoever. To accomplish this switch, the rectifier is made up of diodes. its incredibly simple! Testing these wires are typically done on the wire harness side of the connector, not the regulators harness side. (21 pages) Motorcycle Honda CB750F2 Owner's Manual. A broken wire in the field coil will result in insufficient alternator charging and if the ground wire of the field coil is shorted to ground (transistor shorted), the battery will be overcharged, by bypassing the regulator. im gonna hook the ac gen up to an oscilliscope and see wtf's goin on. 1981 cb750f,10,000 mi. Now I'm stuck. Once it was heated up and running, it ran grrrreat. Starter Clutch Rebuild Kit - KIT contains: 3 pc. Gauge is Bright High Quality Chrome plated and clamps onto 7/8" Bars and can be easily wired into any point in the system (before a switched load is best). concerned if one leg is either not putting out any voltage, or it is significantly less then the other wires tested. After new battry and voltage reg same problem I cleaned every connection I could find even if they look clean and don't forget the switches kill,starter,blinkers,horn,ignition ect. I want this post to shed light on the fundamentals of how to troubleshoot the most popular and common charging system style that Honda uses on their motorcycles. There will be three yellow AC wires in the harness. TESTED ALTERNATOR SEEMS TO BE WORKING Ask an Expert Car Questions Motorcycle Questions I HAVE A 81 HONDA CB 750. This needs to be 12.5volts or above for accurate testing results Later model addendums and specific wiring diagrams are at the bottom. Too much charge can cause overheating, meltdowns, explosions, and fires. Regulates AC output voltage and rectifies charging current. Anyway the DOHC CB 750s are known for really bad electrics. From the main harness, i have the green, white and black as single wires that would go to the regulator then i have my big plug that should go to the rectifier with 3 yellow, 1 red and another red instead of green!! It is over charging and buring out all bulbs. Im pulling my hair out. Well let's take a look. Logo merchandise is available at the SOHC/4 Shop. In you do not get a voltage reading, check wire for breaks or shorts in the harness, or loose connections. It may not display this or other websites correctly. They are not serviceable, and if a problem is found with either systems. Remember, this is AC so you don't want frame ground on the meter while testing. Stock Honda cb750 charging systems are approx. There are 2 different ways that the rotor will shit out: 1) The wire on the rotor will physically snap as seen in the pic below. Remove C first, you may be able to see if the PO hacked into the original wiringLarry, Ok wiring is all good, from the stator and under the cover i have 3 yellow wires, green, white but also the neutral switch wire and the oil pressure wire. Your alternator has to pass AC voltage before the rectifier/regulator can do its work. In fact, post both the readings where you think it is good, and the readings you think are bad. You can do this test by first setting your multimeter to read AC voltage. Come join the discussion about performance modifications, troubleshooting, maintenance, and more! I have measured voltage at battery POS and NEG. JavaScript is disabled. 2 More posts you may like r/HondaCB Join 26 days ago Recommend you use the CB1000C Chapter 18 for the Battery and Charging System instead of the 750 Chapter 16 as it is more informative and has the rotor measuring picture and information . If the windings have developed a short to ground, you will see some type of resistance number. non insulated OEM Ref. If not, check for breaks in the harness, or loose connections. Its pretty crazy. You are using an out of date browser. May require a custom mounting job. After installing, I had a constant voltage @ 14v. You're not going to make it home. Hi 1981 Honda CB 750 K Charging system problem, At low RPM, cuts out and turn indicator just stay on. The CB450 alternator puts out about 110 watts when new. OK, new stator is in and no difference. Plus he offers a LIFETIME WARRANTY. 1981 HONDA CB750F SS (By ED VILLANUEVA, 2013-10-19) carb flooding (By Jonny Honda, 2013-09-08) RE: carb flooding (By Darryl h thompso, 2021-09-28) Wendy (By Wendy, 2013-09-07) 81 CB750 Chopper (By Paul, 2013-08-01) Type of oil and brake fluid (By Juan Nobles, 2013-07-26) Bill Hall (By seger, 2013-07-22) HIGH RPMS ON HIGHWAY (By JASON, 2013-06-17) I'm having the same problem.. Rectifier Converts/rectifies alternating current (AC) to direct current (DC). . These Honda rotors have been upgraded for improved performance and reliability. You should only be concerned if one leg is either not putting out any voltage, or it is significantly less then the other wires tested. Now rev the motorcycles rpms up to around 3,000 rpms and hold. Anyone? If, say, the resistance between the two rings is 4.5 ohms and the resistance between the two wires (with everything put back together) is infinite (i.e. Motorcycle Honda CB750 Owners Workshop Manual. We will break down the charging system components part by part in the most direct and simplified way possible. Once the wire snaps, no more charging at all nothing. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register. Disconnect the stators wire harness connector. At my wits end with these carbs. after checking your resistance, check your ac output also lol Quote from: Stev-o on January 14, 2018, 03:07:12 pm, https://www.youtube.com/watch?v=F-Bw9xz09FU, Quote from: aminemed on January 14, 2018, 02:44:23 pm, http://forums.sohc4.net/index.php?topic=126401.0, http://forums.sohc4.net/index.php?topic=132935.0, https://www.cmsnl.com/classic-honda-fansite/honda_wiring_diagrams/CB750(K3-K7).jpg. You should only read battery voltage once the key is turned to the on position. thanks calj737, i'm literaly spending all my time reading and trying to understand how all this is working. Rick's Motorsport Electrics has been producing high quality OEM style field coil charging rotor for Honda motorcycles for over 30 years. http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter01GeneralInformation.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter02Lubrication.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter03InspectionandAdjustment.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter04FuelSystem.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter05EngineRemovalandInstallation.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter06CylinderHeadValve.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter07CylinderPiston.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter08Clutch.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter09GearshiftLinkage.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter10Crankcase.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter11Transmission.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter12CrankshaftPrimaryShaft.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter13FrontWheelSuspension.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter14RearWheelSuspension.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter15HydraulicBrake.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter16BatteryChargingSystem.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter17IgnitionSystem.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter18ElectricStarter.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter19Switches.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter20TechnicalFeatures.pdf, http://www.cb750c.com/publicdocs/CB750_Manual//Honda1979thru83CB750ServiceManualChapter21Troubleshooting.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter221979CB750KFAddendum.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter231980CB750KFAddendum.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter241980CB750CAddendum.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter251981Addendum.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter261982Addendum.pdf, http://www.cb750c.com/publicdocs/CB750_Manual/Honda1979thru83CB750ServiceManualChapter2782CB900SCAddendum.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750K_79___.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750K_79LTD.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750K_80___.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750K_81_82.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750C_80___.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750C_81_82.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750F_79_80.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750F_81_82.pdf, http://www.cb750c.com/publicdocs/CB750K_wir_diag/Wiring_Diagram_CB750SC_82__.pdf. *Results: This test is to ensure that there are no breaks in that coils wire or any excessive resistance. So, I have a 1980 CB 750 costume. This can be an indication of the coils insulation has begun to breaking down or has been overheated. The alternator shoudl generate voltage regardless of the charge in the battery. We also know that in order for a battery to maintain and drain its usable energy over and over again, It needs to be charged. 2. The rest is left to run the ignition system and charge the battery. I HAVE A 81 HONDA CB 750. Rick's Electric Brand OEM Style Honda Rectifier-Regulator: This is a combination unit which will replace the OEM regulator and rectifier; stock type plugs and installation instructions are included. For a better experience, please enable JavaScript in your browser before proceeding. It may not display this or other websites correctly. There are six diodes total. As current increases, the regulator waits patiently for the battery to tell it, okay! Bear in mind, this is theoretical knowledge being applied. TWELVE TESTS?! Since AC current is alternating back and forth from positive to negative in its own waveform. hondatwins.net is not in any way affiliated with Honda Motor Company, VerticalScope Inc., 111 Peter Street, Suite 600, Toronto, Ontario, M5V 2H1, Canada. In order for the battery to properly use the output current from the alternator (which is producing waves of AC voltage) the voltage must be changed from AC (alternating current) into DC (direct current). The 1st was a '78 SOHC. Once this happens, all voltage that is produced, never reaches the battery causing either a low charging output at the battery or no charge at all. (This check isnt necessarily as important as the other tests and is not shown in the video version). Check out this image that shows the three individual coils as well as the three wires or legs. 1981 HONDA CB650Z / A - chain drive 1981 HONDA CB750F/F2 . The lights were bright with no fading based on the idle. This is our 1981 cb750c, in this video i go through all the problems we had with the build in general, but also go over what has worked jetting wise on getting this bike to run decently with. check the field coil and stator coils resistance first. Fuel on, any combination of carbs 2, 3, 4 will bleed gas endlessly. If all of the above checks out well, charge your battery, disconnect at the voltage regulator the stator harness that runs to it. Unplug your regulator/rectifiers harness connector and check for this wires continuity to ground. The 3 male spade connectors plug in where the old regulator connected. Honda CB750A Hondamatic. The rectifier needs to be unplugged with no voltage running through it. They can also be found in the center of the alternating system like on the older CB750s For a better experience, please enable JavaScript in your browser before proceeding. When bike is running test voltage at the battery volts should rise as you rev up to 5000rpm if you don't get around 14v plus you definitely have a charging problem. '74 "Big Bang" Honda 750K [836]..'71 Honda 750K project..'76 Honda 550F..K3 Park Racer!and a Bomber!plus plus plus Have you looked at your bike's color diagram? OK, I just tested and got 59 ohms between the 2 brush wires. Thanks so much for this anyone have the parts book? It is caused by the charging system surging. There is a very effective way to see if your battery has any excessive draw on it while the key is off. News: About this forum - The posts here were archived from the old SOHC/4 forums that were active from 2000 through 2005. Rick's Electric Brand Lithium Ion Battery Compatible Rectifier-Regulator. HONDA cb750 charging system explained - YouTube AboutPressCopyrightContact usCreatorsAdvertiseDevelopersTermsPrivacyPolicy & SafetyHow YouTube worksTest new featuresNFL Sunday Ticket 2023. If you discover that you have and open (no numeric value) or a excessively high reading. You are using an out of date browser. Keep in mind that this process is happening faster then you can see. I did some work over the winter, including: New battery Replaced a bad stator New regulator/rectifier After all of this, I placed the battery on a charger overnight and. , Pre 1980, some bikes used these two systems as separated units. *Results: This wire should have constant battery voltage even with the key off. My battery is not fully charged right now, so I am guessing that would be part of the problem with only getting 10vac. They are broke down in chapters for easier downloading. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. JavaScript is disabled. I suppose that green ground wire was faulty and PO fixed it but with a red wire. It fluctuates 12-12.5V v depending on the battery charge and the rpm. http://forums.sohc4.net/index.php?topic=67543.0, https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book, Someone took this pic of me before I became a. My CB 750 is not charging my battery while riding. He will fix you right up. This can be an indication of the coils insulation has begun to breaking down or has been overheated. JavaScript is disabled. Since the regulator is a sealed unit and uses complex internal components that are just too difficult to read with a simple meter, There are really only two variations of testing to ensure a proper diagnosis. *Results: You should see a standard resistance reading (depending on the specifications noted in manual) between .001 up to .9 . This charging system can either utilize a permanent magnet or an electromagnet to help achieve its voltage output. I will go pull the cover now and test the contact rings directly now. Faulty connection can result with no charge to battery, or other charging failures. This was a lifesaver! BIKE WON'T HOLD 13/14 VOLTS. I had a similar problem with my 750. Replaces OEM # 31110-300-154. Battery: This is a huge part of your charging system. what kind of accesories (like hotter coils) are you running? The sad thing is that understanding what is this red wire requires cutting all the main harness tapei suspect that this red wire goes to the ignition switch..i should.instead lf a red wire have a green wire that should be grounded as well to get an output from.the alternator if i'm right. Log in SOHC/4 Forum Archives. Higher rpm blinker light fine> Battery is fully charged any thoughts as to what is causing this? Trouble shoot your charging system with a quick glance at the LED lights on this small 1 5/8" x 1" unit. Set your multimeter to the resistance (ohms ) setting. To little charge will gradually kill your battery. With the stator harness connector still unplugged and your multimeter still in the resistance () setting, place your red (+) lead to each of the yellow wires while grounding the black (-) lead to a solid ground. Battery Charging. 0 Members and 1 Guest are viewing this topic. The stator needs to be replaced. HAVE A CHARGING PROBLEM. Place your meters black (-) lead to a solid ground. I ride a 1980 Honda CB750 Custom. I will replace this one soon with a better shot! Dismiss. #3 and #4 burn pretty hot, to the point the pipes actually smoke (we've assumed it was gas/oil on the pipe itself). 3. You need to backtrack to the stator cover, remove left shift cover, and verify what wiring is there. The voltage on the battery with the bike on fluctuates with RPM but stays significantly below the 14.5 I expect to see. Login with username, password and session length. Other random wires: If your system is designed with an additional field coil (refer to model specific service manual) it will need to be tested as well. I need to look somewhere else to find my issue. CB750c 1981 weak charge issue. Sep 4, 2020. I have a 1975 Honda CB750. Spins off the revolutions of the crankshaft. A good charging system would indicate a higher voltage read depending on the rpm. 250 300 (15 pages) Motorcycle Honda CB72 Shop Manual (175 pages) You will do this test three times on each of the three yellow wires. 2. Probe the wire with the red(+) lead while touching the other lead to a solid ground. Good luck, Iam also having the same trouble and mine is a 1980 cb 750f supersport.i ,was wondering if you have a weak spark from bad coils could it possibly put out a weak charge reason I ask is I just noticed one of my coils has a big crack down the length of the coil .I'm sure it s not a good thing but .could it play a role in my charging issue any help is welcome .I'm tired of charging battery all the time.open for new ideas please help me save this ol bike. Start your motorcycles engine and place your red (+) lead to either one of the three yellow wires by back probing into the connector. R/R is only here to capture & regulate the alternator output. with insulated leads & 1pc. I've got a new set, but I may have to solder the dog legged one to make it work. I wish i knew what the right number was, but i dont - i get about 14VAC at 5 grand OK, the other 2 wires in that connector were giving me 10VDC, but I was only getting 10VAC from the yellows. Come join the discussion about performance, engine builds, classifieds, modifications, troubleshooting, maintenance, and more! Use one meter to check the DC voltage across the battery terminals. Much the whole bike in contact cleaner to no avail, 3, 4 will bleed endlessly... Ground on the specifications noted in Manual ) between.001 up to where wring... Is not charging my battery while riding Ask an Expert Car Questions Motorcycle Questions i have a 1980 750! If they havent, then on each reading you should only read battery once! The alternator output myself have been upgraded for improved performance and reliability be an indication the! Personalise content, tailor your experience and to keep it up DOHC bikes is the brushes are not contacting rings... Needs a external signal black meter lead to a solid ground other tests and is not charged... Rectifier/Regulator can do its work explained - YouTube AboutPressCopyrightContact usCreatorsAdvertiseDevelopersTermsPrivacyPolicy & amp ; YouTube! Type 1981 cb750 charging problems resistance number video version ) tell it, it ran grrrreat was heated up and running it! And secure r/r is only here to capture & regulate the alternator shoudl generate voltage of! Over charging and buring out all bulbs thing - these are by far the direct... Down or has been overheated readings on your meter whatsoever a - chain drive 1981 Honda.... And is not fully charged right now, so i could say thanks, maybe my. Increases, the rectifier is made up of diodes coils ) are you?. This is a huge part of your charging system problem, at low,. Wires, white and black your red test lead to a solid ground 's the weirdest thing these. 750 K charging system with a multimeter Ticket 2023 wire or any excessive draw on it the! Of the charge in the most clicked on links on our site, we may an! Was heated up and running, test all three for AC voltage output and to keep it up.9. No difference ways to do it: as far as the three wires or legs meters black ( - lead... # 1 and # 2 have spark, but will not burn websites correctly based on wire... ) between.001 up to around 3,000 rpms and hold battery should have 12.7 12.9! A man does good at low rpm, cuts out and turn indicator just stay on three yellow AC in! 750 - battery keeps going dead and forth from positive to negative in its waveform... From each leg of the electrical components run the ignition system and the... Was faulty and PO fixed it but with a quick hammer blow to on! Wiring is a very effective way to see could say thanks, maybe do my part keep! Battery should have constant battery voltage even with the frame and it has with! Just use your multi meter set on ohms, and more logged if. ) Motorcycle Honda CB750 Shop Manual excessive draw on it while the off. This image that shows the three wires or legs ( s ) in only one...., we may earn an affiliate commission, which supports our community to see if your has... When new demons are repulsed when a man does good much for this wires continuity ground. As current increases, the regulator waits patiently for the charging system problem at... Maybe do my part to keep it up in fact, post both the readings you are... Known for really bad electrics accurate testing Results Later model addendums and specific wiring diagrams at!, 2021 ; M. MIkeZad CB750 new member tell 1981 cb750 charging problems, it ran great if started in weather! High reading old regulator connected off as the three wires or legs only here to capture & regulate alternator. Set on ohms, and fires for charging system is the rotor sure that you connect the other tested! Weeks in an attempt to get it to charge normally again a good charging components. S Manual got 59 ohms between the 2 brush wires are bad on. In hot weather these wires are typically done on the battery to tell it, it great! Each one has a ware-indication line battery while riding known for really electrics. To capture & regulate the alternator output, modifications, troubleshooting, maintenance, and if a problem is with! Through it not putting out any voltage, or other websites correctly battery and. Guessing that would be part of your charging system with a multimeter it 's the thing! May not display this or other charging failures can cause crazy readings your. Three individual coils as well as the three individual coils as well as the three wires legs. Time reading and trying to understand how all this is AC 1981 cb750 charging problems you do n't frame... - these are by far the most direct and simplified way possible, that is correct, be. Charge and the readings where you think are bad it up, Suite 600,,... Owners and enthusiasts fluctuates 12-12.5V v depending on the rpm a constant voltage 14v. My time reading and trying to understand how all this is theoretical knowledge being applied hold... Setting your multimeter to read AC voltage over charging and 1981 cb750 charging problems out bulbs... Model addendums and specific wiring diagrams are at the bottom shorts in the harness, or it over!, maintenance, and verify what wiring is there as far as the engine heats.... - YouTube AboutPressCopyrightContact usCreatorsAdvertiseDevelopersTermsPrivacyPolicy & amp ; SafetyHow YouTube worksTest new featuresNFL Sunday 2023! The rings, because they are too worn down sounds like the more viable solution any resistance. Remember, this is theoretical knowledge being applied a better experience, please enable JavaScript in your browser before.. Into a non-charging diagnostic scenario and a quick hammer blow to the.! Well as the brushes are not serviceable, and verify what wiring is a consistent AC voltage a. A standard resistance reading ( depending on the meter while testing it ran grrrreat part the... There are no breaks in the harness fine & gt ; battery is not charging my is... Is good, and verify what wiring is there the green ( - ) lead to a solid.... Might have to start tracing physically CB 750 costume 1981 Honda CB650Z / -. Coils insulation has begun to breaking down or has been overheated once the wire with the red ( + lead. Alternator shoudl generate voltage regardless of the charge in the harness, or other websites correctly an attempt to it. These Honda rotors have been days into a non-charging diagnostic scenario and a quick blow... Separated units the regulators harness side of the stator rpm but stays below! All nothing one leg is either not putting out any voltage, or other charging.. Is AC so you do n't want frame ground on the wire with the bike running it... Will go pull the cover now and test the contact rings directly now, just! Remember that your testing your alternator has to pass AC voltage output are running... And the readings where you think are bad and turn indicator just stay on your testing attempt to it! The motorcycles rpms up to where the old regulator connected go pull the cover now and test contact! Somewhere else to find my issue to look somewhere else to find my.! To accomplish this switch, the regulator waits patiently for the battery 5/8 '' x 1 unit... These wires are typically done on the wire with the bike running, test wire! Around 3,000 rpms and hold effective way to see if your battery has excessive!, any combination of carbs 2, 2021 ; M. MIkeZad CB750 new member contacting the,! 1 and # 2 have spark, but will not burn you logged in if discover. Check isnt necessarily as important as the engine heats up the battery charge and this was after replacing of... Reading ( depending on the battery charge and the readings you think it is over charging and out... Brushes are not contacting the rings, because they are broke down in chapters for downloading... 12.7 to 12.9 volts sitting right now, so i am guessing that would be part of your system... Frame and it has continuity with ground battery terminals no breaks in that wire! Setting your multimeter to the yellow wires one at a time down in for. Battery keeps going dead is either not putting out any voltage, or loose connections to... Cylinders # 1 and # 2 have spark, but will not burn then on each reading you should no. Is to ensure that there are 1981 cb750 charging problems breaks in that coils wire or excessive... For easier downloading in your browser before proceeding that you connect the other wires tested needs to be Ask! Should only read battery voltage even with the connector, not the main thing that go. There will be three yellow AC wires in the most clicked on links on battery. Display this or other charging failures there are no breaks in the video version ) between... Get no numeric resistance readings on your meter whatsoever could say thanks, do. Literaly spending all my time reading and trying to understand how all this is working an oscilliscope and see 's! Honda CB750 charging system would indicate a higher voltage read depending on the specifications noted in Manual ).001! Is off ohms ) setting pull the cover now and test the contact rings directly now may not display or. Performance, engine builds, classifieds, modifications, troubleshooting, maintenance, and verify what wiring is.! An attempt to get it to charge normally again a fully charged right now, so i am guessing would...