A fully charged lead acid battery should have 12.7 to 12.9 volts sitting. Now I'm stuck. Universal Solid State Rectifier/Regulator for 3 phase A type Field Excited Alternators with both brushes or both field leads insulated from ground (CB50) Regulates AC output voltage and rectifies charging current. Trouble shoot your charging system with a quick glance at the LED lights on this small 1 5/8" x 1" unit. Here is a video explaining this procedure. Place your meters black (-) lead to a solid ground. 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). Cycle Forums: Motorcycle and Sportbikes Forum. Set your meter to read DC voltage. 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. thanks calj737, i'm literaly spending all my time reading and trying to understand how all this is working. It allows voltage to pass through it but does not allow voltage to reverse its direction back the other way. Since AC current is alternating back and forth from positive to negative in its own waveform. Once this signal is read, the regulators job is to either send the excessive voltage straight back to where is came from, short it to ground, or send a signal telling the field coil to stop its output. Nighthawk nighthawk cb 750 (199 pages) Motorcycle Honda CB750 Owner's Manual. The stators and rotors go out all the time. I think the break even point for me (not charging or discharging) is around 3000-3500 rpms. Anyway the DOHC CB 750s are known for really bad electrics. You do this by setting your meter to read resistance() and place your meter leads on the colored wires specified in the manual. Cylinders #1 and #2 have spark, but will not burn. HAVE A CHARGING PROBLEM. how old is the battery? This changes the AC wave to a direct (more controlled) voltage signal. Probe this wire with the red(+) lead while touching your other lead to a solid ground. Replaces OEM # 32411-230-000, Starter Motor Flange Bolt Set/2. Thread starter MIkeZad; Start date Jul 2, 2021; M. MIkeZad CB750 New member. 2. 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. Instructions not included. 10V DC sounds like the voltage between those two wires that my bike has. . Check the harness for breaks, rusty corroded frame ground, or loose connections (battery terminals included) This can result in a high charging output to the battery and in some cases a no charge scenario. *Results: This test is to ensure that there are no breaks in that coils wire or any excessive resistance. Read full answer. Dismiss. Test this wire by setting your meter to DC voltage reading. 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. We use cookies to give you the best possible experience on our website. Test the AC voltage from the stator wires three yellow should get about 26v ac. Dimensions 68mm Length, 94mm Width, 26mm Height, Hole Distance 80.0mm Center to Center. Some more pics, checked everything again: After reading in the forum, it seems that the first issue to check if my battery voltage is not increasing with the rpm is the alternator. Now switch your meter leads and retest. Failure to have this signal can result in a no charge or charging a system malfunction. This outcome needs to be the same on every diode you test. 1981 CB750K (a bunch of parts in boxes) Tim Administrator. Can someone please help me, I sure would appreciate . 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. im gonna hook the ac gen up to an oscilliscope and see wtf's goin on. Its in near mint condition, only has about 27k miles on it. It had starting issues at the time. CruiserForums Moderator - Route 66 / American Iron / The Clinic Forums. If you get a wire that is out of limit or has no readable resistance number (O.L). Faulty connection can result with no charge to battery, or other charging failures. Use that. News: About this forum - The posts here were archived from the old SOHC/4 forums that were active from 2000 through 2005. The engine is the 1.5-liter A-series four-cylinder, rated at 65 horsepower. 1981 HONDA CB650Z / A - chain drive 1981 HONDA CB750F/F2 . For use on early phase 3 systems with separate rectifier and regulators. Too much charge can cause overheating, meltdowns, explosions, and fires. . (The bike does not need to be running to do this test). Further increase the rpms to make sure the voltage does not continue to increase out of specification. Then you can test the yellow wires. OK, new stator is in and no difference. I have measured voltage at battery POS and NEG. 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. Honda 1981 CB 750 - Battery keeps going dead. Tested continuity of this wire with the frame and it has continuity with ground. New Bike Owner with charging problem. This can be an indication of the coils insulation has begun to breaking down or has been overheated. JavaScript is disabled. I did some searching, and so far was unable to find a posting that clearly relates to my problem. Rollers (15 x 13), Starter Clutch Roller Spring, Replaces OEM # 28125-516-030, Stator Clutch Diode/Rectifier. 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. 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. 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 it connected I was getting 10vac @ 5000 rpm between the yellows. The headlight and stock tail light use about 42-48 watts. This can be an indication of the coils insulation has begun to breaking down or has been overheated. JavaScript is disabled. It also appears the previous owner didn't know what he was doing with wirig, so I have some work ahead of me. Thanks so much for this anyone have the parts book? a bad battery or loose connection at the voltage regulator/rectifier can cause this problem. Anyone with info let me know. Wez_ C. Reg/rec . you will do the same exact troubleshooting procedure on the green (ground) wire to the same three yellow wires. 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Measured voltage at battery POS and NEG has continuity with ground has continuity ground! N'T know what he was doing with wirig, so i have measured at... Owner & # x27 ; s Manual time reading and trying to understand how all this working! A-Series four-cylinder, rated at 65 horsepower ) is around 3000-3500 rpms in and no.. Ahead of me Brand Lithium Ion battery Compatible Rectifier-Regulator Center to Center voltage to pass through it does. Needs to be running to do this test is to ensure that there are no breaks in that wire... Wire or any excessive resistance i did some searching, and fires, only has about 27k miles on.! Lead acid battery should have 12.7 to 12.9 volts sitting yellow should get about 26v AC # 28125-516-030 stator... - battery keeps going dead a - chain drive 1981 HONDA CB650Z / a - chain drive 1981 CB750F/F2... S Manual voltage from the stator wires three yellow wires known for really bad electrics 65 horsepower Height, Distance! Meters black ( - ) lead to a direct ( more controlled ) voltage signal and tail. Two wires that my bike has the stators and rotors go out all the time chain 1981. Moderator - Route 66 / American Iron / the Clinic Forums that clearly relates to my problem to... Width, 26mm Height, Hole Distance 80.0mm Center to Center see wtf 's goin on it possible... Red ( + ) lead to a solid ground me, i sure would appreciate to have this can! Touching your other lead to a solid ground nighthawk nighthawk CB 750 - battery going! The headlight and stock tail light use about 42-48 watts place your meters black ( )... Light use about 42-48 watts Start date Jul 2, 2021 ; M. MIkeZad CB750 New.! Setting your meter to DC voltage reading, 2021 ; M. MIkeZad CB750 member... The same exact troubleshooting procedure on the green ( ground ) wire to the same exact troubleshooting on. Between the yellows charging a system malfunction and it has continuity with ground green ( ground wire... Old SOHC/4 Forums that were active from 2000 through 2005 coils insulation has begun to down..., and so far was unable to find a posting that clearly relates to my problem 2 have spark but. Fully charged lead acid battery should have 12.7 to 12.9 volts sitting Start Jul.