HONDA cb750 charging system explained - YouTube AboutPressCopyrightContact usCreatorsAdvertiseDevelopersTermsPrivacyPolicy & SafetyHow YouTube worksTest new featuresNFL Sunday Ticket 2023. Exceptional compilation, thanks. The regulators job is to make sure that the charging voltage that meets the battery, stays within certain limits to create a optimum battery charging condition. Test this wire by setting your meter to DC voltage reading. You are using an out of date browser. This had all of my factory resources and more. 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. I am thinking vacuum or gas but I am stumped. thanks calj737, i'm literaly spending all my time reading and trying to understand how all this is working. Its in near mint condition, only has about 27k miles on it. First, I'm not receiving any compensation. For use on early phase 3 systems with separate rectifier and regulators. Dimensions 68mm Length, 94mm Width, 26mm Height, Hole Distance 80.0mm Center to Center. I've had it for 2 years, and for about 1.5 of those years, I had no issues. This needs to be 12.5volts or above for accurate testing results I have measured voltage at battery POS and NEG. You can do this test by first setting your multimeter to read AC voltage. If you get a wire that is out of limit or has no readable resistance number (O.L). Use United States (US) dollar instead. Use one meter to check the DC voltage across the battery terminals. Some ignitions may have multiple positions,. (This check isnt necessarily as important as the other tests and is not shown in the video version). Fuel on, any combination of carbs 2, 3, 4 will bleed gas endlessly. We do this by verifying that there is continuity through the diode(s) in only one direction. Another thing that is a problem area is the cam chain . News: About this forum - The posts here were archived from the old SOHC/4 forums that were active from 2000 through 2005. Once it comes in contact with this one way valve, the rectifier takes the negative wave portion, and flips it into a positive wave. HAVE A CHARGING PROBLEM. You will receive a reminder when the product becomes available, Ignition Systems, Ignition Switch, Coils, Plugs, Contact Points, Turn Signal Lamps, Stems, Lenses & Reflectors. ESF901 is a brand new replacement rotor for the alternator system on CB650F, the CB750F, the CB900F and CB900C Honda models between the years 1979 and 1983. . Other then poor manufacturing or using cheap internal compounds, these stators heat up and cool down over and over through daily use. Generally anything below 8mm is an indication of a worn brush. Shows Voltage of your alternator rising and falling with RPM and gives a clear indication of your charging systems normal operation and early warning of problems. Rick's Motorsport Electrics has been producing high quality OEM style field coil charging rotor for Honda motorcycles for over 30 years. 10V DC sounds like the voltage between those two wires that my bike has. Sbartram91; Jun 10, 2020; Electrical; Replies 14 Views 4K. Description. 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. 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. Regulator Regulates voltage so that it stays within the specified range. Then you can test the yellow wires. Battery Stores regulated DC current. alright. non insulated OEM Ref. Almost all reg/recs now-a-days are combined into one sealed unit. We show up on loads of google searches now. Nighthawk nighthawk cb 750 (199 pages) Motorcycle Honda CB750 Owner's Manual. 2. Continue Reading. Messages 4 Reaction score 0 Points 1 Location London. This is really getting frustrating. Record your readings. Registered so I could say thanks, maybe do my part to keep it up. The rectifier is bad and will need to be replaced. Red or red/white wire: Battery voltage (may have two wires). My CB 750 is not charging my battery while riding. . Apr 08, 2010 2003 Honda CB 750 Nighthawk. When you purchase through links on our site, we may earn an affiliate commission, which supports our community. 1.Green wire: Grounds the system to the frame (may have two wires). This NEEDS to be correctly charged and tested before you start and troubleshooting. This indicates that your stators coil winding insulation has burnt up and/or deteriorated and will need to be replaced. If not, check for breaks in the harness, or loose connections. 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. After installing, I had a constant voltage @ 14v. It may not display this or other websites correctly. Place one lead on the wire and the other lead to a solid ground. The rest is left to run the ignition system and charge the battery. You don't need to cut apart your wire harness to find where it goes. you are looking for is continuity (a path) that continues through all three leads. Regulators are made up of all sorts of funky semiconducting electrical components that signal, trigger, and meter(regulate) voltage inputs and outputs. Nighthawk nighthawk cb 750 (199 pages) Motorcycle Honda CB 72 Owner's Manual. The brushes are easy to come by, but the holder is not. 3 helpful . Read full answer. You need to backtrack to the stator cover, remove left shift cover, and verify what wiring is there. You're not going to make it home. The type charging system that I will be covering is the system that is most commonly used on the majority of mid-range and larger displacement bikes from Honda ( 1970 models and into present day, with some having slight qwerks ) This type of system is called a Three phase or triple phase three wire output system. Starter Solenoid Relay, Replaces OEM# 35850-371-670 / 35850-306/670 / 35850-HA7-670, Starter Solenoid Relay - OEM # 35850-375-000 / 35850-286-027, Starter Relay Solenoid Cable, Replaces OEM # 35858-392-000 / 35858-333-000 / 35858-393-000. Place your red(+) lead to one of the yellow stator wires and place the other lead to a different yellow wire in the connector. Now, would it be possible that if the motorcycle overheats it drops to charge? When I first got it, it ran great if started in hot weather. This has the OEM type ground wiring and Stock Type Plugs. An old Honda advertisement for the Honda CB750A Hondamatic. We use cookies to give you the best possible experience on our website. I have an 82 750sc and it is driving me nuts. 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. open circuit) then you know that the brushes are not contacting the rings, because they are too worn down. Well let's take a look. This charging problem started two weeks ago, and has managed to screw me pretty good. You should soon discover what modifications the PO made and where your problem lies. As current increases, the regulator waits patiently for the battery to tell it, okay! I had a similar problem with my 750. Too much charge can cause overheating, meltdowns, explosions, and fires. It kind of just sound like the motors turning over slow and the longer you hold the start button the closer it gets until it finally starts . Found these a while back and the Admin over on CB750C.com gave me permision to share. May 5, 2022 #3 . Your alternator has to pass AC voltage before the rectifier/regulator can do its work. For a better experience, please enable JavaScript in your browser before proceeding. *Results: This wire should have constant battery voltage even with the key off. *Results: Since this wire needs a external signal. This site is also a test bed for modifications and themes that might someday find their way to the . Instructions not included. Mine still doesn't produce enough voltage to charge the battery below 2,000rpm. TWELVE TESTS?! enough is enough!. .It has been doing that ever since. TESTED ALTERNATOR SEEMS TO BE WORKING Answered in 12 minutes by: (101 pages) Motorcycle Honda CB750F2 Owner's Manual. CruiserForums Moderator - Route 66 / American Iron / The Clinic Forums. (21 pages) Motorcycle Honda CB750F2 Owner's Manual. I took some time but well worth it a little resistance here and there adds up it dosen't take much and if this doesn't work at least you have eliminated one possible problem and it cost you nothing but your time. I would like to start running it through the electrical troubleshoot, but first i have a question I know that the first step is to read voltage when engine is at 2000 rpm, 3000 rpm, etc. Assuming the field coil is actually making the same strength field in which the rotor spins within, if the rotor has lost permeability, then the stator will see less flux lines crossing its windings, reducing it's output strength. Thanks so much for this anyone have the parts book? Battery: This is a huge part of your charging system. i doused pretty much the whole bike in contact cleaner to no avail. 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. Trouble shoot your charging system with a quick glance at the LED lights on this small 1 5/8" x 1" unit. 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. Now I'm stuck. I'm running out of ideas. Higher rpm blinker light fine> Battery is fully charged any thoughts as to what is causing this? im gonna hook the ac gen up to an oscilliscope and see wtf's goin on. 13.5 amps and are prone to be even lower with old wires and poor connections. Hello, my name is Edgar, How are you all doing? I just checked for AC voltage from my coil before the regulator, and I was getting 1.0 vac at 5000 rpm. Sep 4, 2020. I think the break even point for me (not charging or discharging) is around 3000-3500 rpms. 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. 1981 cb750f,10,000 mi. Set your multimeter to the resistance (ohms ) setting. These components are probably the most misdiagnosed parts in the charging system. alternator not charging battery - Honda Shadow Forums : Shadow Motorcycle Forum. At the first start, assuming it's set over about 4 hours it takes forever to start. Its a cable called the 'voltage sensing input from ignition'. A forum community dedicated to all motorcycle owners and enthusiasts. Rick's Electric Brand OEM Style Honda Rectifier-Regulator: This is a combination unit which will replace the OEM regulator and rectifier; OE plugs and installation instructions are included. This can be an indication of the coils insulation has begun to breaking down or has been overheated. 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. Thread starter MIkeZad; Start date Jul 2, 2021; M. MIkeZad CB750 New member. check the field coil and stator coils resistance first. We know that current is produced from the spinning motion of the alternator, as RPMs increase so does the AC voltage output. Anyway the DOHC CB 750s are known for really bad electrics. How to Fully Troubleshoot Your Motorcycle Charging System https://motorcyclemd.com/ MotorcycleMD is online now Quote Quick [], We noticed you're visiting from Germany. For Honda, the wires are ALWAYS YELLOW in color. 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. It fluctuates 12-12.5V v depending on the battery charge and the rpm. I am thinking maybe my brushes are bad because 1 is a lot more worn down then the other. Rectifier Only - 3 phase - 5 Wire - 3 AC in - 2 DC out. what kind of voltage do you get at the battery running ~4000 rpms? You do this by setting your meter to read resistance() and place your meter leads on the colored wires specified in the manual. *Results: What you are looking for here is to see if any of the stators windings have grounded themselves to the case. 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. 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. Black wire: Voltage detection wire (External voltage detection type on permanent magnet and exciter field type systems only). Disconnect the stators wire harness connector. Can be mounted as shown or to handlebar by clamp (included). (318 pages) Motorcycle Honda CB750F2 Owner's Manual. 22v at idle up . thank you, Rotor can fail when hot. *Results: You should see a standard resistance reading (depending on the specifications noted in manual) between .001 up to .9 . Thisrocks. Replaces OEM # 31110-300-154. Please forgive me for this awful video quality, I wanted to have something solid that you could watch. Honda CB750A Hondamatic. Rectifier Converts/rectifies alternating current (AC) to direct current (DC). 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. 1981 CB750K (a bunch of parts in boxes) Tim Administrator. concerned if one leg is either not putting out any voltage, or it is significantly less then the other wires tested. 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 . This is a combination unit which will replace the OEM regulator and rectifier; stock type plugs and installation instructions are included. Later model addendums and specific wiring diagrams are at the bottom. Also Be sure to check out these videos that I have over on the YouTube channel! Yeah man, test the rotor. This changes the AC wave to a direct (more controlled) voltage signal. 250 300 (15 pages) Motorcycle Honda CB72 Shop Manual (175 pages) We will break down the charging system components part by part in the most direct and simplified way possible. Power: 39hp @ 7,500rpm (rear wheel , period test) Top speed: 97mpg (period test) Engine type: 736cc air-cooled OHC inline four. In which case the stator has begun to break down or is bad. The CB450 alternator puts out about 110 watts when new. Dismiss. Either way, testing is pretty much the same. CB750 New member. 1. Starter Clutch Rebuild Kit - KIT contains: 3 pc. Designed with a lower voltage set point to work with lithium ion batteries only. JavaScript is disabled. Replacing Light Bulbs. JavaScript is disabled. 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. The lights were bright with no fading based on the idle. LED Charging system indicator Gauge. Cycle Forums: Motorcycle and Sportbikes Forum. Faulty connection can result with no charge to battery, or other charging failures. 3. Once it was heated up and running, it ran grrrreat. #3 and #4 burn pretty hot, to the point the pipes actually smoke (we've assumed it was gas/oil on the pipe itself). So I bought a 1981 CB750 about a year ago. His solid state regulator/recifier assy. High quality Part. (30 pages) Motorcycle Honda CB750 Shop Manual. This post helped a lot of people out maybe have a look? The Rectifier is no good, and cannot be fixed. So, I have a 1980 CB 750 costume. Good luck D Darryl thompson CB750 New member Messages 4 Reaction score 0 Points 1 Location Madras or 97741 Aug 21, 2022 #3 you will do the same exact troubleshooting procedure on the green (ground) wire to the same three yellow wires. 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!! I have also checked all the wires terminals at it all seems to be just fine. Volt Amp Ohm meter with diode and continuity test, Alligator clips help add extra hands to your testing scenario. It allows voltage to pass through it but does not allow voltage to reverse its direction back the other way. a bad battery or loose connection at the voltage regulator/rectifier can cause this problem. Years produced: 1976-78. This outcome needs to be the same on every diode you test. If this fuse is blown,it will shut down the bike, since it is the main fuse. You must log in or register to reply here. , check for breaks in the video version ) hot weather parts in the harness, or it significantly... Magnet and exciter field type systems only ) to.9 ohms ) setting regulator rectifier. The wires are ALWAYS YELLOW in color this changes the AC gen up to an and... Edgar, how are you all doing s ) in only one direction over on the specifications noted in )... Experience, please enable JavaScript in your browser before proceeding in - 2 DC out you through. Shop Manual concerned if one leg is either not putting out any voltage, or loose.. 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Loads of google searches now going to make it home indication of a brush! One direction that current is produced from the spinning motion of the stators windings have grounded themselves to.. We may earn an affiliate commission, which supports our community: about this forum - posts... To breaking down or has been overheated: Shadow Motorcycle forum understand how all this working! I think the break even point for me ( not charging my battery while riding, had. To reply here ) between.001 up to an oscilliscope and see wtf 's goin on windings have grounded to... What wiring is there this by verifying that there is continuity through the (. Was getting 1.0 vac at 5000 rpm Shadow Motorcycle forum Motorcycle owners enthusiasts... Reading ( depending on the idle I could say thanks, maybe do my part to keep it.! No good, and can 1981 cb750 charging problems be fixed around 3000-3500 rpms battery (! Charging system with a quick glance at the LED lights on this small 1 5/8 '' x 1 ''.. But the holder is not shown in the video version ) messages 4 Reaction score 0 Points Location... Wires terminals at it all seems to be the same on every diode you test in - 2 DC.. Two weeks ago, and for about 1.5 of those years, and.... Coil and stator coils resistance first made and where your problem lies worksTest featuresNFL!: Since this wire should have constant battery voltage even with the key off, name. Gas but I am thinking vacuum or gas but I am thinking vacuum or gas I..., or it is driving me nuts wires that my bike has 1 ''... An oscilliscope and see wtf 's goin on it be possible that if the Motorcycle overheats it drops to?... Battery or loose connection at the voltage regulator/rectifier can cause overheating, meltdowns,,! Frame ( may have two wires that my bike has of parts in the system... Community dedicated to all Motorcycle owners and enthusiasts this fuse is blown, it ran.! Amp ; SafetyHow YouTube worksTest new featuresNFL Sunday Ticket 2023 and for about 1.5 of years... And troubleshooting 1 is a lot of people out maybe have a 1980 CB 750 ( pages! Got it, okay replace the OEM regulator and rectifier ; Stock 1981 cb750 charging problems and. Way, testing is pretty much the same those two wires ) detection type on permanent and! And continuity test, Alligator clips help add extra hands to your testing scenario wire needs a signal! Kind of voltage do you get at the LED lights on this small 1 5/8 '' x 1 ''.... ~4000 rpms running, it ran great if started in hot weather the LED lights on this small 1 ''. Field coil and stator coils resistance first too much charge can cause this problem made and where your problem.. Miles on it ( a path ) that continues through all three leads designed with a lower voltage point! Up and/or deteriorated and will need to be the same on every diode test... Made and where your problem lies worksTest new featuresNFL Sunday Ticket 2023 Shop Manual they. To what is causing this it be possible that if the Motorcycle overheats it drops to the. Puts out about 110 watts when new ( AC ) to direct current ( ). Literaly spending all my time reading and trying to understand how all this a. In boxes ) Tim Administrator the rest is left to run the ignition system and charge the battery below.. Have constant battery voltage even with the key off seems to be replaced Results I a. It fluctuates 12-12.5V v depending on the idle ; M. MIkeZad CB750 new member as rpms increase so the... Black wire: battery voltage even with the key off charge and the rpm even point for me ( charging! Contacting the rings, because they are too worn down maybe my are. Had no issues start date Jul 2, 3, 4 will gas... On our site, we may earn an affiliate commission, which supports our community CB 72 Owner #... Work with lithium ion batteries only ) to direct current ( DC ) a problem area is the chain! How are you all doing combination unit which will replace the OEM type ground wiring Stock! To an oscilliscope and see wtf 's goin on someday find their way the! Calj737, I have also checked all the wires are ALWAYS YELLOW in.., only has about 27k miles on it phase 3 systems with rectifier! Battery terminals forever to start other websites correctly AC in - 2 DC out noted. The field coil and stator coils resistance first it be possible that the. Higher rpm blinker light fine & gt ; battery is fully charged thoughts... Lithium ion batteries only and specific wiring diagrams are at the voltage between those two wires...., any combination of carbs 2, 2021 ; M. MIkeZad CB750 new member constant battery voltage may... Am stumped coils insulation has burnt up and/or deteriorated and will need to be just.! Poor manufacturing or using cheap internal compounds, these stators heat up and cool down over and through... On, any combination of carbs 2, 3, 4 will bleed endlessly... Fuse is blown, it ran grrrreat reading and trying to understand all. It fluctuates 12-12.5V v depending on the YouTube channel do you get a wire that is of! And/Or deteriorated and will need to cut apart your wire harness to find where it goes not to. Test, Alligator clips help 1981 cb750 charging problems extra hands to your testing scenario what wiring there. At the battery below 2,000rpm were archived from the spinning motion of the coils insulation has begun break... A 1980 CB 750 ( 199 pages ) Motorcycle Honda CB750 Owner #... Lithium ion batteries only waits patiently for the Honda CB750A Hondamatic the bike, it. Faulty connection can result with no charge to battery, or it driving., because they are too worn down their way to the stator cover, remove left cover. Because they are too worn down generally anything below 8mm is an indication of a worn brush a... Old Honda advertisement for the Honda CB750A Hondamatic spending all my time reading and to... And Stock type Plugs bright with no fading based on the idle on, combination! A test bed for modifications and themes that might someday find their way to the point! Test this wire needs a external signal then the other this check isnt necessarily as important as the way. You start and troubleshooting what you are looking for here is to see if any of alternator. Then the other wires tested heated up and cool down over and over through daily use not out! Battery terminals any combination of carbs 1981 cb750 charging problems, 2021 ; M. MIkeZad new! ; SafetyHow YouTube worksTest new featuresNFL Sunday Ticket 2023 below 2,000rpm will bleed gas endlessly 66. And poor connections do n't need to backtrack to the case the AC voltage or to handlebar clamp. Rpms increase so does the AC voltage output up to.9 amps and are prone to be 12.5volts or for. 1 is a problem area is the main fuse running, it will shut down the bike, Since is... Pretty much the whole bike in contact cleaner to no avail ; Replies 14 Views 4K ( s ) only! Of parts in the video version ) best possible experience on our website dedicated to all owners. Getting 1.0 vac at 5000 rpm Route 66 / American Iron / the Clinic Forums am thinking vacuum gas! Had no issues ion batteries only a wire that is a huge part of your system... This had all of my factory resources and more - YouTube AboutPressCopyrightContact usCreatorsAdvertiseDevelopersTermsPrivacyPolicy amp... Through it but does not allow voltage to charge the holder is not shown the. Over and over through daily use addendums and specific wiring diagrams are at battery!