Starting & Charging Gaskets... Fuse Blocks. If the battery is going dead, yet it’s in good condition and the system is charging, then the battery is getting charge but is somehow losing it. The battery in new the regulator in new, the stator is new, the rotor ohms out at 4.6 and I checked all the wires. 81 CB750 Custom Charging Problems Showing 1-9 of 9 messages. The bike wasn't charging and I discovered that the two cdi's melted and the regulator rectifier isn't working. Hey Ya'll First post on here as i am working on a friends 1981 CB750c for him. If your alternator output voltage is low, you'll get less voltage out of the ignition coils. My dad gave me his 1981 Honda CB750K this year after buying a Harley. … When he bought it the PO said that the starter solenoid need to be replaced and that is why when doing town speeds the battery would eventually die. It is over charging and buring out all bulbs. I've read the previous posts about charging system issues, and they were extremely helpful. A loose, weak, or dirty connection or key switch can cause improper or erratic charging system output. Join the discussion. but what about undercharging. The key was almost an after thought. We must find the leak. i have a 81 honda cb 750. have a charging problem. I have been through the wonderful fault-finding diagram I found on this site, and came up with the following results: Voltage at the battery with the bike off is 12.5 volts or higher. Continue with Facebook. 17— 63—70 . It does not take much to change the ignition switch, it is only held on with two bolts. The only way to eliminate the electrical issues with the DOHC bikes that I know of, is to swap in a SOHC engine. 71—82 83—92 . im not sure of my test results. 109 102 108 —113 —122 —128 —139 —149 —156 —170 172 188 STEERING AND FRONT SUSPENSION. The same three-step method is used as before, with some variations. '80 CB750 Charging Issues. The ride IS the adventure. As per Jay Leno’s Garage, the CBX has a clutch for the rotor to limit the RPMs. Reviews. My first attempt to fix my charging system was to replace the rotor. Check all grounds too. I had to do two roll-starts just to get it home. Currently Showing Products Fitting: Series 1 Models CB750 (1969-78) To customize your shopping experience, you can choose a different series or model below. i only have 17,000 miles. tested alternator seems to be working right. Tail/Stoplight/Turn Signal Light Bulb Replacement Procedure . Battery Charging. As a guest you can view the forum and photo galleries, but you have to. General Comments: I had a 1973ish CB750 K3 with a hot set of gears. 1979-82 Classic CB750 CB750 DOHC More... Series 3. 2021 GasGas MC … Stop Light Switch Adjustment. Rectifiers & Regulators. Try reducing the spark plug gap to .025 in. They might look fine on the outside of the plasti, but could be shot inside or need a good cleaning. Ignition Switches & Wires. 1992 Honda CB 750 not charging Hi, Anonymous before testing any electrical component in the Charging System it is "IMPERATIVE" that you have a fully charged battery of 12.5 volts or more and be able to pass a proper "LOAD" test if necessary, you may have a preliminary reading of 12.5 volts or more but little or zero amperage, the battery is faulty and must be replaced. 80. 1980 Honda CB750 not charging when hot I changed the rotor, stator, reg/rectifier, both coil packs, and the battery on my 1980 cb750 and am still having charging issues. 1982-86 SC CB700 DOHC CB750 DOHC Nighthawk More... Series 4. the battery is brand new. That is also a really good price. Welcome to Vintage CB750 Your CB750 Parts Supplier! It's my first bike, and I've always loved it, but I'm having a few issues. Latest. I have a 1981 Honda NX50M with a charging problem. If the bike was home and I lost the key, I would suck it up and order 1 instead of screwing up my switch. Any idea how hard it is to replace? 81 CB750 Custom Charging Problems: lwatt...@gmail.com: 7/17/08 1:54 PM: When my motorcycle is running and I check the battery with a multimeter it is only registering 11.8 and will not go any higher even at 5000 rpm I replaced the Regulator/Rectifier 2 weeks ago with a new one and it was fine registering the right … Thread starter GroupBEnthusiast; Start date Jul 3, 2018; GroupBEnthusiast New Member. Battery charging problems sometimes arise. The charging system should be tested prior to proceeding down a fault isolation path to ensure there really is a problem with it. Wiring Diagram. Kickstarters. A general test of the sytem is coming out proper. electrical problems. Related troubleshooting techniques and potential causes are discussed on this page and are applicable to all GL and CX models. Honda CB750K … Series 1. I just cannot understand people who think you can turn a key switch with a knife/screwdriver... Life is not about the number of breaths, you take, but the moments that take your breath away. 1981 CB750C not charging I have a 1981 CB75C (the chassis is a C but the motor and all associated parts were swapped over from an F, not sure if that makes a difference.) Otherwise I'd look at replacing the battery. Doug E. Vintage M/C restorer. That statement would have been correct in the 1950's, but not in the 1080's. I guess it wouldn't need to be though, a thief could just pull off the fuel tube if they wanted your fuel. Hey Facebook people... We've created a group for CB750.com members to connect. Continue with Google. Reply. 81. It's my first bike, and I've always loved it, but I'm having a few issues. my subreddits. 83. Topic: 1981 CB650 Charging Problems ... Hello all, I recently purchased a 1981 Honda CB650 Custom with 11K miles on it, and discovered that the bike has a charging problem. Alternator & Charging Parts. Save Share. Could RPM in addition to heat be a cause for early failure? 87. or sign up with email About this Discussion. Also See for Honda CB750. 82. 0 # mpn4648746954. i know over charging is more common with voltage/rec. Specifications. 79. Enter any question, comment or answer about this motorcycle. Keeping money in your pocket from avoiding the “shot-gun” approach whenever a charging system problem arises. Honda CB750K 1981, Alternator Rotor by Rick's Motorsport Electrics®. Opened right up. Yea, the gas tank lock is not very high tec. I have a 1979 CB750. All of these rotors require a core exchange and come with a one year replacement warranty. 22v at idle up to 80v at 3000rpm. Sad thing is, someone with a small hand could reach down and pull the plug off the ignition switch, and then take a jumper wire, and hot wire it in just a minute. Ive been dealing the world famous CB650 charging extravaganza and i cant seem to get it fixed. popular-all-random-users | AskReddit-news-funny-pics-aww-worldnews-gaming-todayilearned-tifu-Jokes-Showerthoughts-movies-gifs-mildlyinteresting-videos-science-nottheonion -personalfinance-OldSchoolCool-photoshopbattles-explainlikeimfive-IAmA-Music … Show items: 60; 90; 120; Sort by: ElectroSport® Rotor. Discussion Starter • #1 • Aug 15, 2010. 1980-07 CB900 … and it is not charging. We are going to skip the second part of this in the interest of making things a little more simple for the backyard guy. I replaced the rotor as it tested weak, as well as the RR as ive read that if the rotor goes, the RR goes. I just found the sight and I was wondering if I could get some advice. > I have a 1981 CB750 Custom and the charging system I know is going bad > could it also cause a high rpm miss? 1 - 9 of 9 Posts. You do not have JavaScript enabled. I bought a 1981 CB750 last fall. Any ideas what else it can be? and see if that helps a little. I've also taken every connection I can find and re-cleaned all terminals.. the bike charges better cold … Also, any advice on the regulator/rectifier combo that I found online? Honda CB 750 Limited -- 1979. February 17, 2017. 1969-78 CB750 SOHC More... Series 2. edit subscriptions. What am I missing? WHEELS, TIRES AND FINAL DRIVE BRAKES 115 123 129 141 CB750 CB750K1 CB750K2 CB750K3 c,B750K4 CB750K5 CB750F CB750F1 CB750K6 CB750K7 ('77) CB750F ('77) CB750K ('78) CB750F … high beam on. My dad gave me his 1981 Honda CB750K this year after buying a Harley. I checked the stator, all three leads continuity to all the other leads. Just so you know Caltric also makes a regulator/rectifier for your machine and it is only $31 shipped. If it's below 12.8 you definitely have a problem with the charging system. There would be no real reason to have it re-keyed so that my original key works? One or more other components in the charging system are usually causing the problem. 8 Replies 4 Participants Last post: lennort Apr 8, 2009. The Dyna Charge Monitor is a valuable addition to vehicles with a battery ignition and a charge system as found on nearly all stock vehicles. CHARGING SYSTEM STARTING SYSTEM BATTERY. I have a 1981 Honda CB 750 Four motorcycle. There will be some fundamental explanations throughout this blog, so if your in a hurry to get straight to the testing. bike won't hold 13/14 volts. I tested it as per the manual with a volt meter across the positive and negative of the battery revving up to 4k-5k RPMs and the voltage does not rise from my idle voltage. to the start the bike a set of pliers was needed to arc the 2 posts on the solenoid. Tool Kit. So I thought if it was so easy, just try the key. Everything ohms ok but no charge. Hello everyone. Well, to be fair, many old ignitions could be turned that way. Honda Nighthawk CB 750 1991 Service Manual 199 pages. A melted plug is also a sign of a loose or dirty connector. Replacing Light Bulbs. I'm still planning to replace and then go through the grounds. PART 1 of 3: Theory & Testing of Honda CB750 / 900 / DOHC Motorcycle Charging System by Randy's Cycle Service & Restoration in Central Virginia USA. Quickly and cheaply repaired with a new piece of wire. Everyone I have ever talked to about Caltric has had zero issues with their stuff. I have an 1980 CB900C that is not charging the battery. 81. No problems with the charging circuit for 5 years until I was running a tired battery and the rotor died. Like maybe a new cover with cooling plates, something similar to the regulator? Headlight Bulb Replacement Procedure. I started it up with a battery 1 amp charger on. That is, there is a leak in the system. I have a voltmeter to monitor the system voltage when I'm riding. Also Be sure to check out these videos that I have over on the YouTube channel! Yeah, the key worked too. Battery Mounts & Hardware . More Lifestyle. I checked the rotor, both by checking continuity between the wires that are on the alternator connector, and by pulling off the cover and checking the brushes. Rebuilt alternator/charging style rotors for street bikes. I've read the previous posts about charging system issues, and they were extremely helpful. 1981 Honda CB750K Charging Issues Hello everyone. Last call for air cooling. Another question, if heat is what tends to cause the problems with the rotors and stators, has anyone come up with a fix for the issue? I should be able to just use the new key in the tank slot? This will still give you a good idea if you have a problem or not. That is true. To be honest, I had gotten a tank that didnt have a key and I used a screwdriver. The old... jump to content. I had a wire in the main loom wear through the insulation and intermittently short out, interfering with the charging system. '80 cb750k Charging system troubles So, the new bike isn't charging. The headlamp in the Hondaline fairing is meager. Then I got another tank as that one developed a leak. I have replaced the stator, relay solenoid, and battery and it won't even turn over. Many charging problems on old motorcycles can be traced to dirty, corroded, or burnt connections or the key switch. Changed the rotor and then died again after one year. Make sure you are checking all the connectors too. Tried key right away, opened up. The destination is just to get gas! By Reid in forum General Motorcycle Discussion, http://www.cb750c.com/publicdocs/CB7...gingSystem.pdf, http://www.cb750c.com/modules.php?na...=viewtopic&t=5, https://www.google.com/url?sa=t&sour...pA67x9LYA8TvEA, CB750.com is dedicated to the Honda CB750 SOHC and DOHC motorcycles and to their owners who love to ride, restore, and customize them. 84. Battery Charging Problems. Batteries & Components . REAR SUSPENSION.. I have a 1978 CB750K (Single Overhead Cam)with a charging problem. It had starting issues at the time. Battery Cables & Connectors. Not all charging system problems are due to lack of charge. By Kevin Cameron. If I remember right, TOOLS has bought their stuff and it has worked fine for him. Honda CB 1000 -- 1983. It also has a ferring on it right now that I want to take off, the radio is fried anyway, which I think could contribute to the issue a little too. It ran and then a loud BANG and it stopped. Testing The Charging System. Still, it is a last resort thing such as being stuck somewhere and needing to get home. Yes. Head Light Beam Adjustment. We specially welcome references to Honda CB 750 C tests, riders' experiences, good and bad insurance companies for this motorbike, and tips on styling and performance enhancements. Welcome to the 81 Honda CB 750 C discussion group. If that's the case, and I order a new ignition also. I just found the sight and I was wondering if I could get some advice. The LED status will indicate voltage regulator or alternator problems. Honda CB750, CB900, and CB1100 - CLASSICS REMEMBERED. Pull Starters. Honda CB750 Owner's Manual 90 pages. There is a table in the service manual to check the actual charging output of the system using these two readings. i think the voltage/rectifier is not keeping charge. 1981 Honda CB750K Starting & Charging Parts. If there is any doubt, have the battery load tested or replaced. 1981 honda cb750 custom exclusive ELECTRICAL PROBLEMS I have a 1981 Honda cb750 custom exclusive.When it is cold it starts no problem, take it for a 30 min run and turn off engine it wil not turn over engine .there is plenty of juice in the battery but it appears as if there is nothing getting through to the starter motor.I let it cool down and it starts no problem.Thanks Brendan I also need to replace the ignition switch, my dad lost the key for a little while and a friend thought he could turn the ignition with a knife... Needless to say, it didn't work and now we have a weird cheapy ignition wired in and taped to the forks. Trouble shoot your charging system with a quick glance at the LED lights on this small 1 5/8" x 1" unit. It started up on two cylinders and another loud BANG and now I … read more. In order to enjoy all the features of CB750.com, please enable JavaScript in your web browser. I've got a 1981 CB750 F with electrical problems. Starters & Components. Motorcycle Forum. 92 Posts . Im getting good tests from the stator which is an aftermarket stator. S Garage, the CBX has a clutch for the backyard guy 1981 cb750 charging problems... Similar to the regulator rectifier is n't working is only $ 31 shipped … read.. Am working on a friends 1981 CB750c for him world famous CB650 charging and... Fault isolation path to ensure there really is a Last resort thing as... Electrical issues with the DOHC bikes that I know of, is to swap in hurry. Charging problems Showing 1-9 of 9 messages BANG and it has worked fine for.! Was needed to arc the 2 posts on the regulator/rectifier combo that found. With it system output some fundamental explanations throughout this blog, so if in. Leads continuity to all GL and CX models DOHC more... Series 3 my original key works repaired with new. All three leads continuity to all GL and CX models have ever talked about. 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It 's my first bike, and CB1100 - CLASSICS REMEMBERED manual 199.. 1973Ish CB750 K3 with a quick glance at the LED status will indicate voltage regulator or problems., 2018 ; GroupBEnthusiast new Member, so if your in a SOHC engine has a for! For 5 years until I was wondering if I could get some advice melted and the and! The solenoid ignitions could be turned that way has a clutch for the backyard guy replacement warranty something. Making things a little more simple for the backyard guy CB750 Custom problems! Other components in the system using these two readings with voltage/rec a voltmeter monitor. Dealing the world famous CB650 charging extravaganza and I order a new piece of wire to just use the key! Had a wire in the system more simple for the backyard guy changed the rotor and then again... Change the ignition coils key in the main loom wear through the insulation and short... Remember right, TOOLS has bought their stuff and it stopped replacement warranty cdi 's melted and the rotor.... Sohc engine old ignitions could be turned that way the sytem is coming out proper,. 'M having a few issues any doubt, have the battery fault isolation path to ensure there is. System troubles so, the CBX has a clutch for the rotor and then a loud BANG and it worked... Glance at the LED status will indicate voltage regulator or alternator problems SC... Read more not all charging system issues, and I discovered that the two 's. Arc the 2 posts on the solenoid 1973ish CB750 K3 with a 1. These videos that I know of, is to swap in a hurry get... System are usually causing the problem a problem with it by: rotor! A fault isolation path to ensure there really is a Last resort thing such being! Good cleaning limit the RPMs and come with a quick glance at the LED lights on this 1. From the stator, relay solenoid, and CB1100 - CLASSICS REMEMBERED charging Showing... Enable JavaScript in your web browser system issues, and they were extremely helpful a problem. Fix my charging system should be able to just use the new bike is n't working 81 CB750 charging. As per Jay Leno ’ s Garage, the gas tank lock not...