Cool. Make sure you test the regulator/rectifier. Sometimes once the rotor goes, it will take the reg/rec with it. I can upload the service manual to my site if you don't have it.
The right way to use a digital ohmmeter on low ohms is to short the test leads together, note the reading and then subract that reading from the result. This will compensate for the resistance of the test leads.
Just picked up an '81 CB650. The seller had work done last year and the wrench at Honda said the stator needs replacing. I ordered the stator and the rotor figuring from what you showed the rotor would probably need replacing anyways, better to be safe than sorry I guess.
You need to find out why it is not charging, otherwise it can get expensive and frustrating. You can inspect the rotor. The insulation usually deteriorates and it shorts out. You can check the rotor & stator with a multimeter. You can check the output of the alternator. Also, you can check the reg/rec unit.
Thanks I will. Had trouble getting a screw out and snapped off a brush, so in ordering a new set I went ahead and got a new rectifier/regulator. Should be pretty much new when I finish. A bit pricey but I'd like reliability and I'm not paying for labor.
No I didn't. The bike is still at his house, I was going by what he told me. Do you think at least the rotor was a good idea? For sure it is not charging. Being in Canada most parts have to be ordered from the State's, so things are not cheap. But I do like the bike and my test ride showed it to be running very well. Thanks.
Bonjour Ayant le même problème votre vidéo m’aide beaucoup. Mon rotor est entre 3,9 et 4 ohms. L’isolant est dans un état satisfaisant. Cependant j’ai mesuré mon stator entre les files jaunes. J’ai 0,6 et 0,7 alors que je dois avoir entre O,41 et 0,51 ohms. Qu’en pensez vous ?
When I went to put the cover on it was a little tight with the Stator fitting on the Rotor. Gave it a little tap with the mallet and she settled nicely. Before I replaced the Rotor i had no issues with the fuses, Now I'm wondering if I fried one of the other charging units.
How easy should it be to pull the axle out? Book says you gotta do a lot of loosening of bolts related to the brake and chain tensioner. Was hoping you could just slip it out then back in
I have no idea how to check the regulator. I did order the manual for the bike. If you could tell me how to check it though I would really appreciate it as I'd order one if it's bad. Still to cold here for riding anyways. Thanks for your help.
forgot to mention that I'd intend to clean it up and ride it but as I get used to it, chop the rear and turn it into a bobber style with mini ape hangers.
would a bad rotor or stator cause the bike to stall after running for about 10-15 minutes and have issues starting while still hot? I have an 81 cb650 with this issue
@@soulchief1532 Have you hooked a multimeter up to see if it is charging? But to answer your question, yes a bike will eventually die if charging system is not functioning.
@@HTMR I did hook it up yesterday and it was charging fine at idle, it got up to about 14 volts when I started opening the throttle a little and getting it warm. Maintained about 13.1 after that. Then I shut it off and it dropped clear down to 12.1 and wouldn't start
@@soulchief1532 I had a similiar situation on this bike. Turns out the rear brake switch was always "closed", so brake lights were on all the time (2 bulbs) and it killed the battery. So I would suggest pulling one fuse at a time and see if your problem goes away. There might be an electrical load that is not supposed to be on. This goes to show that stock charging system is marginal.
MatthewMCRepair yes it is after 3 days of research, wire diagrams, and frustration trying one thing after another spending way more money than needed, I found this video now with a great relief its charging and I have a lot of back up parts if anything else goes. and the rear axel trick worked great. I have a 1982 cb750f I used it on
The rotor was purchased on ebay since cost was less. It was a rebuilt with core charge. The boots can be bought any place online that sells OEM honda parts.
Hello Matthew MC, Im running good (4.6) on the Ohms interrings. but checking the the same ring ohms , i am getting 1.2 on both rings (consistent). Would this indicate a faulty rotor? Thanks
You should get 0 ohms on the same ring. Lightly clean the surface and try again. This test really does not mean anything other than you have continuity on that ring.
MatthewMCRepair so how about when I test the charging rotor like you did ,it just beeps and grounds out like I’m touching the 2 ends together( I apologize for all the questions I just can’t find a shop to touch it)
hi. I found a 1981 cb650C in a junkyard for $400. The guy says it runs. It has 18k on the odometer. I am wondering if this is a bike that's pretty good? Ive never owned a moto before and am pretty mechanically inclined BUT I've never worked on a bike or a carb before. Are these pretty cool bikes? Pretty inexpensive to fix up? thanks so much!
I have a problem with my 81 cb650. sometimes it will start up all day with no issues, but other days i will need to jump start it. some days its doesnt't start at all... just today it shut off on me at a red light. I just tested the battery and its all good??
Hello! I have a piece of shit '80 CB650 that just randomly started running on three and misfiring. New spark plugs didn't do a thing. Could this be the problem?
I may be one of the few that this trick (or the actual OEM puller for that matter) didnt work. I had to use the puller, a cutting torch, and persuasion with a hammer to get the damn rotor off.
hey, first off, really nice video it helped alot, i have a question tho, when i test my rotor like you did im getting like 1.5 - 2 ohms, you said that its between 4.2 and 5 so does that mean that my rotor is done? im looking into it because my battery is not charging, so would that be my problem you think?
+MatthewMCRepair i did not, i will do that and test again, something is off for sure, regulator isnt problem because thats been changed so im thinking stator or rotor
Was doing some research and it's definitely an aftermarket one, that's good for you! Might get one myself. Looks like it's an Electrosport Industries: cl.ly/0x1m1I2e2m0V
my rotor went bad with no continuity brtween the rings . I bought a puller for 5 bucks went down to the junkyard and got an identical one from a cb900 for 20 bucks and never had a problem with it again .
I did check the rotor and there was no reading at all. So glad I ordered one. Thanks to your instructions I got it off with the axle.
Cool. Make sure you test the regulator/rectifier. Sometimes once the rotor goes, it will take the reg/rec with it. I can upload the service manual to my site if you don't have it.
I don't have any vids or writeups on reg/rec. You'll need a multimeter. The manual does a good job explaining the procedure.
The right way to use a digital ohmmeter on low ohms is to short the test leads together, note the reading and then subract that reading from the result. This will compensate for the resistance of the test leads.
Okay......where is the video showing the testing of the repaired charging system? I like your no nonsense approach to these videos. Well done.
I've got the manual now and it does a good job. Thanks for all your help and I'll continue to check out the excellent vid's you put out.
Kitapcığı bulamadım yardımcı olurmusunuz
Just picked up an '81 CB650. The seller had work done last year and the wrench at Honda said the stator needs replacing. I ordered the stator and the rotor figuring from what you showed the rotor would probably need replacing anyways, better to be safe than sorry I guess.
Yes, have fun & learn with it! Inexpensive? Depends on how much it needs.
You need to find out why it is not charging, otherwise it can get expensive and frustrating.
You can inspect the rotor. The insulation usually deteriorates and it shorts out.
You can check the rotor & stator with a multimeter. You can check the output of the alternator. Also, you can check the reg/rec unit.
Thanks I will. Had trouble getting a screw out and snapped off a brush, so in ordering a new set I went ahead and got a new rectifier/regulator. Should be pretty much new when I finish. A bit pricey but I'd like reliability and I'm not paying for labor.
Did you test the stator? They usually don't go bad. Congrats on the new bike!
No I didn't. The bike is still at his house, I was going by what he told me. Do you think at least the rotor was a good idea? For sure it is not charging. Being in Canada most parts have to be ordered from the State's, so things are not cheap. But I do like the bike and my test ride showed it to be running very well. Thanks.
Keyster makes good kits. Also check Randakks, however I think it is for 750's and up.
Bonjour
Ayant le même problème votre vidéo m’aide beaucoup.
Mon rotor est entre 3,9 et 4 ohms.
L’isolant est dans un état satisfaisant.
Cependant j’ai mesuré mon stator entre les files jaunes. J’ai 0,6 et 0,7 alors que je dois avoir entre O,41 et 0,51 ohms. Qu’en pensez vous ?
Stators rarely go bad. Check resistance between each white wire leg...should be about .5ohms. White wires should not have continuity to ground.
Definitely let me know how it turns out.
Awesome vid!
Guess what I am probably going to be doing in next couple days...
Thanks and good luck!
The rear axle on my 1981 CB650 Custom does not fit the rotor threads. Still in search of 17mm x 1.5 bolt to get the rotor pull off of the crankshaft
how much work is involved in removing the rear axle?
When I went to put the cover on it was a little tight with the Stator fitting on the Rotor. Gave it a little tap with the mallet and she settled nicely. Before I replaced the Rotor i had no issues with the fuses, Now I'm wondering if I fried one of the other charging units.
Haha you think yours is dirty, I'll buy it! Looks like you keep your stuff clean and in top condition. I need a new one too, needed really.
Hopefully it solves your charging problem.
¿Dónde consigo guía de cadena de distribución? Tengo el motor RC03E
How easy should it be to pull the axle out? Book says you gotta do a lot of loosening of bolts related to the brake and chain tensioner. Was hoping you could just slip it out then back in
Thanks for video, The idea with The axle saves my day.
Bought a rewound one from ebay. New OEM ones are crazy expensinve!
how long did it last?
I have no idea how to check the regulator. I did order the manual for the bike. If you could tell me how to check it though I would really appreciate it as I'd order one if it's bad. Still to cold here for riding anyways. Thanks for your help.
I can’t get the rotor bolt lose at all any tips? Tried everything
cb750 nighthawk 1982 let me down on first day out on it
forgot to mention that I'd intend to clean it up and ride it but as I get used to it, chop the rear and turn it into a bobber style with mini ape hangers.
would a bad rotor or stator cause the bike to stall after running for about 10-15 minutes and have issues starting while still hot? I have an 81 cb650 with this issue
Does the battery die and unable to crank it over?
@@HTMR yes, although once it is cooled down it regains enough voltage to start it again
@@soulchief1532 Have you hooked a multimeter up to see if it is charging? But to answer your question, yes a bike will eventually die if charging system is not functioning.
@@HTMR I did hook it up yesterday and it was charging fine at idle, it got up to about 14 volts when I started opening the throttle a little and getting it warm. Maintained about 13.1 after that. Then I shut it off and it dropped clear down to 12.1 and wouldn't start
@@soulchief1532 I had a similiar situation on this bike. Turns out the rear brake switch was always "closed", so brake lights were on all the time (2 bulbs) and it killed the battery. So I would suggest pulling one fuse at a time and see if your problem goes away. There might be an electrical load that is not supposed to be on. This goes to show that stock charging system is marginal.
Selam bende 1982 model cb 650 var şarj yapmıyo yardımcı olabilirmisin
great video. after watching I got the job done in less than 30 min.
Good job Jason. Is it charging again?
MatthewMCRepair yes it is after 3 days of research, wire diagrams, and frustration trying one thing after another spending way more money than needed, I found this video now with a great relief its charging and I have a lot of back up parts if anything else goes. and the rear axel trick worked great. I have a 1982 cb750f I used it on
Jason Ramsdell Great to hear. Electrical gremlins are tough.
Hi MatthewMC,
I'm working on the exact same bike and was wondering where you got the parts such as the carb boots and the charging rotor? Thanks
Derek
The rotor was purchased on ebay since cost was less. It was a rebuilt with core charge. The boots can be bought any place online that sells OEM honda parts.
Hello Matthew MC, Im running good (4.6) on the Ohms interrings. but checking the the same ring ohms , i am getting 1.2 on both rings (consistent). Would this indicate a faulty rotor? Thanks
You should get 0 ohms on the same ring. Lightly clean the surface and try again. This test really does not mean anything other than you have continuity on that ring.
Wont hitting the rotor like that cause it to lose magnetism? Same as hitting the cover with a hammer or dropping the rotor all together?
No.
Is there anything else other than the rotor/stator or rectifier that’ll keep it from charging?
Sure, a bad battery. Also, a high power draw on a device that should only be on momentarily (brake lights etc..).
MatthewMCRepair so how about when I test the charging rotor like you did ,it just beeps and grounds out like I’m touching the 2 ends together( I apologize for all the questions I just can’t find a shop to touch it)
I got the CB900F super sport I replaced rectifier, stator & flywheel kit even the brushes and still no go all the wrg is good at this point im stuck
Luc Rancourt How are you testing the charging system? At idle and at a higher RPM?
hi. I found a 1981 cb650C in a junkyard for $400. The guy says it runs. It has 18k on the odometer. I am wondering if this is a bike that's pretty good? Ive never owned a moto before and am pretty mechanically inclined BUT I've never worked on a bike or a carb before. Are these pretty cool bikes? Pretty inexpensive to fix up? thanks so much!
I have a problem with my 81 cb650. sometimes it will start up all day with no issues, but other days i will need to jump start it. some days its doesnt't start at all... just today it shut off on me at a red light. I just tested the battery and its all good??
+Dali Ramon What are your symtopms when it does not start? Does it crank? Do you just hear a click sound? Be a little more descriptive.
looking for a new rotor myslef, seems changing it is easier than finding it. know any places? whered you get yours at?
Yes, nothing like being stranded with a dead battery.
Any reason why after I changed the rotor my main fuse blew and the bike was dead. I put in a new fuse and it melted instantly.
Not sure, but you do have a short somewhere.
Hello! I have a piece of shit '80 CB650 that just randomly started running on three and misfiring. New spark plugs didn't do a thing. Could this be the problem?
Would check points or cdi boxes if you have the electrical point system. Then would check coils.
I may be one of the few that this trick (or the actual OEM puller for that matter) didnt work. I had to use the puller, a cutting torch, and persuasion with a hammer to get the damn rotor off.
hey, first off, really nice video it helped alot, i have a question tho, when i test my rotor like you did im getting like 1.5 - 2 ohms, you said that its between 4.2 and 5 so does that mean that my rotor is done? im looking into it because my battery is not charging, so would that be my problem you think?
Did you clean the slip rings before checking?
+MatthewMCRepair i did not, i will do that and test again, something is off for sure, regulator isnt problem because thats been changed so im thinking stator or rotor
Check out this troubleshooting chart from Motorbike Mondays: motorbikemondays.com/wp-content/uploads/2015/10/rte_troubleshooting_flow_chart.pdf
My rotor usually hovers around 3.9 and 4 ohms. I saw that you were getting about that on the new rotor. Would you say this is fine to use?
Yes. Is the insulation/coating on windings in good shape?
Clymers says .4-.5 ohms between slip rings
So did the charge after u worked on it?
If the bike still has a centerstand, not much at all.
exactly what i needed thanks
I like you videos man! keep it up!
Great video. What Stator is that you have there? It looks nice and heavy duty and not stock. Thanks.
I have no idea. I assumed it was stock.
Was doing some research and it's definitely an aftermarket one, that's good for you! Might get one myself. Looks like it's an Electrosport Industries: cl.ly/0x1m1I2e2m0V
Actually that's a completely wrong image, that part #ESF901 is actually a rotor and not stator. Oh well. It's aftermarket.
aermotorstudio Nice find. The "blue" part is a stator. The rotor is the part that spins. The stator "stays" in place.
Yea I understand that. I ordered a new stator, rotor and reg/rect. Hope that will set me up right.
can you link me to where you bought a new one?
Thank you.
Search ebay.
My rotor only shows 1,5 ohm. Does that meen its bad. The rectifier shows nothing
Did you clean the slip rings? Same year make model?
MatthewMCRepair well i sprayed some elecric cleaner on it. I will try and use some sandpaper. I only got 12 v on My battery at high rpm
MatthewMCRepair and My stator shows 0,6 between the three yellow wires
MatthewMCRepair yes i did and removed it. Still 1.5. I will buy a new. But ill probably wont find one here in sweden
my rotor went bad with no continuity brtween the rings . I bought a puller for 5 bucks went down to the junkyard and got an identical one from a cb900 for 20 bucks and never had a problem with it again .
joseph bourdeau Good deal. There are no MC junkyards around where I live.
is it back axle from cb650?
Yes
So if I have 0 ohms that means my rotor is toast?
I hate when that happens.
That sucks!