You are right; you cannot know if it is the regulator or the altinator. The discussion about it being normal a bike dies after pulling the battery cable the actual reason why I've posted this video. On a Honda forum 99% of the visitors was convinced that it wasn't even possible to keep a bike running on idle without battery. I was the only one in this discussion who said it could and should. Seeing is believing. If your bike dies, I think there is a problem.

Hilarious 😂

mayby you can try this: charge your battery. Hook it up and if possible see how much it charges on the bike (should be more than 13 volts) If you cannot test the voltage and drive around in the neighbourhood. Lights on. If your bike stalls after a while the battery is not being charged and possible your altenator or regulator is not working properly.

Dear Menno/beste Menno. Thanks for uploading this movie. My Honda CB 650 (1979) wouldn't start anymore. I hooked it up (using jumper cables) to my car and guess what: it started right away. Can I now safely assume that the problem is with the battery that needs replacement? Or could the cause of failure still be located somewhere else? Thanks in advance mate, keep up the good work! Cheers

The causes can be many. Maybe your battery is old and doesn't keep its power. A broken battery draws power instead of storing it. You can simply test this by unhooking the battery and hang your bike on a car battery. It is however realy important to unhook your bike its battery. Otherwise; check wires for a shortcut or ask at a bike store with proper tools to test the electrical components. Cheers, Menno.

my 72 Cb500, is having charging problems. I tried this test with the old stator and the bike died immediately every time. So I replaced the stator with better results. With the new alternator it still dies, however if i rev up over 3000rpm it will stay running roughly until slowly coming to a halt.. So do you think I have burned out my regulator? would that cause the symptoms I am experiencing? all of the lights lights dim at an idle and the bike slowly dies.

Hi Johannes, does your bike keep running by itself after you started it with help of an external battery and after you unhooked it again? Then it is safely to assume the bikes battery is the only problem. Cheers, Menno.

Hi Menno, no, I performed your test and my bike failed to do so: the engine stopped working right after I unhooked the battery. But I have been doing some research on the internet and there are quite a few people saying this may be normal for a bike? And also, that it is very detrimental for the bike's electronics because the battery acts as a damper for harmonics. And how can you know from your test that is the regulator and not the alternator that is faulty? Thanks mate!

Hold up, how does it run without a battery? I thought you needed a certain amount of charge to keep the motor ticking.

Most bikes have to be over somewhere 2000 rpms or it will want to run off the battery.

So does this show that the voltage regulator is or bad?