Rattle in the alternator vicinity

Hello!

I have following puzzle in my bike. After start when charging lamp is on I can clearly hear a rattle around the alternator. When charging lamp goes down the rattle stops. Like the fact of full charging from the alternator brings some load to compensate a kind of freeplay. I do suspect bad conditon of alternator bearings. Oh and when the engine is cold it takes around 3000 rpms to turn the charging lamp off.
Any thoughts? Tips?

Best regards,

No 8 is what you're lookin' for.

Unfortunately the image doesn't show the way they are inserted, so have a looksy on the old ones. You'll find 'em hard as brick...

EDIT: You'll need three of those dampers. Make sure the connective bit of each of them is NOT put over the metal nose within the damper housing (the housing is seperated into 3 compartments. Each damper belongs within one of the compartments). You'll get what I mean once you see it in front of you...

I forgot to mention that I did an inspection of rubber inserts. What I noticed during inspection wast that the alternator spins with out a bearing drag. Normally new ball bearings have a distinct drag which I couldn't felt at the time.
I am curious why noise is related to charging or not charging by alternator.
I will try to go through the German thread with some help of translator.

Best regards

Some things I've found about my alternator over the years.

Even though the cush rubbers may be in good condition, it is quite easy to fit the alternator so that the drive vanes are not inserted correctly and separated by the cush rubbers, but are in fact touching each other. This makes a lot of noise at low rpm, but in my case, would go quiet at about 4,000 rpm when the speed of the alternator spinning pressed the vanes together so hard that they stopped rattling. There are alignment marks on the alternator to aid fitting it correctly.

The alternator consists of a rotor coil ( which rotates with the shaft) and three stationary stator coils. The voltage is applied to the rotor coil by means of the brushes onto two slip rings. The voltage applied to this rotor coil is controlled by the voltage regulator that modulates the brush voltage to regulate the output voltage from the stator coils. The brush and voltage regulator is one unit, is common (Bosch) and can be bought and replaced quite cheaply and easily.

The three stator coils produce a three phase alternating voltage that is rectified by 3 large diode circuits that produce a DC voltage. The output voltage of the alternator is sensed by the voltage regulator on the rotor circuit, so the output voltage is controlled by varying the input voltage to the rotor coil.

I have heard that alternators with a failed rectifier circuit on one of the output coils can be very noisy ( there's a video on You Tube) and wonder if one of your diode pairs has failed, resulting in a two phase output instead of three. This might explain why you have to rev it to 3,000 before the light goes off.

Also, be aware that the charging light works on the voltage difference between the alternator output and the battery positive voltage at the ignition switch. When the two are the same ( engine running - alternator producing) then the light goes out.
I also had a time when dirty ignition switch contacts caused the light to come on, but in this case, the light was lit because the voltage at the alternator output was greater than the voltage on the dirty side of the ignition switch.