Failing regulator symptoms?

[Ben Slabby]

Rode back from Manchester to Leeds the other weekend, so not far. Ran fine, however cut out when I got home and on inspection, (the following weekend, earliest opportunity)  the battery was totally discharged. It wouldn't take a charge, which I put down to being left discharged. 

Anyhow... new battery on, bike behaves fine. Went for a short spin, tested battery, still at 13.5v. Great...

However, I seem to have acquired a flicker to my lights that's dependent on engine speed.. think of the "small capacity bike ticking over" type thing. All connections are good. Is the reg on its way out? I'm tempted to stick an ammeter in the battery feed to see if it's charging, but the flickering is baffling me. 

[Buzuki]

Well , it can be bad regulator ,or graphite brushes become to short , maybe graphite dust polluted rotor two cooper rings , also is good to check rectifier six diodes condition , but also it can be some bad contact anywhere in electrical installation ,

any way voltage regulator unit usually work good or is totally bad , is very rare that regulator is in some `overlap` condition between OK and bad .