Electrical question

 It used to be in auto electrics that if you tried fixing a system by
swapping  components with known good ones, you ran the risk of making the
wrong choice and could end up frying the known good one (which was why there
was a No Return policy on certain parts I am told). I don't know if that
still applies with cars, but does it in any way apply with bikes, as in
Honda CB650s for example?

Thanks, pflu

 


Yes. Pretty much anything, for example.

 

Your wit is underwhelming.  I asked this before (and it was not answered)
because I needed to know if it was OK to just swap out parts, as is often
reccomended. If you are smart you know that as technology changes what is
obvious is not always correct.

My system is not charging, so a guy gave me a regulator/recifier to try. He
fixes bikes and says most often that is the problem. He touched my
regulator/rectifier after I had been riding and said it felt cold but should
feel hot. When I installed the one he gave me it felt hot at first, so I
rode with it. Turns out the system still did not charge, but now this one
also felt cold. He says it may not have been a good one after all since it
was just in a box in his garage.

I want to know if maybe it was a good one and if I could have fried it
because of some other component malfunctioning, and, if possible, deduce
what that component would most likely be. If not, I can swap out more parts
as I find them. I'm asking for an explanation, not wisecracks here.

Thanks, Pflu

 

You may have noticed that a rectifier-regulator is built into a finned
aluminum heat sink. The heat sink gets rid of the heat generated by
the six power diodes inside, as they rectify AC current into DC
current.

However, if there is *no* appreciable AC input, the diodes aren't
going to make the rectifier  part of the rectifier-regulator get very
hot.

Previously, you mentioned that you weren't getting a good continuity
reading through the slip rings of your rotor.

The regulator part of the rectifier regulator senses battery voltage,
and it controls the field excitation current which comes from the
battery and goes through the copper wire field winding in the rotor.

Have you tried passing 12 volts from the battery directly through the
rotor while the engine is running?

Also, do you know for a fact whether the rotor is actually *turning*
as the engine runs?

Many an oldtime aircraft electrician was fooled by the fact that the
generator rotor wasn't actually turning as he troubleshot the voltage
regulator on a radial engine...

 

Oh, for *fuck's sake*.

A crankshaft spinning, while the rotor on the end isn't, is going to
make a noise so horrendous it might even penetrate your skull.

(Some Ducatis are known to have suffered this ailment)

--
BMW K1100LT  Ducati 750SS  Yamaha XT600E  Honda CB400F MZ TS250/1
chateau dot murray at idnet dot com
"What you're proposing to do will involve a lot of time
and hassle for no tangible benefit."