Lights dimming when brakes applied???

[posplayr]

I don’t understand the r/r vdc numbers?
what are you measuring?

[Guest]

The battery voltage does drop from 12.5 to 11.9 when the brake is depressed, the charging system was replace a few months ago due to the notorious GS issue, bot the stator and R/R are new.

What type of RR did you install?

[Qumodo]

measuring the output of the R/R, positive lead to the red line out of R/R, negative lead to ground on frame.

[Qumodo]

it is a Caltric R/R

[Steve]

Here are the numbers from the test.

1.) key off................12.7
2.) key on .....12.2

3.) at idle 1500 rpm.....12.9

4.) at 2500 rpm.......13.2

5.) at 5000 rpm.....13.7

6.) key off.....13.2

It seem like the battery is under charged or weak.

At 5K RPM you should be closer to 14.5V unless:

Bad connections at the R/R.
Bad battery
under charged battery.

13.7 volts at least shows that there is <some> charging going on.

How soon after starting the bike did you read that 13.7 volts? If the battery is low (even though it shows 12.7 at the start), the effort of starting the bike might take a while to charge the battery. It won't show 14+ volts instantly, it may take a few minutes of riding over 3000 RPM to get it up there.

The stator numbers look good, but your Vdc numbers are TERRIBLE. You either were not measuring correctly or the R/R is faulty. It does not really matter which, you will do yourself and your bike a favor if you replace your R/R with an SH775.

.

[Guest]

it is a Caltric R/R

Shunt type, bad bad bad. SH775 is what you want.

[posplayr]

it is a Caltric R/R

You probably just burned up your stator again using that shunt R/R.


You did not do the leg to ground tests (test for isolation 0 VAC) at 5K RPM in Phase B of the stator pages.

[Gorminrider]

battery voltage does drop from 12.5 to 11.9 when the brake is depressed,

this makes no sense if your key-on test shows 12.2...?The key must be on to activate brake light....but I'm just nitpicking. ANY load will drop your system voltage if the bike isn't running...as to how much it drops it, it's the amperage demand. Your headlamp, for instance draws far more than a brakelight....and, do you have any extra accessories on the bike?
need say, before anything, connections,connections,connections...If things have changed since you first installed the new parts, this is the place to start and especially at any wiring in the vicinity of any projects you've done on the bike...


If you suspect the brake light circuit, pull it's fuse and see if your Charging voltage improves at battery. You can pull the headlamp too.

I don't have a caltric stator, but I know that I can easily wind a stator to produce 80 volts without it having amperage output.Or, perhaps the regulator is at fault. Is it hot?...but everything else aside, you can run along just fine with 13.7 at the battery given the bike starts and runs correctly and reliably and you really can't find anything wrong...and you refresh the battery every month or so on a good battery charger to give it a higher rate occassionally or just turn your headlight off when warming up the bike.