The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: melvyndalby on 11.11. 2011 09:17

Title: RGS Break Light
Post by: melvyndalby on 11.11. 2011 09:17
When I apply my rear brake the brake Light works but my ameter does not show a discharge. I have the same problem with my Gold Star.Any sugestions?
Title: Re: RGS Break Light
Post by: alanp on 11.11. 2011 10:16
No worries, it just means that your stop lamp circuits are not looped through the ammeter and are linked from the battery. My RGS  brake circuit is from battery - fuse box - stop switch - lamp - earth. This is the BSA system, except they didn't fit a fuse box.
Title: Re: RGS Break Light
Post by: MG on 11.11. 2011 10:17
Hi Melvyn!

That is another case of "they all do that, Sir!"

The brake light is connected directly to the battery, as is the horn (maybe for reasons of safety, to avoid loss of both by a broken ammeter, dunno). Hence the ammeter doesn't "see" the additional load.
It's not a bug, it's a feature  *smile*

Cheers, Markus

P.S: Am willing to give your bikes a good new home in my garage if you can't live with the way they are wired  *contract*

PPS: Alan was faster. May I still have the bikes  ????
Title: Re: RGS Break Light
Post by: melvyndalby on 11.11. 2011 12:17
Thanks to Alan and Marcus for info.Why does the ammeter show a charge when? rear brake pressed and engine running?
Title: Re: RGS Break Light
Post by: LJ. on 11.11. 2011 12:45
I think its a very good modification to run the brake light through the ammeter... It is a reassurance that the bulb/switch/circuit is working. No need for the horn to go through ammeter as you hear that.
Title: Re: RGS Break Light
Post by: MG on 11.11. 2011 15:10
Quote
Thanks to Alan and Marcus for info.Why does the ammeter show a charge when? rear brake pressed and engine running?

With the battery being fully charged, the ammeter will naturally show no positive deflection. When the rear brake light is switched on, battery voltage will drop and the regulator kicks in and charges the battery (with sufficient rpm on the dynamo only of course), ergo the ammeter shows this charge.