The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: Pecon on 23.01. 2013 14:31

Title: Ammeter quality
Post by: Pecon on 23.01. 2013 14:31
Hi all

  Can anybody point me in the direction of somebody who might be able to suppily a decent quality ammeter?. Everytime I switch on my lights the ammeter needle dances all over the place before settling down. I have read that some have some type of stabiliser built in which lessens the movement of the needle. I have bought a few over the years on eBay but they all seem to act the same.

Peter
Title: Re: Ammeter quality
Post by: LJ. on 23.01. 2013 14:42
Hi Peter,

I find it hard to see how the needle dances all over the place when you put your lights on. Do you mean when the motor is running and is stationary on centre stand? I believe smaller movements are due to regulator oscillation (correct me if I'm wrong someone) in which case cleaning up contacts and generally checking wiring would be in order. An electronic regulator may well stop erratic movement too. There is indeed a small damper screw on the back of some older ammeters but you should check your system before twiddling the damper.
Title: Re: Ammeter quality
Post by: Pecon on 23.01. 2013 14:59
Hi LJ

   I've just finished installing a dynamo belt drive and upgraded to a DVR2 regulator (imagine my surprise when I dismanteled the old reg and found that somebody had beaten me to it by installing a Vreg in the box). The ammeter has always acted this way so it's nothing to do with the changes. When the engine is running and the lights switched on the needle flickers from side to side for several seconds before settling down. Not I suppose a huge problem but it is very irritating to say the least. I have read that original Lucas units had a damper screw and wondered if something similar might still be available or just one which is slower to indicate?.

Peter
Title: Re: Ammeter quality
Post by: Triton Thrasher on 23.01. 2013 18:05
I've heard of people filling the ammeter with oil.