The BSA A7-A10 Forum

Technical => Lucas, Electrical, Ignition => Topic started by: Buster1450 on 30.12. 2010 10:51

Title: Could my Regulator be sticky?
Post by: Buster1450 on 30.12. 2010 10:51
Morning Chaps,
I have another question I would appreciate your help with.
Could my Regulator be sticky?
The volt meter some times shows that I am getting a good charge up to +7 and the next time I start the bike it dose not register any charges at all.

Any thoughts?

Regards,
Buster,
Title: Re: Could my Regulator be sticky?
Post by: BSA_54A10 on 30.12. 2010 11:14
The bike should have an amp meter fitted not a volt meter.
The regulator controls the out put from the generator.
It measures the voltage at the battery to do this and only turns on when there is a load ( battery flat  or headlamps / stop lamp on ).
As such most of the time it should read "0"
The generator only charges 6 Volts at speeds from around 1/4 throttle so when at idle expect to see a - value.
At around 30 mph in top gear when you put your foot on the brake the amp meter should go - for a few seconds then go + for a minute or two to replenish the battery.
Unless your bike has been "fiddled with" it should be 6 V and + earthed.
Title: Re: Could my Regulator be sticky?
Post by: Buster1450 on 30.12. 2010 11:25
Hi,
My mistake it is an Amp meter. should it register a charge when reving the engine with the bike stationary?
It is + earth.
Regards,
Title: Re: Could my Regulator be sticky?
Post by: bsa-bill on 30.12. 2010 12:01
Not if the battery is fully charged and in good nick.
To test it run the bike with the lights on it should show a discharge at tickover and return to centre or above when revved up.
Title: Re: Could my Regulator be sticky?
Post by: Buster1450 on 30.12. 2010 15:13
Hi Bill,

With the bike ticking over and the lights on I am indeed showing a negative but the amp meter stays at a negative when I rev the bike.

The battery is brand new and fully charged

This has been the case since I got the bike a few weeks ago but a couple of days ago the amp meter worked and showed a positive when I revved the bike but it has gone back to not working.

That is why I thought it could be a sticky regulator.
Any thoughts?

Regards,
Buster
Title: Re: Could my Regulator be sticky?
Post by: fido on 30.12. 2010 15:36
It is worth cleaning the contacts of the mechanical regulator the same way as you would clean contact breaker points for the ignition. If you have a multimeter you can also check that the dynamo is working. To do this you remove the 2 wires and join the 2 terminals together with a piece of wire. You now connect your red meter probe to a suitable earthing point on the engine and the black probe to the joined up dynamo terminals. Select a suitable DC voltage range on the meter and start the engine. At fairly low revs you should get perhaps 10 volts, increasing as the revs go up. If you get no volts you may have worn dynamo brushes or a broken dynamo chain.
Title: Re: Could my Regulator be sticky?
Post by: Buster1450 on 30.12. 2010 16:05
Thanks Fido,
I will give that a go tomorrow.
Off to the pud now.
Later,
Buster,
Title: Re: Could my Regulator be sticky?
Post by: MG on 30.12. 2010 19:15
Hi Buster!

A lot of Lucas workshop manuals are available for download here:
http://www.bolsover.com/lucas/ (http://www.bolsover.com/lucas/)

If you follow the instructions for the regulator box you can't go wrong.

Cheers, Markus
Title: Re: Could my Regulator be sticky?
Post by: Buster1450 on 31.12. 2010 14:40
thanks MG I will give it a go soon.
Have a happy new year.
Buster