Lights, capacitors, action.

Information relating to the Matchless G3 or AJS Model 16 350cc Heavyweight
Post Reply
The Vandal
Member
Posts: 79
Joined: Fri Sep 16, 2022 7:43 pm
Location: West Sussex UK

Re: Lights, capacitors, action.

Post by The Vandal »

Yeah I agree with you all about the battery, luckily it should be here tomorrow so fingers crossed!
The Vandal
Member
Posts: 79
Joined: Fri Sep 16, 2022 7:43 pm
Location: West Sussex UK

Re: Lights, capacitors, action.

Post by The Vandal »

Battery has arrived, it's tiny!

The ebay listing says to charge prior to use, have you guys adhered to that or...?

Just I've realised that any charger I have will be for a 12v battery not 6v.
Andy G
Member
Posts: 358
Joined: Mon Jun 01, 2020 9:42 am
Location: Aberdeenshire UK

Re: Lights, capacitors, action.

Post by Andy G »

Got spare six volt battery? Charge them in series...
Or add a 6v load like a bulb and charge the one.
Or let the bike do the charging!
Bombling contentedly around rural Aberdeenshire
The Vandal
Member
Posts: 79
Joined: Fri Sep 16, 2022 7:43 pm
Location: West Sussex UK

Re: Lights, capacitors, action.

Post by The Vandal »

Andy G wrote: Thu Sep 22, 2022 6:28 am Or let the bike do the charging!
I like this idea!
The Vandal
Member
Posts: 79
Joined: Fri Sep 16, 2022 7:43 pm
Location: West Sussex UK

Re: Lights, capacitors, action.

Post by The Vandal »

I think my old man has a newer optimate actually so it might be 6v/12v switchable.
User avatar
Joker_Bones
Member
Posts: 539
Joined: Sat Apr 27, 2013 3:51 pm
Location: DORSET UK

Re: Lights, capacitors, action.

Post by Joker_Bones »

if it's an AGM battery, the ones I've had arrive pretty well charged.
The Vandal
Member
Posts: 79
Joined: Fri Sep 16, 2022 7:43 pm
Location: West Sussex UK

Re: Lights, capacitors, action.

Post by The Vandal »

It was the hawker one that Spriddler and Dave16mct use.

Fitted it today and lights are working! Ammeter meh, maybe not though!

There was no movement from the needle when I connected the battery nor when turned the lights on without the engine running (sat slightly on + side of zero which seems to be it's resting position).

Checked the voltage across the terminals on tickover and was getting around 5.5v-6v, more like 6 when I blipped the throttle.

Went a wee burl on it to give the battery a bit of charge and once moving and going through the rev range properly the ammeter got a bit more active. Stayed up around +4 for most of the ride, switching lights on or off didn't seem to have much effect on it. The needle was definitely bouncing about a bit more than the other day when it seemed to have settled at 0 and then at full discharge during my ride.

Forgot to measure the voltage in the battery when I got it before going the wee run but when I got back it had 5.99v in it so that's positive. I think.

Do you all just leave the battery hooked up when your not using your bikes? I've pulled the leads off both terminals on mine while its not in use, I've had bikes in the past that have drained their batteries just sitting and with there not being any sort of ignition or anything that really 'breaks the circuit' on this bike I felt a bit funny leaving it hooked up.
The Vandal
Member
Posts: 79
Joined: Fri Sep 16, 2022 7:43 pm
Location: West Sussex UK

Re: Lights, capacitors, action.

Post by The Vandal »

Image

Wife and bike enjoying the sun and fresh air.
The Vandal
Member
Posts: 79
Joined: Fri Sep 16, 2022 7:43 pm
Location: West Sussex UK

Re: Lights, capacitors, action.

Post by The Vandal »

Having gotten another few rides in with the battery fitted, I'm really not sure everything is working correctly.

I used the bike to go to the post office yesterday and the lights were still going off when the revs dropped. They did this last week but seemed to get better once I got out of town and wasn't stopping and idling at traffic lights so much.

When I got back from the post office neither the lights nor horn were working with the engine off.

I disconnected the battery when I was done yesterday and measured the voltage in it this morning, just over 5v so a bit discharged.

I then plugged my meter into the battery terminals and started the bike up. That gave me around 4v at idle, rising to 7/7.5 when revving the engine.

This voltage coming from the dynamo seems to be correct and the lights working if I rev the engine suggests (to me at least) that the dynamo is generating power right?

Someone mentioned that it's not just the voltage coming from the dynamo that's important but also the wattage or current?

Is there a way for me to measure that with the meter below?

Image

I wonder if it's this modern looking Dyno Tec regulator that I have that's at fault. Is it that which would 'switch' from the dynamo powering the lights to the battery at low revs?
User avatar
jackstringer
Member
Posts: 321
Joined: Thu Oct 08, 2009 6:09 pm
Location: Somerset UK
Contact:

Re: Lights, capacitors, action.

Post by jackstringer »

W = V × A, A = W ÷ V, V = W ÷ A.

If you know the voltage and the expected wattage of the alternator then you can make a guess at the Amps. If it's less than 10A then you should be able to measure it with the meter you have. Just connect it in series, for example disconnect the lead from the battery and connect one end of the meter to the battery and the other to the lead you took off the battery.
Post Reply