Resend my activation email : Register : Log in 
BCF: Bike Chat Forums


Motorcycle Battery - How Many Amps on 6 Volts?

Reply to topic
Bike Chat Forums Index -> The Workshop
View previous topic : View next topic  
Author Message

Calaenall
L Plate Warrior



Joined: 19 Apr 2019
Karma :

PostPosted: 06:00 - 20 Apr 2019    Post subject: Motorcycle Battery - How Many Amps on 6 Volts? Reply with quote

I am doing a bit of research on possible replacement battery for my 1948 Panhead. I can get a genuine Harley 6 volt battery, a nice reproduction of the original wet cell 6 volt battery, or a new high tech sealed one.

One questions is how many amps is best for me and why?

I am inclined to trying a sealed gel battery as I prefer not to have to check and top off the cells or clean the corrosion if I don't need to.

I have found some rated at 14 amps and others at 18 amps. Is there a significant value to one over the other?
 Back to top
View user's profile Send private message Visit poster's website You must be logged in to rate posts

Nobby the Bastard
World Chat Champion



Joined: 16 Aug 2013
Karma :

PostPosted: 11:21 - 20 Apr 2019    Post subject: Reply with quote

If your bike will never pull as much as 14 amps, you are wasting money spending more on an 18 amp one, but an 18 amp one won't hurt it. The bike will pull the same amps out regardless.

Why spend extra on a hd branded one? There are better batteries available for a lot less.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint 1050 ST
 Back to top
View user's profile Send private message You must be logged in to rate posts

RhynoCZ
Super Spammer



Joined: 09 Mar 2012
Karma :

PostPosted: 11:31 - 20 Apr 2019    Post subject: Reply with quote

If your motorcycle is kick start only, then there's no point in getting higher capacity battery.

I do prefer the modern sealed batteries, though. There are some very tiny and light sealed batteries on the market. I even got one for the MZ, that I ride.
____________________
'96 Kawasaki ZX7R P1 (sold) - '90 Honda CB-1 (sold) - '88 Kawasaki GPz550 (sold) - '87 Honda XBR 500
'95 Mercedes-Benz w202 C200 CGI; At my disposal: MZ 150 ETZ
 Back to top
View user's profile Send private message You must be logged in to rate posts

WD Forte
World Chat Champion



Joined: 17 Jun 2010
Karma :

PostPosted: 15:20 - 20 Apr 2019    Post subject: Reply with quote

As above, a 14A will do.

Just had a google out of curiosity and the stock generator only puts out
13A max on a good day, ie 11-13A at 3000 rpm which drops as engine speed rises
so if we're optimistic, we can say you have a 78 watt max generator/dynamo

I reckon 6V led bulbs would be a better investment than a bigger capacity battery
as light outputis about 5 times more per watt
____________________
1979 CX500 - Zanussi Wd12: - LG Combi Multiwave - Swan 4 slice toaster with removable crumb tray
 Back to top
View user's profile Send private message You must be logged in to rate posts

Triton Thrasher
Could Be A Chat Bot



Joined: 16 Oct 2012
Karma :

PostPosted: 17:53 - 20 Apr 2019    Post subject: Reply with quote

Itís amp hours, lads.

Any 6V motorbike battery that looks about the right size will do.
____________________
Rrrrrrrrrrrrrrrrrr
 Back to top
View user's profile Send private message You must be logged in to rate posts

stinkwheel
Bovine Proctologist



Joined: 12 Jul 2004
Karma :

PostPosted: 18:06 - 20 Apr 2019    Post subject: Reply with quote

Gel batteries are becoming old hat (ansd hard to come by) unless you specifically need to mount it upside down. Get a decent glass matt absorbtion type.

If the battery is on display, what the BSA guys used to do (and probably still do) is carefully wash out their original lucas battery with the rubber casing, Cut/wiggle/pry the top off it (careful, gloves and goggles!), rinse it out some more and remove all the lead plates. They then find a modern AGM battery that fits inside it (which will be a lot smaller for the same output) and connect the terminals up internally. Silicone the top back on and you've got an authentic looking battery with modern internals.

Can you convert it to 12v though?

Some bikes you can simply do this by re-jigging some of the internal wiring in the mag/dynamo/whatever and fitting a different zennnor.

It's a common modification with old 6V royal enfields. A 12v system needs half the current for the same wattage bulb. So all the switches and wires are be twice as thick as they need to be.

What WD Forte says about LED lamps is also true. The bike I just built draws 2.2A total. With the headlamp on full beam, brake light and flashers on. So my fag packet sized battery will run the electrics for 2 hours with all the lights on. I even have an LED headlight bulb and it's entirely adequate (once I get the headlamp pointing in the right direction).

They are even starting to bring out ones suitable for AC systems and positive earths.
____________________
ďRule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.Ē
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.
 Back to top
View user's profile Send private message You must be logged in to rate posts

Triton Thrasher
Could Be A Chat Bot



Joined: 16 Oct 2012
Karma :

PostPosted: 18:52 - 20 Apr 2019    Post subject: Reply with quote

12V conversion is possible. Regulators are on the market for just that.
http://www.dynamoregulators.com/dvr2.php

Converting an old Enfield with a 6V alternator to 12V is all good, but such an old Harley wonít have an alternator.

If you regulate a 6V dynamo (DC generator) to 12V, it will require more rpm before it starts charging. That can mean your battery goes flat in slow traffic.
____________________
Rrrrrrrrrrrrrrrrrr
 Back to top
View user's profile Send private message You must be logged in to rate posts

RhynoCZ
Super Spammer



Joined: 09 Mar 2012
Karma :

PostPosted: 00:11 - 21 Apr 2019    Post subject: Reply with quote

Triton Thrasher wrote:
If you regulate a 6V dynamo (DC generator) to 12V, it will require more rpm before it starts charging. That can mean your battery goes flat in slow traffic.

It's not as quick as you'd think. Even with the lights on, you may still do tens of miles before the voltage drops too low for the ignition to work. Well, that might not be true with modern ''computerised'' motorcycles, that are voltage sensitive.

I did maybe 50 miles with no charging, the lights on on the CB-1 and I did use the electric starter (4 cylinder engine, single H4 bulb headlight + tail light and all the tiny bulbs in the gauge cluster).

Also, many older bikes with dynamo do not charge the battery on idle and at low revs. I even think that race bikes don't normally have any alternator/charging system. When it comes to racing, every kW counts and alternators do ''rob'' you of some engine power. Thinking
____________________
'96 Kawasaki ZX7R P1 (sold) - '90 Honda CB-1 (sold) - '88 Kawasaki GPz550 (sold) - '87 Honda XBR 500
'95 Mercedes-Benz w202 C200 CGI; At my disposal: MZ 150 ETZ
 Back to top
View user's profile Send private message You must be logged in to rate posts

Triton Thrasher
Could Be A Chat Bot



Joined: 16 Oct 2012
Karma :

PostPosted: 10:06 - 21 Apr 2019    Post subject: Reply with quote

RhynoCZ wrote:
Triton Thrasher wrote:
If you regulate a 6V dynamo (DC generator) to 12V, it will require more rpm before it starts charging. That can mean your battery goes flat in slow traffic.

It's not as quick as you'd think. Even with the lights on, you may still do tens of miles before the voltage drops too low for the ignition to work. Well, that might not be true with modern ''computerised'' motorcycles, that are voltage sensitive.

I did maybe 50 miles with no charging, the lights on on the CB-1 and I did use the electric starter (4 cylinder engine, single H4 bulb headlight + tail light and all the tiny bulbs in the gauge cluster).

Also, many older bikes with dynamo do not charge the battery on idle and at low revs. I even think that race bikes don't normally have any alternator/charging system. When it comes to racing, every kW counts and alternators do ''rob'' you of some engine power. Thinking


I donít have your experience, having never owned your nice little Honda, but I have used a motorbike with a 6 volt dynamo regulated to 12 V, so I donít have to ďthinkĒ how it behaves.

If it commenced to generate at 1,100 rpm when running at 6 V, it would commence to generate 12 V at 2,200 rpm. It would not balance the load of a 12 V headlight until well over 3,000 rpm.

I could not use the headlight within 30 mph limits, simple as that. It was necessary to have a 10 watt halogen pilot bulb for going through towns. Nowadays a bright LED would be more sensible. Practically everyone who has done the 12 V conversion to a 6 V DC generator (called a dynamo in the Uk) has the same sort of issue. Some liars claim they havenít, because theyíre never wrong; some people never ride in slow traffic at night.

It doesnít matter all that much with magneto ignition, because a flat battery doesnít stop the engine. It doesnít matter terribly much with points and coil, because the engine will run with a very low battery and you get a bit of warning. It will cause roadside failures with electronic ignition.

You may get 50 miles from a well charged battery, with no charging system, but if youíve been riding in various conditions for a few hours with the converted dynamo system, youíre often not starting with a fully charged battery when you enter a town.
____________________
Rrrrrrrrrrrrrrrrrr
 Back to top
View user's profile Send private message You must be logged in to rate posts

Riejufixing
World Chat Champion



Joined: 24 Jun 2018
Karma :

PostPosted: 12:02 - 21 Apr 2019    Post subject: Reply with quote

Triton Thrasher wrote:
12V conversion is possible. Regulators are on the market for just that.
http://www.dynamoregulators.com/dvr2.php

Converting an old Enfield with a 6V alternator to 12V is all good, but such an old Harley wonít have an alternator.

If you regulate a 6V dynamo (DC generator) to 12V, it will require more rpm before it starts charging. That can mean your battery goes flat in slow traffic.


Quite right about the "alternator", & RPM. You can have your dynamo armature rewound, but it's an expensive process (for instance, see here: http://www.dynamoregulatorconversions.com/6-to-12v-conversion.php ).

With your 6v normal cheap conversion you basically double the power of the generator, and it makes a very big difference going from a 6v30/24W headlamp to a "modern" 60/55W one. I had a conversion on an old Russian bike, and it was fantastic.
 Back to top
View user's profile Send private message You must be logged in to rate posts

Triton Thrasher
Could Be A Chat Bot



Joined: 16 Oct 2012
Karma :

PostPosted: 13:08 - 21 Apr 2019    Post subject: Reply with quote

Yes, an armature wound with more turns of finer wire is better suited to 12 V at lower rpm, but there are warnings about fragility. I havenít tried one.
____________________
Rrrrrrrrrrrrrrrrrr
 Back to top
View user's profile Send private message You must be logged in to rate posts

Riejufixing
World Chat Champion



Joined: 24 Jun 2018
Karma :

PostPosted: 18:37 - 21 Apr 2019    Post subject: Reply with quote

Triton Thrasher wrote:
Yes, an armature wound with more turns of finer wire is better suited to 12 V at lower rpm, but there are warnings about fragility. I havenít tried one.


IKWYM. The expense!

"Triton thrasher". I've got a Triton. Are you a mine of information?
 Back to top
View user's profile Send private message You must be logged in to rate posts

Triton Thrasher
Could Be A Chat Bot



Joined: 16 Oct 2012
Karma :

PostPosted: 19:26 - 21 Apr 2019    Post subject: Reply with quote

Riejufixing wrote:
Triton Thrasher wrote:
Yes, an armature wound with more turns of finer wire is better suited to 12 V at lower rpm, but there are warnings about fragility. I havenít tried one.


IKWYM. The expense!

"Triton thrasher". I've got a Triton. Are you a mine of information?


I am renowned as a minefield of useless information.
____________________
Rrrrrrrrrrrrrrrrrr
 Back to top
View user's profile Send private message You must be logged in to rate posts
Display posts from previous:   

Post new topic   Reply to topic    Bike Chat Forums Index -> The Workshop All times are GMT + 1 Hour
Page 1 of 1

 
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum

Read the Terms of Use! - Powered by phpBB © phpBB Group
 

Debug Mode: ON - Server: discovery (www) - Page Generation Time: 0.16 Sec - Server Load: 2.25 - MySQL Queries: 16 - CDN Objects: 37 - Page Size: 84.23 Kb