Headlight drained the Battery

Here you can talk about all kind of TECH for the B50 B44 B25 And Other BSA unit Singles

Moderator: minetymenace

Post Reply
User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Headlight drained the Battery

Post by ArielDan » Wed Jan 28, 2015 5:58 pm

Whilst on my way to get the kickstand welded up and about 20 miles from home the B50 quit running at a really busy intersection. Fun. The bike has a brand new battery that I keep on a tender. Checked voltage, as I always do as a pre ride check, and it read 13.8. Good to go. I always leave the headlight on when running on the street. So after it conked out I pushed her to the side of the road contemplating my next move. After 5 minutes, tried a couple of kicks and she fired (no lights on for starting). Continued on to my destination without lights and back home with no problem..About 45 miles. So before I do my usual tearing everything apart, thought I would ask you good gentleman what might be the culprit? Thanks, Dan

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Wed Jan 28, 2015 6:52 pm

The alternator will put out 120W max. The headlight should use 48w to 55w depending on what bulb you have. The problem is that with the headlight on, you have used up all of the power in the battery and all of the power that the alternator can put out at the RPM you are running. This is pulling the voltage down enough that you no longer have enough power to fire the spark plug.
At this point you have already done part of the trouble shooting. The bike starts and runs with out the headlight, so you know the alternator is working. Next step is to find out where the main power drain is. I would next unhook the battery and start the bike up. Then I would turn on the head light. If it dies again then you now know the problem is in the head light/ switch or wiring. If it keeps on running then I would next start looking at the battery.
Jeff

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Wed Jan 28, 2015 7:05 pm

One thought. A long time ago I worked on a similar problem. The owner had done his own wiring and with the headlight on it would barely run, hit the brake and it would die. He was running a 48/48w bulb, 48w low beam and 48w high beam. The lucas bulbs are what they call a"pre-focus" bulb High beam is not so much a function of a higher output as it is the slightly different location of the high beam filament, that changes the focus. When you select high or low beam you are selecting a different filament in the bulb.
What he had done is wire the headlight so low beam was the low filament, but high was both the high and low filaments. So instead of 48w he was using 48w +48w =98w, in a system that would at max put out 120w.
Look for loose or corroded connectors, check the wires going into the bullet to be sure they are not broken or corroded. Dumb question but is the battery hooked up correct, postive ground. I bought a new Norton 850MKIII and the dealer had the battery in backwards. Hit the starter(kick assist) button and it would blow the fuse. Kick it and it would run.
Jeff

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7713
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 97 times
Flag: England
Contact:

Re: Headlight drained the Battery

Post by minetymenace » Wed Jan 28, 2015 7:16 pm

I have no problem running normal electrics and H4 headlamp. I doubt it is a fault with the wiring as you should blow a fuse, so my guess is either a coil down on the alternator or a diode open circuit in your rectifier. Assuming you have a wet cell battery, is there any water in it? Have you cooked the battery? Could be the regulator, global warming or lack of attention to the water level .....

A digital volt meter on the "diode" range (if not the ohms one) will test the rectifier.
With the bike running and revving (no headlamps) what is the voltage across the battery? Should be about 14v.
Got a cap in the circuit? If yes, once running will it run with no battery and no lights, will it run with no battery and lights?

Questions, questions......
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Wed Jan 28, 2015 7:55 pm

Wires that fray or start to break at a connector or where I see it a lot is where they come out of the molded plastic on the alternator stator have the effect of greatly reducing the wire size. I could pull a couple of old, used stators off the shelf that have plastic out cover hard and cracked at the spot where they come out of the molded stator. And normally you will see the wires themselves with many strands broken here.
Jeff

User avatar
kommando
>1400
>1400
Posts: 1970
Joined: Mon May 24, 2004 8:41 pm
Location: Scotland
Has thanked: 10 times
Been thanked: 52 times
Flag: Ireland

Re: Headlight drained the Battery

Post by kommando » Wed Jan 28, 2015 8:06 pm

Weak magnets on the alternator rotor is another one to look at.

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Wed Jan 28, 2015 8:16 pm

Here's what I know based on questions..
* Battery is 7 days old. Installed electrojuice myself, cooked overnight and topped off with distilled to top line. Present voltage not running 12.3.
* Positive earth, yes...Having wrenched brit bikes I really don't know anyother way :oops:
* Running voltage, no lights 12.5-12.9 @ 700 rpm (approx)
* Running voltage, key to #4 position, running lights only (no headlamp) 10.23
* Running voltage, headlamp on 6.15...Now I know why she quit
* Headlamp bulb 12v 45/40
* All wiring is original, at least by my tracing, no cuts, jumpers etc

Hope this helps...Thanks, Dan

User avatar
gunnag
>760
>760
Posts: 766
Joined: Fri Oct 01, 2004 9:32 am
Location: farnham surrey
Has thanked: 0
Been thanked: 3 times
Flag: Great Britain

Re: Headlight drained the Battery

Post by gunnag » Wed Jan 28, 2015 8:59 pm

A couple of things I would check using a decent volt meter :-
- taking each alternator output wire, test for continuity to earth, there should be none, if there is the stator is shorted
- test the resistance between each alternator output wire, I believe it should be something like 0.4 ohms
- test the AC voltage output from the alternator with the engine running at 3k rpm or so, I believe you should register at least 24v AC

It sounds like your alternator is low on output and the tests above should help verify this. Alternately, you may have a faulty rectifier and/or zenor diode, I guess the best test for these components would be to substitute for new.

beat
>1400
>1400
Posts: 5723
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 48 times
Flag: Switzerland

Re: Headlight drained the Battery

Post by beat » Wed Jan 28, 2015 9:12 pm

ArielDan wrote:* Running voltage, no lights 12.5-12.9 @ 700 rpm (approx)
* Running voltage, key to #4 position, running lights only (no headlamp) 10.23
* Running voltage, headlamp on 6.15...Now I know why she quit
bad Mainswitch , kontact points inside dirty ore loose
beat <201

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Wed Jan 28, 2015 10:16 pm

That voltage seems low. With lights off and revving the bike up does the voltage increase? I don't think that the Zener starts to regulate until ~13.5v.
Jeff

skippy
>1400
>1400
Posts: 1487
Joined: Mon Dec 19, 2011 3:25 am
Location: Horsham Vic Australia
Has thanked: 57 times
Been thanked: 14 times
Flag: Australia

Re: Headlight drained the Battery

Post by skippy » Wed Jan 28, 2015 10:29 pm

kommando wrote:* Running voltage, key to #4 position, running lights only (no headlamp) 10.23* Running voltage, headlamp on 6.15...Now I know why she quit
The battery should hold up the voltage even if the alternator is not working. sounds like both could be a problem.
Doug
Should never have sold them old motorbikes

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Wed Jan 28, 2015 10:39 pm

I was just looking at the B25/B50 owners handbook. You can unhook the main plug at the rear of the under the gas tank electrical box and run without lights. This is a good point to start checking from. I would take a voltage reading at the battery (-) and the ground, rev the bike a bit and see if it increases. Then I would unplug the main plug and repeat the test. This will help eliminate the lighting circuit as a problem. If you still have low voltage, I would then unhook the battery and tape off the leads and repeat the test. If you still have low voltage then I would dig into the aluminum electrical box and bypass the switch terminal 1 to terminal 2. If still low then you are down to a bad capacitor, zener, rectifier or alternator. Check the wiring bullets and connectors for corrosion, check where the wires go into the bullets. If they are the crimp on, then they can corrode and cause resistance. I am in Michigan and it is a little damper here so I am extra careful. If I use crimp on connectors, I dip the end of the wire in Copper anti-seize first and use heat shrink tubing. If I solder the connector, then I use Dielectric grease and heat shrink tubing. I also use dielectric grease on the push in connectors. Another good product is Fluid Film electrical protector spray. Good luck
Jeff

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Wed Jan 28, 2015 10:55 pm

ArielDan wrote:Here's what I know based on questions..
* Battery is 7 days old. Installed electrojuice myself, cooked overnight and topped off with distilled to top line. Present voltage not running 12.3.
Just rereading this. What kind of charger did you use. Hooked up over night is OK with a trickle charger, but a automotive charger can fry a motorcycle battery and boil off water in that time. I have seen many "auto" controlled chargers that were junk at controlling the amperage need!! I see you had to add water after charging, was it full before charging? It should be good after charging and not low. "Present voltage not running 12.3." Is this with the wires still hooked up. If it is, unhook them and take another reading. If it jumps up then you have a bad connection or device that is slowly draining the battery. 12.3v means the battery has a LOW charge in it.
I found this in a web search;
12.5 = 85% charged
12.4 = 65%
12.3 = 50%
12.2 = 35%
12.1 = drained
Jeff

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Thu Jan 29, 2015 1:01 am

Trickle charger Jeff...Will check with battery disconnected...Some clarification. When filling the battery I ran it to top line with go juice. It settled approx 1/16" after 24 hours. So just added a few drops to bring it to top mark. Kinda anal, I know...Thanks

Jeff K wrote:
ArielDan wrote:Here's what I know based on questions..
* Battery is 7 days old. Installed electrojuice myself, cooked overnight and topped off with distilled to top line. Present voltage not running 12.3.

Just rereading this. What kind of charger did you use. Hooked up over night is OK with a trickle charger, but a automotive charger can fry a motorcycle battery and boil off water in that time. I have seen many "auto" controlled chargers that were junk at controlling the amperage need!! I see you had to add water after charging, was it full before charging? It should be good after charging and not low. "Present voltage not running 12.3." Is this with the wires still hooked up. If it is, unhook them and take another reading. If it jumps up then you have a bad connection or device that is slowly draining the battery. 12.3v means the battery has a LOW charge in it.
I found this in a web search;
12.5 = 85% charged
12.4 = 65%
12.3 = 50%
12.2 = 35%
12.1 = drained
Jeff
Last edited by ArielDan on Thu Jan 29, 2015 1:09 am, edited 1 time in total.

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Thu Jan 29, 2015 1:03 am

Voltage does increase with revs and lights off. I just did a 20 second runup test, but it was increasing. With lights on it decreases...Dan
Jeff K wrote:That voltage seems low. With lights off and revving the bike up does the voltage increase? I don't think that the Zener starts to regulate until ~13.5v.
Jeff

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Thu Jan 29, 2015 1:06 am

Sounds like a good test gunnag...Will check that for sure...Thanks
gunnag wrote:A couple of things I would check using a decent volt meter :-
- taking each alternator output wire, test for continuity to earth, there should be none, if there is the stator is shorted
- test the resistance between each alternator output wire, I believe it should be something like 0.4 ohms
- test the AC voltage output from the alternator with the engine running at 3k rpm or so, I believe you should register at least 24v AC

It sounds like your alternator is low on output and the tests above should help verify this. Alternately, you may have a faulty rectifier and/or zenor diode, I guess the best test for these components would be to substitute for new.

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Thu Jan 29, 2015 3:11 am

Following your tips here is what I discovered.
* disconnected alternator, fired bike, solid +24/25 VAC...Nice...Lets keep going
*Pulled headlight off and checked switch. Sure enough one of the lugs wasn't screwed down. Reset and tightened both lugs.
* So I go to plug, after cleaning the bullets and connectors, I notice something odd. Both the grn/yl and wh/grn are sharing the same connector, meaning they are basically tied together. Checked the schematic and it shows each wire should go to each side of the rectifier, seperately. So I separated them and gave each it's own connection.
* Time for lift off. Fire the bike. No lights 12.9 and up to 13.2. Running lights, drops to 12.7 but climbs up to 12.9, nice. Headlight on drops to 12.3 but creeps up to 12.4 in my short test...
Tomorrow...Time to ride, lights on...Will let you know, going to bring my meter with me to check along the way.
Thanks gentlemen for your guidance...Dan

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Fri Jan 30, 2015 1:46 pm

I think we have a winner :thumb :thumb
Jeff

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7713
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 97 times
Flag: England
Contact:

Re: Headlight drained the Battery

Post by minetymenace » Fri Jan 30, 2015 3:46 pm

:ok <069 <200
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Fri Jan 30, 2015 5:25 pm

Went for a short hop yesterday. 50 miles. Left the battery on the tender overnight. Voltage at ride time was 13.6, nice. Time to ride, lights on. At mile 20 pull over to check. Uh O. Voltage is down to 10.6 :( . So I ask one of my buddies to tap the mystery electrical box. Hmmm, voltage is jumping everywhere. Ask him to jiggle key...Yikes, meter goes bonkers, can't get a solid reading. So we leave key alone and it settles at 12.4 positive charge, that's good. Bike is getting a tad hot so lets keep going. Finish our loop and check voltage again at the house...10.2. Well it's better than before. At least it didn't konk out. So an educated guess here would be the ignition switch is done? What do you think gentlemen?
BTW...First time owning a B50 and I have to say, this bike is a friggin ball to ride in the twisties. Compared to my B44, this bike is way more stable. Holds a better line when leaned over...Brakes could be better, but, like a flat track friend of mine says "brakes are for quitters" :laugh ...Good bar, seat setup, engine grunt and tranny ratio's makes for some great if questionably legal fun... :mrgreen:

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Fri Jan 30, 2015 6:28 pm

According to the wiring Diaphragm in the back of the owners manual. The ignition switch is the basic three terminal type. Position #1 is for power in from Battery and rectifier, brown /Blue wires and it also has the lead to the Zener attached, white/blue. Position #2 is the daytime output and goes to the oil pressure switch and the RH handle bar switch cluster. Position #3 is the nighttime position and is using the brown/green wires.
For testing purposes, you could bypass the switch and hook the wires from #1 to #2. Stopping the engine will get interesting though.
I have in the past, carefully pried back the crimps on the switch housing and taken it apart. Little springs and little inverted U shaped contacts that like to get lost. A good cleaning( grease gets old too), sand/polish the contact faces and re-lube with Dielectric grease and reassembly and crimp. Good to Go.
Jeff

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Fri Jan 30, 2015 7:37 pm

You're way more adventurous than I Jeff when it comes to taking little electrical components apart. Seeing as the ign switch is a the very depths of the housing unit, I ordered a new one (repro). Good time to bench test the zener, cap and rectifier and replace as necessary...As a few members have mentioned also a good time to clean all the bullets and receivers. Cheers, Dan

beat
>1400
>1400
Posts: 5723
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 48 times
Flag: Switzerland

Re: Headlight drained the Battery

Post by beat » Fri Jan 30, 2015 7:40 pm

beat wrote:bad Mainswitch , kontact points inside dirty ore loose
ArielDan wrote:the ignition switch is done?
Jeff K wrote:you could bypass the switch and hook the wires from #1 to #2
my vote....
and if you have a Voltmetr, fixating it on the tank top for easy reading, connecting it to the Zener and the Fraim and go for a next litle ride.....
beat <201

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Fri Jan 30, 2015 8:21 pm

Like that idea beat...Pretty sure that's why "duct tape" was invented :cool:

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7713
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 97 times
Flag: England
Contact:

Re: Headlight drained the Battery

Post by minetymenace » Fri Jan 30, 2015 10:14 pm

The charging circuit should NOT go through the ignition switch. If wanking the switch, stops it charging there is something wrong with the wiring of the switch (and possibly the switch as well, been through a few switches before I went for a lighter fob).

Look at it like this (good for +ve and -ve earth):
The alternator generates ac on two wires that feed the rectifier ac input.
The output from the rectifier feeds the battery and the Zener (which are in parrallel).
A wire is then taken from the non-earthed side of the rectifier/Zener/battery to the ignition switch.
The other side of the rectifier/Zener/battery is earthed

A faulty ignition switch may make the lights or ignition not work, but the battery should still charge if the engine is running (asuming fuses good).
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Fri Jan 30, 2015 11:05 pm

Looking at the wiring diagram. The Brown/blue wire from the rectifier, the Brown/Blue wire from the battery and the White/Blue wire from the Capacitor/Zener all meet at the ignition switch's #1 terminal. So if the alternator is charging properly and the battery has a full charge. Then something is using up a lot of power. It could be high resistance due to a bad or corroded connection or it could be a bad component. A lot of times when I find a overheated/ burnt wire, it can be traced back to a corroded connection or one with most of the wire strands broken. This resistance cause heat which compounds the problem. I like to systematically remove items from the circuit and test until I find the problem. I would connect the three wire from terminal #1 together and run a jumper to the - side of the ignition coil from here. Recheck voltage. If good then you know the problem is further down the circuit. If still low then I would remove the blue Capacitor and recheck. at this point you are left with the Zener, the Rectifier and the Stator.
If you are going to be replacing the switch, then you will be in the aluminum box. Good time to check bullets/connectors and wires. I like to use WD40 to clean the wires and then when I put it back together I like to use dielectric grease. Radio Shack, electrical parts store will have it. I order a small tub from HandA H*nda in California , http://www.handa-accessories.com/crvmaint02.html down towards the bottom of the page. H*nda brand Lithium Dielectric Grease.
Jeff

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7713
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 97 times
Flag: England
Contact:

Re: Headlight drained the Battery

Post by minetymenace » Sat Jan 31, 2015 1:49 am

Jeff K wrote: all meet at the ignition switch's #1 terminal
Thants where my money is!
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Sat Jan 31, 2015 2:39 am

Thanks gentlemen...New ign switch on the way. While I'm doing all this work in the rats nest of the electro module figured I might as well replace everything. zener, cap and recifier...Goo call of the dialectic grease Jeff...Also ordered...Will do surgery with pics when parts arrive..D

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7713
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 97 times
Flag: England
Contact:

Re: Headlight drained the Battery

Post by minetymenace » Sat Jan 31, 2015 2:48 pm

Zener should be good. You might want to replace the electrolytic dc cap, as they are supposed to have a finite life of 5 - 7 years, but they can last much longer (as they age, their capacitance reduces and the leakage current increases). The points condenser cap could be replaced as it is a low cost item, but I get the feeling that a new ones are not the best quality, so if it works, maybe don't fix it (unless you are making the worthwhile addition of electronic ignition, in which case you might want to fit a modern coil, then possibly add more cylinders, install up-side-down forks, up-rate the frame and suspension and rework the brakes. All depends on the depth of your pockets :???: ).
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

User avatar
ArielDan
>40
>40
Posts: 42
Joined: Sun Dec 14, 2014 4:57 pm
Location: Redwood City, California
Has thanked: 0
Been thanked: 0
Flag: United States of America

Re: Headlight drained the Battery

Post by ArielDan » Sat Jan 31, 2015 5:31 pm

Haha...I like the cylinder, frame and brake upgrade...Or I could just get one of these <215
10-DUCATI-SCRAMBLER-590x441.jpg

aminto
>60
>60
Posts: 60
Joined: Thu Jan 10, 2008 7:46 pm
Location: Perth, WA
Has thanked: 0
Been thanked: 0
Flag: Scotland

Re: Headlight drained the Battery

Post by aminto » Mon Jul 13, 2020 4:38 pm

Just to add to this tale -
I normally had my battery on trickle charge and checked each time before I went for a jaunt (usually better than 12.6V)- always upon return the battery voltage had dropped to around 10 - 11V - so an investigation began - the electrical box was taken apart (more than once) and each component checked and rechecked - as was the wiring (one or two dubious connections were re-soldered) - the alternator output was also good - and the battery passed load testing.
Everything seemed good but a current drain persisted when the bike was garaged... ...finally the 2MC capacitor was removed from its rubber housing to reveal goop seeping from its seams. So taking that out of the circuit and recharging the battery appeared to be the answer to my problem as the battery remained on 12.6V when garaged (and no current drain) BUT on the next jaunt the battery voltage again fell from 12.6 back to 11V.
The bike also refused to start occasionally when switched off in the middle of a jaunt due to low battery voltage.
Trawling this site for clues I found this topic and I began to count up the power being used by the bike - uprated headlight ('on' when riding) 55W + taillight 5W + stoplight 21W + flashers 42W + high intensity pilot bulb 23W intermittently totalling 146W ie way more than my stock alternator produces - so I reverted to the original 5W pilot light and hey presto the battery remained at 12.6V when garaged and has remained so even after a jaunt using all the electrics....
So my supposed safety feature of a brighter pilot bub had resulted in a great deal of frustration.
Andrew
1971 B50SS
1971 B25SS

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7713
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 97 times
Flag: England
Contact:

Re: Headlight drained the Battery

Post by minetymenace » Tue Jul 14, 2020 8:57 am

Glad you got it sorted, and thanks for the update...
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

User avatar
Ian Hingley
>1400
>1400
Posts: 2037
Joined: Sat Jun 30, 2007 2:50 pm
Location: Bristol, UK
Has thanked: 18 times
Been thanked: 13 times
Flag: Sao Tome & Principe

Re: Headlight drained the Battery

Post by Ian Hingley » Tue Jul 14, 2020 11:26 am

You can get high intensity but low current pilot lights for daytime running by converting to LEDs. Goffy does a range of them:

http://www.norbsa02.freeuk.com/

Cheers

Ian
66 BSA Victor Enduro, 72 BSA Lightning, 62 BSA B40 trials, 2015 Truimph Street Twin, 89 H*nda Bros 650, 2000 Aprilia Moto 6.5 Starck

Jeff K
>1300
>1300
Posts: 1347
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 23 times
Flag: United States of America

Re: Headlight drained the Battery

Post by Jeff K » Tue Jul 14, 2020 2:43 pm

And remember that the rated output of the alternator is at higher RPM's. Low speed around town driving with low rpm and the alternator is putting out lower then rated watts. You can also upgrade to a high output alternator like the 3 phase units or just replace the stator with a 200w unit for more power.
https://thebonnevilleshop.com/genuine-l ... 5-16-47239
Jeff

Post Reply