Topic: Charging and Urban Myths

[SteveD CB500F]

Is it true that the alternator is switched to provide more power when the lights are on?

I've often wondered as my 500 seems to go slowely flat when I run it during daylight with the headlight on. With every other bike on the road running like this I often tell myself that "these old bikes were never meant to be run with the lights on 24/7"

Should I keep charging overnight once per week or is there something else wrong with my charging system? (Battery is new - everything else is 32 years old!)

[carsholduptraffic]

no its not true. the alternator just makes the juice regardless of whats happening. the juice goes to the rectifer first where it gets the seeds and stuff taken out (3 yellow wires go in (ac three phase) and dc comes out). this fresh juice is watched by the regulator which has its hand on the tap that controls how much juice the alternator produces. it does this by feeding a little bit of the fresh juice back to the hamsters that run around in the rotor on the left side of the motor, the more they get, the slower they run, and less juice gets made.
the regulator needs to be adjusted sometimes. if your lights are getting dimmer over riding time, then not enough juice is getting made to chage the battery, or (more likely) the battery is stuffed.
check the regulator, get a new battery, and be nice to the hamsters.

[SteveD CB500F]

So its actually the regulator that carries out this chore... Do I understand correctly (hamsters or not) that the additional load of running with lights should be compensated by the regulator and that the battery should still charge?

The battery is 3 years old and I do about 1000 miles per year.

[Glenn Stauffer]

This is the charging rate table for the CB750.  I don't have specific information for the CB550.

http://sohc4.us/?q=node/62

You can measure voltage at the battery terminals at different RPMS to see if your charging system is doing its part.

[eldar]

Well what should happen is that, as the motor spins it will produce a certain amount of output at the generator. As the motor spins faster the gen puts out more. Thats where the regulator comes in. It controls the field and thus the amount of output from the gen. If the reg is not adjusted properly, it will not control the gen as it should. This can lead to too much output or not enough.

[carsholduptraffic]

the regulator is the 'brains' of the altenator (hamster controller). the cb750 (i'm not a 500 expert) has the same sort of power system as a garden variety car of the era, but it's alternator bits are more spread out.
the heart of the  system is the battery. everything runs off that. the role of the alternator is to charge the battery and thats it.
if the battery is expending more energy going out than is coming in then things will get dimmer over time, and the alternator will be working hard to maintain the battery.
the regulator is controlled by voltage. all connections must be tip-top. the rectifier gets hot, keep it clean, and get it checked for a blown diode. that will do weird things.
the rotor is the wavy basket thing on the crank. those waves do magnetic magic on the stator coils outside them, when energised by the feild coils inside them. stators makes the juice, the fields controls it. up to a point that is, as the whole deal makes more volts the faster it spins. thats where the regulator (hamster controller) comes in, and it is an old school switching relay type. it switches on and off with rising volts (revs) in the 1500 to 3000 range from (suspect) memory.
too low (in revs) regulator cutoff beats up the rectifier, too high cutoff cooks the battery due to high voltage.

[bryanj]

Regulator gives only 3 levels of charge
(1) No charge
(2) Approx half charge
(3) Full charge

One of the contacts "vibrates" between either 1 & 2 or 2 & 3 or sits on 3 if required and occasionally it can "stick" wherever it feels like.

A better charging rate can be obtained by using a DOHC reg or building an electronic one as per the info on a members site (sorry whoever i forgit again!)

[333]

Hamsters?  Is this something that 350Fs didn't come with, but larger displacement bikes had, or are these aftermarket hamsters?

Seriously, are you running the stock headlight?  Upgrading to a H4 55/60 will draw considerably more current, and will draw your battery down faster.  One of my buddies gets erked that I don't ride w/headlights on during daytime.

Maybe I need bigger hamsters.

[Partsbiker]

I hate to sound like a doomsayer but, being in the automotive business for 10+ years, I have learned that statistically speaking, batteries are only good up to a minimum of 3 years.
After about 3 years its anyone's guess as to when any given battery will weaken and decide to give up the ghost.
This is even true for the name brand batteries that come with 5-year warranties. I cant tell you how many batteries ive replaced seeing them being just a few months over the 3 year mark.
This is not to say yours is bad, I've seen batteries go on for 7 years, but very very few.
All I'm saying is that is you should have your battery load tested and hydrometered.

[TwoTired]

I've always felt that the voltage regulator on the bike was mis-named.  While it makes its decisions based on voltage present on the black (switched 12V) distribution system, its true function is to simply keep the battery from overcharging.  The battery voltage dominates the bike's electrical systems.  And, the regulator/alternator tries to keep the battery fully charged.  The alternator's job is complicated by the fact that it has a variable output based on engine RPM and it makes about 1/3 of its capability at the engine's idle speed.

With all the lights on, the power draw does exceed the alternator production at idle.  Thus with all the lighting on and a steady diet of idle RPM the battery will slowly deplete...on a good day. (more about this later)  

The early bikes had a headlight switch.  And, I can only assume that driving at night was considered an aberation by Honda engineers.  The CB500/550 can just maintain a full battery under all engine RPMs with the lighting off, but not on.  It wasn't unil the mid 70's that legislation forced headlights on at all times.

Now let's go back into the time machine from the good old days to the present's bad new days, where time and the elements have taken their toll on things mechanical.  The alternator in these bike is battery excited.  And, the strength of their output is related to the energy fed to them.  There are a lot of switches and connectors in the electrical path between battery and alternator field.  The reduction in voltage caused by losses in these connectors is directly related to the alternator reduction in output capability.  Even a 10 percent loss is significant and can make the difference of maintaining the battery, or not, at idle and with lighting... OFF!  Then, of course, even with the alternator spinning at peak production RPM, it provides less replenishment for the battery, as well.

So, if you think your bike maintains a dim outlook on life, see if the battery can still get the alternator really excited with full voltage on the "regulator's" (shudder) black and white wires.  Measure there and local green.  Then compare that with what you get at the battery terminals.  Derate your alternator capabilty by at least the ratio of voltage supplied to lost over the electrical distance.

I won't even mention the speed and agility ratings of 30 year old hamsters, even if they still have magnetic personalities.

Cheers,

[dusterdude]

I hate to sound like a doomsayer but, being in the automotive business for 10+ years, I have learned that statistically speaking, batteries are only good up to a minimum of 3 years.
After about 3 years its anyone's guess as to when any given battery will weaken and decide to give up the ghost.
This is even true for the name brand batteries that come with 5-year warranties. I cant tell you how many batteries ive replaced seeing them being just a few months over the 3 year mark.
This is not to say yours is bad, I've seen batteries go on for 7 years, but very very few.
All I'm saying is that is you should have your battery load tested and hydrometered.

true,and your lucky on a bike battery to get one year out of them.i will say however the one i have is about 2 years old,so i better knock on wood.

[TwoTired]

I had to replace the battery last week in a 90 Mazda I inherited from my Mother-In-Law.  She kept maintenence records of all service to the vehicle.  There was also the reciept from Wal Mart for the battery, now failed, dated October 1997.    The numbers on receipt and battery matched.  Ten years!

Wish I could have gotten another just like it.

Cheers,

[crazypj]

I thought regulator switched power to the field coils to maintain voltage on these bikes? ('monitors' battery voltage and opens and closes contactors)
Mechanical regulators can only switch at around 60 cycles per second (or thereabouts) the constant voltage spikes are generally not good for battery.
Electronic regulators 'switch' around 200 cycles per second.
With centre tap alternators (Yamaha, Suzuki, BMW) they 'switch at 600+cycles per second,
 May not be a bad idea to check contacts and settings
 There is only so much you can get out of the generator no matter how fast you spin it. really you need to work out the total amp draw and make sure your not exceeding it.  (Ahh, remember Lucas? )
 If you have a 55/60 headlight bulb (around 5amps@12volt main beam), plus coil draw, (about another 5 amps total) plus tail light, idiot lights and voltage drops through old connectors you probably get very close to or exceed the max capabilities of system
At only 1000 miles a year it should be left on a trickle charger most of the time in my opinion, the hamsters probably starved to death
 On batteries, I had to replace a 3 yr old battery on Mazda B2300 pickup, battery design has improved to the point where it can fail withing a few months of acceptable design life. For years automotive trade has relied on built in obsolescence to stay alive.
Thread hijack,
There was a documentary about John Deere tractors, they almost went bankrupt because they were lasting too long, average design life was 22 yrs, cut it to 10 and people were OK with buying a new tractor, repair parts available but repairing old wasn't as efficient as buying new for major items.
 Orwell was probably about 50 yrs off, but the corporations are going to run everything eventually (we already have cameras in public places for our safety, business probably running governments, protecting overseas investments, etc)
 
PJ

[333]

I second what Partsbiker said.  Your lucky to get 3 years out of a battery.  2 things you can do to better your chances of making 3 years.  Ride it year 'round or use a battery tender, and having worked a cycle parts counter, I recommend a Yuasa.

[crazypj]

I second what Partsbiker said.  Your lucky to get 3 years out of a battery.  2 things you can do to better your chances of making 3 years.  Ride it year 'round or use a battery tender, and having worked a cycle parts counter, I recommend a Yuasa.

 Proves my point, 3 yrs is now acceptable
 Think Green 
PJ

[vames]

This guy selling solid state "voltage regulators" claims you can get much better charging at idle. Anybody have any experience with these?


http://cm.ebay.com/cm/ck/1065-29392-2357-0?uid=8842264&site=0&ver=EOIBSA080805&lk=URL&Item=320136744703

[Partsbiker]

Just to be safe, head on down to your local WallyWorld (on second thought-Are there any wallyworlds in the UK?) and just fork out about 40 bucks to get yourself a new battery. To me that type of insurance is cheap, plus a weak battery can have adverse effects on your starter and alternator. Ive seen alts burn themselves out just trying to keep up with a weak battery that wont take a good charge.

[CrisPDuk]

I had to replace the battery last week in a 90 Mazda I inherited from my Mother-In-Law.  She kept maintenence records of all service to the vehicle.  There was also the reciept from Wal Mart for the battery, now failed, dated October 1997.    The numbers on receipt and battery matched.  Ten years!

Wish I could have gotten another just like it.

Cheers,

I can beat that TT

My '94 Subaru Legacy's first battery finally gave up the ghost last Christmas, and I think it was me that killed it, rather than old age   Because it ceased being my main car, I was leaving it parked up for weeks at a time with the alarm armed

I've not saved any money though, because my '86 Ford Sierra has never managed to make a battery last more than two years in the 12+ years that I've owned it

[kslrr]

How's this CrisPDuk?  At a railway museum in Perris, CA, we have nursed back to health 30 year old batteries for diesel/electric engines using a very large type of battery tender that breaks down the calcification.  These things are 6 to 12 volts and weight up to 300 pounds.

[Jonesy]

For a few bikes, Steve's thought does hold true. In the Honda CA95 (C95 for the Brits  It uses a permanent magnet alternator that runs with no regulator. The alternator has two output wires that run to the ignition switch (the switch also controls the headlight). In the "Day" running position where the headlight is off, only one half of the alternator is used to charge the battery. In the "Night" running mode when the headlight is on, both halves of the alternator are connected to the battery, doubling the output.

[TwoTired]

How's this CrisPDuk?  At a railway museum in Perris, CA, we have nursed back to health 30 year old batteries for diesel/electric engines using a very large type of battery tender that breaks down the calcification.  These things are 6 to 12 volts and weight up to 300 pounds.

I was going to mention something similar.  I was at the Western Pacific Railroad Museum many years ago.  And, they were restoring to service a diesel locomotive they got as surplus from the US Navy.  It was still battleship grey and USN markings.  They had it running and charging up it's original battery from when the Loco was first produced in 1954-ish. I visited there in the early 90s, so the battery was about 50 years old.  I said that it was pretty amazing that the battery was still good.  The maintenence guys there said it was quite routine for the battery to last that long and quite longer. 

If they applied that same technology to the automotive industry, can you imagine how much money would be lost in taxes, dealer fees, transportation fees and taxes, manufacturing wages & income taxes, and recuring manufacturing costs.  An entire sub economy would be lost as governmental and industry income, and the harnesses on millions of consumers would be slipped.

Can't have that!

[edbikerii]

So, what is the secret technology that allows these railroad batteries to be re-used?  Is it within the batteries themselves, or is it a special technique for rejuvenating them, or both?

I've got a buddy with a GoldWing whose battery won't hold a charge.  He doesn't need to pay $100 for a new one (besides, he owes me money).  Any suggestions on rejuvenation?  He's got nothing to lose.

[csendker]

These things are 6 to 12 volts and weight up to 300 pounds.

Have your buddy strap one of these bad-boys on his 'wing.

Seriously, just to add to the mix here, this is the charging output I have for 550's:

RPM - Volts - Day Amps - Night Amps
1,000 - 12.0 - 6.5 - 2/3
2,000 - 12.4 - 0 - 1
3,000 - 13.2 - 2.4 - 1
4,000 - 14.5 - 1.3 - 1
5,000 - 14.5 - 1.0 - 1
6,000 - 14.5 - 1.0 - 1
7,000 - 14.5 - 0.8 - 1
8,000 - 14.5 - 0.6 - 1

The 1,000 amp numbers confuse me.

Anyway, do I have this correct?:

Obviously, you're not going to charge a 12V battery until you go over ~2,000 RPM and get the output voltage up high enough.  Voltage is pressure so you need a higher input pressure/voltage so you can stuff the amps into the battery.  Then, you have to do a power draw calculation to see if there's enough current available to power the bike and leave some left to charge the battery.  But actually, you power the bike from the battery, so I guess it more appropriate to say you need more amps going into the battery than going out of the battery.  If you do charge the battery (regulator output will be at 14.5 there), the battery voltage will begin to rise.  When it gets high enough, the regulator 'switches' the output voltage back down to 12V or so and be in a 'maintenance' mode of sorts.  If you suck more power out of the battery than into the battery, the battery voltage will slowly fade into oblivion.  The engine, lights, etc draw the power, but so does a crappy wiring harness (resistance = power draw).  Cleaning up the harness will reduce the draw.  LED's will also reduce the draw (assuming you change the ones that are always lit).  Halogens will increase the draw.  You win some and you lose some.

[nickjtc]

I gree with whoever said...ride the bike and whenever it's laid up for any period of time put the battery on a motorcycle specific charger/tender. I use a Battery Tender myself. The VFR I had for five years (90,000km) still had the original battery when I sold it, and it was still going strong.

[TwoTired]

The 1,000 amp numbers confuse me.

That's because of a polarity sign omission.

A 12 v battery is fully charged at 12.6 V.  If you read 12 V, why is it low?   Might depeletion mode have something to do with it?

Cheers,