Battery Life + more

[ells]

Hence, we need amp meters and volt meters. And, CheriAnn has one more reason she needs a Nomad, not that she needed any more...

[trip]

Originally Posted by Ells

Hence, we need amp meters and volt meters. And, CheriAnn has one more reason she needs a Nomad, not that she needed any more...

Here...here!

[waterman]

Originally Posted by Ells

CA, That was true when bikes had generators instead of alternators. The change over to alternators in cars occurred, well let's see if I can remember, mid 60's I seem to recall, or maybe somebody told me, yes that's it, so I was told. Bikes probably came later so depending what bikes you friend was talking about, he might have been correct, but not for yours.

Ells, I think you mentioned that you remember the days of hand crank starting your cars??

[waterman]

Most alternator systems max out their output somewhere around 2000 rpm. What you gain is relatively small after that. Running at idle you generally have 50 to 70 % of maximum output. Output is amperage or watts and not volts. That is the duty of the voltage regulator to convert the output of the alternator to about 13 V.

Idling with nothing on will charge the system. Everything relates to how much of a draw you put on the system.

Trip, even after a long haul ride and I know it is going to be awhile before I ride and put the battery tender on, it will charge for a short time period. Generally less than 30 seconds.

[ells]

What's all this talk about the bikes setting around and idling - RIDE the damn thing like there is no tomorrow and there will be no problem, until the end of the battery's natural life of course.

Waterman - those were hand-propped airplanes, they existed much later than hand-crank cars! :)

[macmac]

Well I disagree with Waterman respectfully, mainly the rpm range he stated is a bit low, but i would agree about 3,000 rpm is closing in on the upper limits.

The main thing is most alts and this counts cars must run at 2,800 rpm to just turn on.

This is easy on cars as most cars drive alts with a belt. The crank pully is about 3 times or more larger in diamter than the alt pully, and so at 800 engine rpm the alt is already 3 times faster and so ON.

Most bikes have a crank mounted alt less BMW which is belt driven, and so the alt runs 1:1 with the crank shaft.

Charging is regulated by what is turned on, lamps, coils, fuel pump, and battery condition at the time, plus wear and tear.

At the time means charging will be higher from a cold start, because a cold start has the most friction to over come with thicker oil conditions. That batter has just put out apx 360 amps in 2 or 3 seconds, while at the same time has powered up the ecu and related sencors, the coil the loss in the wiring, relays, and the above stated items.

On a volt meter you can see as normal as high as 15.2 volts sometimes.

Battery condition as wear and tear figures into any reading you can see in volts. A 6 year old battery may be worn and may not be able to hold the load of a battery less than 1 year old.

By 8 years most nomad batterys will be about used up and you can see these probably charge on a running engine at 15.+ all the time. When a battery that old and used up is on a bike and the bike is shut off, the bike might not start again, even though you saw 15.+ dcv as a reading.

A battery must be able to hold the charge and take a load to be of any use. You can charge a dead battery for so long as the alt will run and till it burns out trying to charge a dead battery.

I have seen charging sysyems fail an be all burned out, the alt is dead and the rec/reg is dead and for no other reason than it was used with a battery that would not take and hold a charge much less any load.

Volts is just one part of what is to be known, Amps is the other. With a volt meter and a Nomad after a cold start you will likely see 14.8dcv as soon as the engine runs.. If you had a Amp meter too, you might see 10 amps charging, maybe more.

Both readings will reduce if the battery is good, and has life. This depends on loads and the battery condition.

After riding and still at say 65 mph for over 1 hour, with only stock items on, a voltmetere might read 13.6 and up on a Nomad. If it had a amp meter it might well read 2 amp charge, as the alt creates the same charge, and the rec/reg waste the charge as heat, since th battery has all it wants, and only replaces a little the ecu, related items, lamps, pump, and etc need to run.

Other bikes will act this way, but are not near to what the charging system a Nomad has.

Other bikes which is most of them can and will run a battery down to not start with 1 hours worth of parking lot practice, typical of MSF course riding. The engine rpm isn't there enough and the bike IS running directly off the battery. Still a volt meter might read 13.5 or so, but that doesn't say a thing about amps..

I have another bike and it has a alternator. It will not run hi beam at 110 watts, and (2) passing lamps rated at 35 watts each sitting at a red light idling.

It has a like battery 18 Ah. That is 18 amp hours. In theory that means a good battery will run 1 amp 18 hours. It means it will run 18 amps 1 hour. It means it will blow out 360+ amps for a few moments in time, to turn on all the devices and still crank the start motor.

A car on the other hand has a battery rated to 650 cold cranking amps or more. All mine have 1,000 cca.

With out looking in the book I think ther Nomad has a Alt that max;s out at 30 amps... My old bike makes 20 amps max..

It is a rare day in the green grass where any alt makes max amps, and is a theory to engineers.

I deal in the real world and fix these things.. All of them.. with and with out brushes. I did it as a mechanic for nearly 30 years and I still do it now for myself and friends.. I think I have a good fix it rate as i haven't failed to fix on so long as i could get parts..

These days it is harder to get common parts like diode bridges and other parts used in alt and starters because i guess no one fixes them anymore. I needed bearings for the 65 amp alt on my old chevy 4x4. It was 27 bucks for them, and 17 for a new alt.. There was no question getting a new factory re-built alt was the way to go, but it was note worthy to find the bearings, the diode bridge, and brushes would have to be ordered!

I run a battery tender like charger called Shumaker. it has less bling as visable features than the Battery tender, but other wise is a auto charger. I use this any time I am not riding less the cooling off I allow parked so I don't burn my dainty fingers.

My bike off, the volt readings varry some depending on how fast I shut off the passin lamps which can be on any time I like engine or no engine, so I use a varable amount of amps, getting off, getting stuff out of the bags and getting my act together.

Most reading once everything is off are about 12.75 dcv. My battery is in good shape, and I might see reading with the lamps on which are 55 watts each, but no engine on as 11 dcv and even less if I take 20 minutes to set up a amp site after dark.

Since the battery is pretty good it will recover all by it self in time, so I can safely run the lamps to the point I can't start the bike that night, but it will recover and start by morning.

At home if I run the battery down that same way, when I hook up the charger I can see 13.30 instanly on the meter, because the charger makes 13.30 at 1.5 amps. and that's all this charger can do.

My old bike with just more or less stock lamps will run fine at idle, but hit the 35 watts lamps an it acts as if it is running out of gas. More over if these lamps are on the meter says it won't recover, with just rpm and I flip the switch off and it recovers to charge and i can use the lamps to the next red light. it would be easy to ride so slow as to drain the battery so the bike won't start untill long hours pasts and th battery had time to recover.

[macmac]

I am betting not mny will read that bit, and so going to the next step in the conversation would be a waste of time on my part.

That would be the field wire and the 1/2 battery voltage it uses to induce the stator/armature to be as much as 6 times battery voltage and ACV. Alternating Current.

[rksaw]

Originally Posted by Ells

And, CheriAnn has one more reason she needs a Nomad, not that she needed any more...

Reasons for getting a Nomad: 281
Reasons against getting a Nomad: 0
Riding a Nomad: Priceless

[rksaw]

Originally Posted by macmac

I am betting not many will read that bit...

Sorry Mac, but you're right. I saw that long post and didn't even attempt to read it. I'll probably replace my battery before the next riding season because I don't know how long it's been on the bike and I don't want to get stuck on the way to Custer in June.
Rich

[trip]

Originally Posted by rksaw

Sorry Mac, but you're right. I saw that long post and didn't even attempt to read it. I'll probably replace my battery before the next riding season because I don't know how long it's been on the bike and I don't want to get stuck on the way to Custer in June.
Rich

There's a lot to say for peace of mind, Rich. Carry on my man.

[waterman]

MacMac,

On an alternator output I will agree that it does go higher than 13 v. Have seen 15 volts but generally not for very long after startup. However, output of a alternator starts at a much lower rpm for the alternator then you stated. Found some graphs on auto alternator output (amps) vs shaft rpm. Most start at 1000 shaft rpm. At a 1:3 driver:driven ratio, which is pretty close to my pickup ratio, the rpm at idle of 8-1000 rpm would be a 2400 to 3000 rpm shaft rpm. Looking at the output graphs for 5 delco alternators, they put out about 60 to 70% of maximum amps at that rpm. At cruising speed of 60 in my truck, my rpms are about 1800. This would put the shaft rpms at 4,500 to 5000 which is giving about 95% of maximum output. These are by the test graphs. Yes there is little information on motorcycles but I can't see them varying from the automotive standards by much. I talked to a automotive engineer friend about this and he claims that they want 90 to 95% of maximum output at 60 mph. Going from 5,000 to 8,000 shaft rpm, you gain only 3 maybe 4 amps on a 78 amp alternator.

I did find some info on a Harley Ultra Classic Electra Glide. At idle or 1000 rpm, the output is 380 watts. At 3000 rpm, the output is 578 watts. Peak output is 598 watts. Output at idle is 63% of peak and at 3000 it is 96% of peak. Not to far off of the auto alternators. Cruising speed for the harley is 2200 rpm at 60. I wouldn't think that it would be to far off the 3000 rpm output.

Looked thru my old Rider magazines and found the C-14 review. Max output was at 5,000 rpm but cruising speed (60) was at 3,200. They must have decided to find the ultimate maximum of that alternator.

As far as idle output, they want the watts to be enough to handle everything that is stock and still slowly charge the battery. Normally if I have a dead battery, I boost it and then take a 10 minute drive to charge it if I don't have a charger available.

[macmac]

Waterman a bike is mounted at 1:1 and the big Vulcans have 2 alts and 2 rec regs.. with 18 diodes instead of 6. Vulcans are not the typical bike. Having 2 is redundant to a degree, and HEAVY, but vulcans are heavy so a few more pounds won't bother it.

You better hope it puts out that 15.2 or so after a drain and a cold start, It will reduce the amount of demands soon with a good system to 14.8, and lower still as needed to high 13's.

So a big vulcan has twice the stator most bikes have. Go check out a high reving sport bike, and you will find at low rpm it doesn't make much and at idle less. Try a Honda 250 Rebel, which has a bad time making enough to idle if left at low MSF training speeds too long.

The field wire is reduced dcv to apx 1/2 battery volts so say with the key ON when the field wire become first on, and no more has changed.. the field wire will be 1/2 battery voltage.. Lets say the battery is good, and standing has 12.8 dcv. That means the field wire will be almost 1/2, but with voltage drop in the wire and at the connector, so it is safe to say it will not be a dead match 1/2 or 6.4 dcv. It will vary to something less. That might be 6.3 dcv.

Then you press Start, the engine cranks over and fires up, and instantly the field wire gets more current when everything is correct. At idle you may see 13.6 dcv.. which means the battery sees a charge, and allows 6.8 dcv to the field wire thru the regulator. Then you rev the engine and excite the alt, which in turn via the rec/reg converts ACV to the field as 7.4 dcv, and you see 14.8 dcv.

By now you are moving over 1,000 engine rpm which is exactly alt rpm on a Nomad. So both charging systems are at work.

Other kinds of bikes will not work like this so easy. These other bikes making max 20 amps, will not truely make 20 amps in most cases, as lots of things matter and add up to voltage drop. You may have noticed temps will be mentioned in graphs, and that hotter temps, as ambient air temp, and also wire temp makes a difference. The hotter a wire the harder it is for current to flow.

This is easy to see by feeling most any relay. It should be cool to the touch, but most often after time it will be warm, and can sometimes be out right hot, and after that too hot to hold in the hand. That is voltage drop, and caused from a high resistance.

There is a whole other side to the system in ACV (alternating current) which is tapped off at the diodes and sent to ground as heat.

I use acv in diagnostics as well as Ohms with these systems. The ac sides varry depending on the make of the alt, as this acv comes from the stator armature, and can be measured as acv, with the system on. The rate per pair of stator wires on a induced system with no brushes will varry with as many pairs of wires from the stator as the stator has.

A typical 6 wire stator will make 36 volts in each pair of wires, at alt speeds of 2,800 rpm. Cut out 1/2 because it is acv, and you get 18dcv. Regulate that and add in voltage drop, and you get very close to 14.8 dcv.

When the good battery has been recharged as much as it can be, it demands not much more to remain where it is to run everything there is ON, and the regulator shunts to ground and wastes the current, untill there is again more demand.

You are correct in that after a given alt rpm it doesn't do much to make more, and it can't do more because the field wire is regulated, and excess is sent to ground, where there is a heat sink to take that excess off and cool the rec/reg.

Most of my problem was related to, too low of a alt start up rpm. Other wise the rest was very good.

MacMac, I read all of your posts. If I have an electrical problem I will just rent a trailer, trailer out to New Hamster( Tamworth), if I can find it, with a bottle/12 pack of your favorite beverage.

[rksaw]

Originally Posted by Trip

There's a lot to say for peace of mind, Rich. Carry on my man.

Definitely, I'm making a list of things that I have got to get done this winter...hopefully things will slow down here in about a month and I'll get to the battery and the final drive oil and put in some Iridium Spark Plugs and ... the list goes on. Great reading here and lots of great advice from people who definitely know what they are doing. I think it's time for a road trip to Cadd's and BD's and Mac's place...what do you think?

[macmac]

Originally Posted by meanstreak031

MacMac, I read all of your posts. If I have an electrical problem I will just rent a trailer, trailer out to New Hamster( Tamworth), if I can find it, with a bottle/12 pack of your favorite beverage.

Yer on.. Free camping in a nice field too. All woods around it, no traffic either. Some of the best ridin anywhere, and all scenic.

Wiring and electrical is boring for those who don't do it much. When it fails, it can be a nightmare. I did it to get paid, so for a long time it has been just another thing I do, and I seem to do it well.