Aftermarket Voltage Guages

[anaxolotl]

Excited for another commute to work and already a bit late, i came out to a dead battery.  Turned over a couple times, then click click click.  

I believe the GEN telltale is working.. it is on when the ignition is on and at any time the RPM is under ~3k (hard to tell, the tach has a lot of bounce)... so, i'm guessing that my commute style is just one that doesnt adequately charge the battery and after a few weeks it just runs out... and i probably have a slow drain somewhere in the system... (at some point i'll ask for advice on how to find that).

i have a battery tender (which the battery (BMW, Exide Gel) is currently on) and i have no problem taking it out every month to top it off... if i know that the charge is low...

so.. i was considering installing a little voltmeter... anyone have any experience or thoughts on this?  I was considering this one based on the reviews and the fact that it is weatherproof: http://www.amazon.com/Kuryakyn-4218-Black-L-E-D-Battery/dp/B000GU5WNO/ref=pd_sim_auto_1

Any advice would be much appreciated.

[tvrla]

Before spending on extras, better get the charging system sorted.

The charge light should go out just past idle - around 1200 RPM.

There's something wrong with your alternator, maybe diodes, or voltage regulator.

Definitely get the battery charged up, but dig into the front cover. It's good to know what voltage the system is putting out with a volt meter or the LED light you linked to, but your charge light has been telling you it's not enough - at least below 3K. Get to know what the charge light has to say and it'll tell you a lot.

[steven m]

I recently installed a clock and voltmeter in my Wudo fairing, which needs to be, uh, painted.  Very easy install.  A used BMW voltmeter costs about the same as the one you are considering and you can still order the bracket from BMW.  Two wires, one from the green and black switched line and a brown ground.  Since I was installing a clock as well I ordered the factory wiring harness, yes, available new, reasonably priced, go figure, and the accessory gauges piggyback onto the connectors under the tach.  When idling in the dreaded traffic it falls just south of or is right at twelve volts but anything over 2500 rpm and it is a solid 14+, which was a surprise.  I don't have any tach bounce at all, so maybe that has something to do with your drain.  It's an electric tach, why would it be bouncing?

My clock is on all the time and I haven't had any battery problems, but now that I have said that it will probably be dead in the morning...

I'm sure Monte, master of the sano installation, has a lot more info than I do.

Steve

[Barry]

If you can find one a digital LCD voltmeter will be vastly more accurate than the BMW type or the LED one you are considering.

You are going to need an accurate voltmeter in any case to diagnose the charging system. When the battery is truly fully charged you can monitor the charge voltage at different revs. I can't stress enough that the battery should be fully charged or you will get misleading charge voltage readings. It should be around 12 volts at idle rising to a minimum of 13.8 volts at 3000 RPM. 14 volts is really desirable and slightly above is better still up to an absolute maximum of 14.5 volts. 14.3 volts is a good target If you do a lot of commuting as I do. Something like 13.8 volts would not be acceptable in this situation so I would consider an adjustable voltage regulator or a high output type which is set at this slightly higher voltage and this will help keep the batter charged on short runs.

My regulator is set at 14.5 volts cold falling to 14.3 volts as the engine warms up. Voltage regulators are designed to have this temperature gradient so be aware of that when you do the testing.


As has been said the charge light should go out just above idle (mine is out at idle) so if your voltages are not as indicated then there are problems somewhere with the voltage regulator or in the charging circuit.

[montmil]

Get your VOM out, start up the bike, raise the seat and after a warm-up, bring the revs up to about 4K and see what voltage is moving into the battery. Should be over 14 volts at those revs. If not, more investigation will be needed.

Did you mention the age of your battery?

[anaxolotl]

the battery tender is showing green and my multimeter doesn't seem to work anymore so a bit of the testing will have to wait.  The battery has a born on date of 01/09.
After i put it back in the bike, i'll see where the GEN light actually goes out at.  

I have no idea about the tach bounce.. aside from the work done in the shop, i haven't really tried fixing it up beyond a good cleaning and giving it back its stock longstem mirrors.  

I have a clymer manual sitting at home that i'll give a glance through to see if it has any ideas about tach bounce and hopefully by this weekend i can trouble shoot the electrical system.  

for commute context: after letting the bike warm up for a few minutes (mostly at full choke) i drive 8 miles in about 20-30 minutes with six or so stop sign/lights and an average moving speed of around 35.

[Bob_Roller]

The charging system really isn't doing much to charge your battery, it's barely providing enough power to run the electrical load when the bike is running .

I had the same problem when I lived in Chicago, 5-6 miles to work, 13 stop lights, the battery would get low enough, that if I didn't take the bike for a highway speed run once a week, or put a charger on it, by the middle of the second week the battery wouldn't turn the starter .

I'd keep your battery tender on the bike, whenever it's parked in the garage for the day .

If it's a serviceable type battery, you need to check the battery fluid level regularly, like every 2-3 weeks or so while on a battery tender, until you see what kind of loss you may get, you don't want the plates exposed, that's the worst thing for a storage battery .

[Barry]

Sounds to me that an 8 mile commute at 35 mph would run the battery down and need a regular top up charge once a week at the very least.

Another good test is if you start the week with a fully charged battery and measure the overnight  rested battery voltage on Saturday.

Assuming 80 deg F ambient :-

12.65 volts fully charged

12.45 volts 75% charged

12.25 volts 50% charged

12.0 volts 25% charged

If it's a VRLA AGM or Gell cell battery add 0.15 volts to those figures.

[Bob_Roller]

With my current commute to work, 12 miles, 1.5 miles surface streets 45 mph and two stop lights, 10.5 miles of 65 mph urban expressway, no battery charging problems in the last 19 years .

This is with all original charging system components and running two PIAA 40, 55 w H3 driving lights .

[Barry]

Not at all surprised Bob. That's a reasonably high average speed, little idling with only 2 stop lights and  10.5 miles at 65 MPH.

[anaxolotl]

So, i'm planning on doing the testing of my charging system this weekend but with this style of commute not changing in the foreseeable future, I am even more convinced i should install an inline voltmeter... and now i'm leaning towards a digital display.. does anyone have any recommendations?

Also, i've been glancing at motorrad electrik ever since the battery died on me.. would it be worth it to upgrade to their higher voltage regulator if the rest of the charging system checks out?  or do i really need to do something more significant if i am not a fan of taking the battery out to charge weekly. (unfortunately, i do not have a garage or an outlet near my parking spot... so removing the battery is going to be required)

[Bob_Roller]

You don't have too many options available for your situation .

I would email Rick Jones at Motorrad Elektrik and explain your situation to him, see if he thinks the high voltage regulator will help, I'm not so sure it will, due to the low engine speeds in your commute .

I don't know how secure your bike is at work, or at home, but there are solar battery chargers that put out 5 watts or so on a sunny day, that's just under .5 amps of charging .

I don't know if you get any Harbor Freight advertisements or not, but I know they have one or two solar chargers available .

http://www.harborfreight.com/automotive-motorcycle/battery/5-watt-solar-battery-charger-41144.html

With their usual 20% off coupons, it's around $48US plus tax .

[anaxolotl]

So, after an overnight and a day on the trickle charger, i put the battery back in the bike and she started up happily and i swear the telltales are unusually bright.

i did check where the GEN light was going off, and it seems to go off right around 1500 and then wont turn back on until around 1250 or just below... so... that sounds about in line with what i understood in the forum.  My multimeter isn't reading anything across terminals (nor any resistance when i check the probes against each other) so it looks like i need new probes before i do any more investigation.

Unfortunately, the apartment complex has something like 200 units and although i would call it safe, i dont know how long a solar panel would last  left unattended.  also, my bike is parked at work during most daylight hours, so maybe i'll just have to figure out a way to mount the panels on the bike itself

In the off chance that doesnt work.. it looks like I've gained the weekly activity of removing the battery for an indoor charge.

alas.

[Bob_Roller]

On your meter, when was the last time you replaced the battery or batteries ?

Also, if you can remove the back part of the meter, there should be a  fuse of some sort in there, usually a very low amp rating fuse, like .2 amps .

I think your charging system is in good working order, just our commute is not friendly to the charging system requirements .

[Barry]

Before you consider spending money on the charging system do the basic checks first. Then when you know the charging voltage that will be the time to make a decision. A high voltage regulator will help but it's likely you will still need to do some regular charging every week. I still have to unless the bike gets a longer run at weekend.

Were you taking the battery out to charge because you don't have a secure garage to park the bike and plug the charger in ?  
If so I can see how regular charging would be a bind.  I used a solar charger at home last year and it just about worked OK (until I dropped it) but you would get better results with more sun. I think a solar panel would be too big to mount on the bike though.

There are very expensive solutions like 400W high output alternators but I'd be trying everything else first.

As well as getting a little more out of your existing charging system with an adjustable or high output voltage regulator you could also come at it from the other direction by reducing the electrical load where possible with some LED replacement lamps. Every little helps.