[align=center]Battery Problems... Keep Going Flat?[/align]
It's worth paying a bit of attention to keeping the battery in good condition... a bad battery effects performance. Just ask someone that got a new battery recently!
How do you know its going flat or not performing?
A battery in good condition and charged will quickly crank the bike and start it. If it's low on charge, you'll hear the starter motor rotate a bit slower and take longer to spin up to speed, and in the dark you'll notice the headlights dip a lot while cranking. Lower again, and although the bike still cranks over it won't fire up. This is because the voltage has dropped so low, that the spark plugs won't fire with a hot enough spark. Turning the headlights off (or pulling the headlight fuse if you don't have a switch) might be enough to get you started. Usually you can still roll start the bike. Even lower again, and you'll get this rapid clicking noise from under the seat, and the starter motor won't turn over. Even lower, and you have no chance of roll starting, as the battery will suck all the juice
BTW... that clicking is the starter relay, which switches on to power the starter motor, then the starter motor loads the battery up and the relay no longer has enough power. So it turns off again hahaha.... Hence it repeats, on-off-on-off...
A battery typically goes flat under the following conditions...
1. Old battery
2. Mis-treated battery
3. Left for months un-used
4. Not getting enough charge from the bike.
5. Loose battery terminals.
A battery can last 3+ years without too much problem, though expect less if you live in areas with particularly colder winters. Higher quality batteries can cost twice as much, but last longer under these conditions. However... you can kill a brand new $150 battery in a day if you try hard enough :lol:
Lead acid batteries 'hate' being discharged! Can't stress this enough! As a general rule, you should always keep at least 20% charge in there at ALL times. Let it go flat, and it will never be the same
. Continually letting it go flat is just plain mis-treatment and likely to cost you in the end.
Don't leave the bike unused for an extended period of time (more than 4 weeks), particularly if you have an alarm fitted. Ideally you would plug in a battery tender. Otherwise, give the battery a charge and disconnect the negative terminal from the battery. The battery will hold out a lot longer, particularly with newer bikes that have more electrickry!
Not Enough Charge - Short Trips
Short trips can slowly lower the batteries charge. It takes a fair bit of power to start the bike, and while idling, the battery isn't getting much back - on a CBR250, at idle it may get no charge at all. If you do a lot of short trips, consider getting a battery tender to keep it charged. A battery tender is a low power charger designed to be continuously connected for long periods, which usually comes with a plug you fit to the bike and can convenient connect to. Just ask at a motorbike shop
Not Enough Charge - Bike Problem
If your battery is going flat while riding, then you definitely have a problem that needs to be fixed before it gets worse. If this happens, your bikes battery is probably providing the power for the ignition... which won't last long. Symptons will be the headlights go dim, trouble idling and/or the RPM starts limiting / missing. I you ignore this problem, your punishing the battery and causing it to go flat.
Typically there are 3 things that can cause the bike to stop providing power to the battery, the alternator, the regulator/rectifier (reg/rec) and the reg/rec plug. The alternator rarely fails, but if you suspect it as the last cause, check the service manual for how to test it. You basically measure the windings of the alternator coils with a multimeter... which isn't as hard as it sounds
The reg/rec does get quite hot, and a few problems have been due to the plug being melted and having the terminals short others, or fall out. You should also remove 10cm of the insulation and check the wires from the plug haven't melted/fused together. In some cases, the terminals are oxidised (charred) and don't conduct very well. They just need a good clean. The plug should look like this, with no meltage or black charring.
The reg/rec may likely be the fault. What is the reg/rec? It converts the alternator power to the power needed by the bike. If it fails, it will provide too much power (over-voltage) or none/little power.
You can check if the reg/rec is operating correctly with a multimeter. Measure the voltage with the bike off at the battery. A good battery will show 12.6V. If it's low on charge, it should still be above 12.2V. I'd just like to add... the battery voltage does not necessarily indicate how much charge there is!!! If you have recently charged the battery, it could be much higher, like 13.5V. Within a few hours, it will be dropping back down to 12.6V, which is function of the chemistry involved.
With a CBR250 idling, the voltage should be around 12.5V, though can still be a bit lower if the battery needs some charge and the headlights are on. Basically the battery is loading the alternator. If you turn the headlights off, the voltage will probably go up a bit higher. Newer bike are usually around the 13.0 to 13.5V at idle.
The important thing is, one you get above 3,000rpm you should clear 14 volts. Revving higher, it shouldn't go above 15 volts, and will be more like 14.3 - 14.5V. If it's going up to 16V, then you have a big problem :dodgy:
The figures I've mentioned are general, as it primarly depends on what speed your idle is, if the headlights are on, the condition of your battery and how much charge its holding - and of course the bike/model.
Although the battery may be 12.6V by itself, it actually needs more to actually 'accept' charge at a descent rate. At idle, it will still be charging a little, but no where near what it will while your riding.
Loose Battery Terminals
Yep... I've seen it a few times. Clean the white crap off the terminals with a wire scrubbing brush, and make sure the bolts a tight enough!
Charging the Battery
These batteries for the CBR250 are a 6 or 7 amp-hour capacity. Thats tiny compared to a car battery. So if you put it on a big car charger, it's going to be choked with electrons :blush: A 3 amp charger is too much. It will heat the battery more than necessary, and not do it any favours. A 1 amp charger is ideal for these, 2 amps is still fine! The batteries usually specify a full charge takes 3 to 4 hours, but for a 1 amp charger, I'd go a few more hours than that. 8 hours is good, but as always, if the battery starts getting hot, take it off charge and let it cool down before charging further.
You can buy chemicals to add to the battery to help reduce the lead sulphation buildup on the plates. Without getting too technical, it helps restore the capacity of the battery. Getting slightly more technical, the ions in the solution bind to the plates covering them, reducing the solutions charge capacity and reducing the plates ability to supply strong current. I've heard good things about these conditioners from a few people now, though never tried it myself. It doesn't cost much either, so worth a shot. When my battery is starting to get a bit old, I'II be dosing it up myself hehe... Here is one you buy...
INOX Lead Acid Battery Conditioner
Jaycar NA1420, $8.95 www.jaycar.com.au
Supercheap Auto, $8
You can also get 'battery refreshers', which as I understand, pulse the battery with very short high current bursts. These electrical shocks cause the sulphation to crack and fall off. I've never tried one or heard any reports from others, but personally... not that keen on the concept. I can see why it would work, but I can't see why it would do as good a job as the chemicals. Besides... $8 of chemicals will probably do 2 of these batteries, and these refreshers are a lot more expensive!
Jaycar MB3660, $49.95
A lot of people are having battery and reg/rec problems lately, so here is a bit more info to help with understanding the problem and what to do about it...
A battery is a device based on chemistry and it's a much bigger topic to understand than most people first realise. The voltage at the battery "does not tell you everthing". You absolutely cannot tell how good a battery is by the voltage, or how charged it is by the voltage alone. Lead acid batteries have two primary things to describe there status. If you were to use a multimeter, the nominal readings would be 12.6V (good) to 12.4 (average). If you have recently charged the battery or ridden (where it gets a charge), then it will be higher... like 13.6V, but wait over night and re-measure and it will stablise back down to 12.4 to 12.6V. This is the chemisty stabilising.
State of Health (SOH) and State of Charge (SOC) --> these are industry terms, not something I've made up. You can have a battery that is fully charged, but in poor SOH. This would be like having a fuel line that shrinks as it deteriorates. It can still supply fuel, but don't go wide open throttle for long, as then engine will get starved of fuel. If the SOH is low, the battery is probably barely coping with running the headlights, then trying to start the bike is way too much for it. Might even get the odd backfire
What to do if you're having a problem?
First thing is it would be good to confirm if your reg/rec is stuffed. With a fully charged battery, get the bike started and pick the revs up as covered in the info above, to measure the reg/rec voltage output (at battery). If it's too high... don't ride the bike. It's probably already boiled the battery - the start of your problems. Next things to go are things like headlight bulbs, brakelights and instrument bulbs. There is also the risk of the ECU dieing (which has happened) and also things like the tacho might fail from the over voltage (which has happened). It gets REALLY expensive at this stage. A brand new Honda reg/rec costs a far bit. You can buy second hand CBR250 reg/rec's, but people are getting ripped off and being sold one with the same problem of late. The economic solution is to get one off another Honda bike... usually the wreakers know what model fits what. Some might not have the same connector (fine if you want to wire it). Essentially you're looking for a 5 wire reg/reg, with the same plug and same bolt hole spacing.
Once the reg/rec issue is solved, then you can either get the battery tested or replace it. You can take a charged battery (must be charged) to a battery shop and get them to load test it. They'll tell you what the state of health is. You can test it yourself, by monitoring the voltage as you crank to see how low it gets. Hard to say what level, but after a few seconds of cranking, if the voltage isn't back above 11V it might not be in the best of shape and will be more difficult to get a hot spark.
For a new battery, the common model is the Dynavolt YTX7L-BS
which are around $70..$80. You can get expensive batteries, but these batteries are perfectly fine for condition in Australia. Look after the battery and it will last over 3 years.
If you get a new battery, make sure to fully charge it before use.... i.e. 2amp charger, 8 hours. Don't use a big charger... it will charge too fast and overheat it (doing damage in the process). It's silly to charge a new battery by going for a ride... you're not doing the battery any favours and it's going to take a while and stress your reg/rec. BTW... some people get the bike shop to fill the battery with the acid for them and charge it. But they might think 2 hours on the charger is enough and call it fully charged. Do it yourself to be sure. If you don't give it a full charge, it starts it's life by sulfating the plates and you'll be lucky to get a year out of it.
Also, if you have a charger with a the famous red/amber/green or fully charged light... ignore it. They are nothing but a crappy gimmick, and not a good indication of battery charge. Ignore it. If you have a multi-stage battery tender, then that is something you can rely on for knowing when it's charged.
Often people will charge a new battery before putting it in the bike. It's really important that you don't charge it while it's sitting on cold concrete. Sit it on some wood if needed. The concrete otherwise sucks the heat out, and the battery/solution has a hot and cold zone... bad karma for chemistry trying to properly charge the solution.
Often people putting up with with a bad battery will notice a difference in the power when they fit a new battery. Probably because the ignition at idle was crap before with weak sparks.
Above all... get off your arse and fix the problem. Otherwise, you'll be another one that is left stranded on the side of the road because they thought the problem would go away or not get any worse.