Charging System

[ArizonaKid]

Okay, here's an electrical system question for you "wrenches" out there who have minors in MC electrical systems. At idle the lights on my 02 Tiger are bright and steady. When the engine is rev'ed the lights dim and actually flicker a little, to the point that it's noticeable.  In addition, the engine doesn't seem to crank over as fast as it once did and it takes a trickle charger overhight to bring the battery up to full charge (i.e., the battery isn't charging all the way under normal use). The battery is relatively new (1 year old).



Q:  Are these the signs and symptoms of a catastrophic meltdown of the charging system, or what?

[apache]

Definatly dont sound right. To start Id put a voltmeter on the battery before then after a good charge and also while running after a bit. A fully charged battery should hold around 12.8+ volts just sitting. with the bike running you should see 13.5+ volts at say 2200 RPM and perhaps a little less at idle. A new battery dosent always mean a good battery, sometimes you get duds. but either way you should check the charge system first.

[Sasquatch]

Trace every connection in the wiring.  I cleaned each connection and gained .7 volts at the battery.

[Aussie Tiger]

What you are experiencing is due to the drain imposed on the system by the efi and other systems on the bike. As you increase the revs, the efi system draws more current to feed the engine.  Usually, you would not notice this if your battery is in good condition.  However, as the battery dies, it cannot hold its charge and so cannot back up the bikes electrical system.  Even with a good battery, you will actually notice a small voltage drop (at the battery) when you rev the engine, which returns to a higher figure back at idle. Replace the battery and all should be well again.  



As a side note, most batteries are only designed for a life of between 12 to 18 months. However with care, you should be able to get at least a couple of years out of a good quality one.  In fact I've heard of some lasting up to 5 years or more!

[tcowjww]

Also, the kind of batteries usually used on motorcycles (i.e. not the specialist Odyssey types) are not designed for cyclic use.  What that means is that if your battery has ever been allowed to run completely flat (lights left on by accident, for example) permanent damage can be done to the battery - even after only one such incident.



I had this happen on a previous bike.  I'd shelled out on a quality, branded replacement battery, but after only six months I completely flattened it by turning the ignition key too far, and leaving the parking lights on for a couple of days.  The battery was never quite the same after that, and I ended up having to replace it about three months down the line.



My current battery is a Varta and is the one I purchased to replace that one I accidentally abused.  I've moved it between bikes I have owned since (conveniently the same type of battery!) and it still going strong after two years.  Never been flattened, and always optimated if being left longer than about two days.