Hi, I'm after a bit of help here. A couple of weeks ago my KLE decided it wasn't going to restart when I stopped after an ten mile or so ride. I'd been riding it around for a few months before this without any issue. On this occasion it was definitely a flat battery and I ended up having to charge it for the bike's next outing. On the next trip out a similar thing happened after a trip of about twenty five miles (although it restarted twice on the trip when I stopped off for a couple of things). I've checked the battery after recharging it again (it is only six months old), and it is holding charge - currently 12.6v.
I suspect it is the rectifier at fault, but in all honesty don't know a lot about motorbike electrics! I've got a copy of the service manual, but the tests in it don't make a lot of sense to me! I know that when I run the bike, the voltage across the battery terminals slowly drops, so I know there is something afoot with the charging circuit. It also worth adding that when I bought the bike the rotor was damaged, and the stator and rotor were replaced with secondhand ones. both of which looked to be in good condition, so I don't think the fault lies there.
Could anyone offer me some advise, or simple checks I can carry out to diagnose what the fault may be? - I'll be really grateful!

Hi! A am also no expert with anything electric, but my reg/rec killed it self last year and was overcharging the battery. If you dont have a servise manual here is a screen shot of the part where undercharging problems are noted:


If I were you I would first check the most simple thing, that is checking all connections and plugs and than go to the more complex stuff.

Cheers!

__________________
->Honda XL125V Varadero '08 sold
->Kawasaki KLE 500 '05 riding it, like I stole it

Thanks Ghosty, I had a quick look at the connections and can't see anything wrong with then so Ithink I'll invest in a new a rectifier, and hope it sorts it out!

some advise that may be help..I have same experience as you before..i have fix a voltmeter at my KLE..while running the charging voltage should 14V above..if shows 13.5.V or something below 14V, its not actually the RECTIFIER problem...Its the BATTERY itself, of course when observe/test with Multimter..the battery shows 12.5V, but try to push the bike START BUTTON the voltage will drop drasticly to 7-8 Volt...the battery CANT hold the voltage to provide enough Current to the starter...I have change the battery..and the problem solve.
The first syndrom is same as you..1st the battery flat...recharge back, and okey for a while, than flat again...until its fail to start at all.

after your battery has been on the charger it measures 12.6? thats fully charged? If so that is quite low. A fully charged 12v batt should sit at least 13 if not 14v's. Is it a sealed battery? if not check your fluid levels. From there you either have a ground leak or rectifier/alternator/wiring problem. The Manual does describe how to check these things but it can be confusing if you do not deal with electronics alot. Hope you can work it out.

Rash,
Sorry, but you are off base with what you say.


For most 12v batteries, they will not hold more than about 12.5v-13v maximum.
They will show a voltage higher than that when first disconnected from a charger or after running the bike for a while, once they have been at rest for a while they will commonly come back below 13v

12v batteries need at least 13.8v [possibly more in some cases] to recharge the battery from the charging system.

It is NORMAL for a battery to drop way below 12v when starting, this does not mean the battery is faulty, it will quickly recover to normal voltage after you stop pressing the starter button or when the bike/car starts.

If new or recharged batteries are going flat after a relatively short time then the charging system on the bike is not putting enough voltage in to the battery.

A multimeter test at the battery terminals while the bike is running should give a voltage reading of at least 13.8v [or whatever the owners manual says the charge rate should be].

If the voltage reading is at or above the recommended figure then the battery needs to be load tested, this can be done by you but is far safer to have it done by an auto electrician with a proper battery load tester.

Leon, you are on the right track with also testing for voltage leaks.

If the charge rate is correct and the battery passes a load test then voltage leak is the next thing to look for.

Also note, if your charging system is putting in a charge rate much higher than the manufacturer recommends then you will cook your battery and it will fail in a very short time.

[I worked in car workshops for some years as an automotive serviceman]


LaCarretera

I would be checking the charge rate going in to the battery when the bike is running, I would bet a six pack of that it is under charging.

After that then get the battery load tested.

Hope you get it sorted out.

You are correct ocker, sorry i should have been a bit more descriptive. I meant that the batt would be up around 13-14v straight off the charger.

Do what Ock suggests! He's a good fella!

G'day Leon,

Wasn't picking on your post, just adding my experience and 2c worth.

The more feedback the better it helps when trying to sort bike problems in my book.

Went and bought myself a tank bag for the KLE today [the Strom one is too big for it], and a new Nolan flip helmet.


LaCarretera, let us know how you get on with sorting the problem.

I may also be looking for a new battery for the V-Strom and would be interested to hear what others have found that work well.

Thanks all for the advise.
I haven't had a lot of time to look to the bike until this morning. Yes Ockerstrom, you are correct, it is undercharging. It is as if there is no charge going through to the battery at all!
I bought a replacement new rectifier off ebay in the week, but it only has five wires in the multiplug connetion, not six . I'm not exactly sure what the sixth wire is for.. it looks like it might be dumping excess voltage to earth (?) A friend suggsted this as the rectifier bolts to a metal bracket on the plastic undertray instead of the frame, so perhaps it can't dump as much excess as heat. Anyway, I'm going to send it back.
I took the cover off the generator earlier and inspected the stator, which looks physically fine. I know the manual says that I there shoud be resistance of about 0.37 - 0.46 between the windings, but I can measure 1.1 (any yellow, to any other yellow). Would anyone else mind checking the resistance they get on their bikes? (Either at the multiplug where the cable leaves the engine casing, or at the rectifier), I'd be really grateful, as I'd have a better idea as to what is at fault.
Many thanks for all your help so far.

1.1 ohm? I will measure mine this week and let you know.

But check what the unit value is. What voltage are you getting across the batt with the bike running?

Yep, 1.1 ohm.
With the bike running I think I was getting 12.6v across the terminals. It definitely wasn't going up, even when I increased the revs up to about 4000.

Have you done an insulation resistance test on the windings of your stator coil? Perhaps the windings are shorting under voltage. I stand to be corrected but the stator delivers about 60 volts AC between the phases (it's a three phase stator/alternator) at 4000 rpm. Is the rotor not slipping perhaps?

I've fixed it !
I successfully checked the ac voltage coming from the stator as 60v (ish) at 4000 revs. Then, as I pulled the multimeter probes out of the connector the red/white wire in the rectifier mulitplug caught my eye. I gave it a prod and it looked a little loose, so I prodded it some more and the wire came out! The spade in the multiplug had snapped off / corroded through, leaving the bottom of the spade in the multiplug and the wire disconnected, but hidden from sight within it. Within five minutes I had another spade crimped on the wire. I reconnected it and performed a little dance of joy as the multimeter showed 14.2v across the battery terminals with the bike on tick over!
Thanks for everyone with their help on this. Auto Electrics is clearly not one of my strengths, but everytime something breaks I learn something more!

Well done, persevering pays when trying to solve some problems.

At least you didn't go and buy yet another new battery.

Well done! Auto electrics can be a real pain in the ass sometimes.