Batteries don't last in my bike - causes?

[MoggyW]

Hi All!

I have a problem with my curvy 2000 that is doing my head in. I bought it 3 years ago with no reported problems but have had this intermittently ever since....

My bike seems to quite literally EAT my battery!!

I get a new one, it's fine, then 6 months later suddenly I have starting issues now again, then all the time, and the battery won't charge or optimate enough to start the bike regularly, then not at all. At the moment the current one won't get over 12.6v when I charge or optimate on or off the bike, so it's off the road until I get a new one, AGAIN!

I'm going to crack open the Voltmeter and do some charging system testing (any ideas here?!), and I'll post up the results, but I need to do it with a new fresh battery which will be in the post.

I always get Yausa batteries, have also tried the one for the pointy, no joy. It seems to happen as much when the bike gets ridden every day or every week, it goes on optimate fairly regularly if not ridden, I have a datatool cat 4 alarm fitted, standard lights, everything else pretty standard.

Has anyone heard of anything like this? If it could be the reg/rec frying the battery, how can you test it?!

Help, because I LOVE my bike but this is making it too unreliable to keep!!

K. :(

[yorkie_chris]

Yeah check the charging system, it could be undercharging. Or the alarm could be killing it for you.

[MoggyW]

Also, I've had the alarm fitter come back and check it and say it's all ok, how else could I check it myself?

[dyzio]

Put a volt meter across it and measure what voltage you're getting at idle and 5k rpm.

Also, put it in series and measure the current with the ignition switched off to see if you have a current leak.

[AndyBrad]

TAKE THE NEGATIVE LEAD OFF THE BATTERY AND SET YOUR METER TO mA. THEN PUT ONEEND ON THE BATTER -VE AND ONE ON THE -VE LAED OF THE BATTERY. ANYTHING OVER 0.2A AND YOU HAVE SOMETHING DRAINING YOUR BATTERY.

IF OK CHECK THE REGREC (SAERCH FUNCTION) AS THIS CAN CAUSE THE BATTERY TO UNDER/OVER CHARGE. dOES THE BATTERY GET HOT? LOOK DAMAGED ETC?

[dyzio]

I take it that the <200mA is what an alarm is normally using?

Or did you mean to say "anything over 0.2mA"

[AndyBrad]

Sorry anything over 0.2a

[Matts-Yokes]

regulator/rectifier ? If its over charging it will knacker it as fast as if its under charging

[glang]

It sounds very much like your regulator/rectifier has failed. To explain a bit: the generator produces alternating current in 3 phases (3 different oscillating electrical flows) then the rectifier converts and combines them to direct current using a number of diodes. If one diode fails it allows some of the alternating current through to mix with the direct current which gradually does the battery in. Its difficult to detect without specialised instruments because the direct current voltage doesnt change much so substitution of the reg/rect. is the easiest way with a pattern part costing around 50quid. The diodes have a habit of failing if the rectifier is not well cooled or they are overloaded charging a flat battery after bump starting the bike. Hope this helps glang.

[MoggyW]

Hey,

Thanks for all your replies about this! I am hoping my latest new battery will arrive very soon so I can do some testing - but am I right in thinking if it is my reg/rec then nothing much will show up anyway?? I'm seriously thinking about getting a new one anyway from all these replies!

There is definitely not a leak in the circuit when the bike is off, I tried putting the multimeter in series already. . .

Will keep you posted!

K

[yorkie_chris]

If your reg rec is toast then you will likely see it on multimeter just from voltage test. Not seen any SVs feeding AC, but it can happen. Generally they just go kaka and under or overcharge.

[MoggyW]

Hello hopefully helpful people!

I have done some testing and the resilts are not what I expected them to be:

I charged my new battery and it read at least 13.6v before I put it in the bike, but I had to go to work today and when I got back the reading was 12.83v with the whole bike off and 12.66v with the ignition on and nothing else.

Then:
Idling engine (1,000rpm), no lights: 13.6v
Idling engine (1,000rpm), with lights: 13.25v

Engine revving (5,000rpm), no lights: 13.4v
Engine revving (5,000rpm), with lights: 12.72v

Now correct me if I'm wrong but this looks like there is little or no charging going on at all!?

I can't expect my battery to last a week like this but it has been going about 6 months each time before just not cutting it - so it must be charging a bit??

Does this look like a reg/rec fault or an I going to have to dig for my alternator, or shall I just burn the thing and be done with it!!??!

[yorkie_chris]

Next step is to check the voltage output from the alternator, remove the tail plastics and find the connector with 3 yellow wires.

You should have 70V (AC!!!) at least between each of these pairs (i.e between wire 1-2, 2-3 and 3-1) at 5k rpm.

You should also make a careful check after the reg-rec too, corroded wiring could also make the volts "go missing". You can check this by putting the volt meter on DC between the ends of the red wires, i.e between red on the reg rec and red on the battery. If there is significant voltage here, there is significant resistance.

[embee]

Then:
Idling engine (1,000rpm), no lights: 13.6v
Idling engine (1,000rpm), with lights: 13.25v



Idle speed should be more like 1300rpm, some people prefer slightly higher. 1000rpm is too low.

As well as the other things to check, make sure all the fuse blades are clean and shiny and check all the electrical connectors you can get to. Use some lube on them, dielectric grease is perfect, vaseline works fine. You'd be surprised how much volt-drop you can get from poor contacts.

Lead-acid batteries don't like being kept undercharged for prolonged periods, that might well be the cause for the short service life you've experienced.

I'd still put money on the reg-rec if I had to..............

[MoggyW]

Hello! I am very chuffed to say - I'm fairly certain my reg/rec is knackered lol!! Funny to be happy about this but it feels satisfying to have tested absolutely everything I can and decide that the problem must, most certainly, be there, and if I change it I don't have to get rid of my unreliable bike!

Hurrah! I've seen a pattern part for £70 and don't want second hand, I'm guessing this is a good price...

A huge thankyou to all who gave very useful advice - without the forum my bike would have been sold by now!

:)

[embee]

http://www.electrexworld.co.uk/home-1-0.html are pretty well respected quality parts if you want to go with a known source.