CBF1000 => Lighting, Electrical, and Wiring => Topic started by: KiwiBob on 21 January, 2020, 01:11:09 AM

Title: Charging Issues
Post by: KiwiBob on 21 January, 2020, 01:11:09 AM
Hello, I've been on here a few times reading the wealth of info. Including a lot of the information about stator and charging issues. My CBF is a 2009 MKI with 34 000 km on the clock.The problem is the battery doesn't hold charge on a ride. I've charged the battery overnight, installed and gone for a ride. Stop for a break, bike won't turn over. Bump start her and ride home, bike still won't turn over.
So having read the threads about the stator this is what I've found; stator wires all show around 0.4 - 0.6 ohms resistance, all stator wires show OL when grounded to frame, when charged battery starts bike easily, shows 13.5 volts charge across terminals on idle which rising to 14.1 volts as I rev the engine and doesn't go higher as revs rise.

Can anyone point out something I've missed or that looks wrong?

Regards, KiwiBob
Title: Re: Charging Issues
Post by: Shed on 21 January, 2020, 01:31:47 AM
Before you go down the stator road, have you tested the battery itself? Is it good?
A surface charge on the battery (when you first fit it to the bike from the previous nights charge), and the ability of the battery to hold a charge are two different things. The 14.1V charging rate you state is fine.

Load test the battery first :028:

This vid should help:

Title: Re: Charging Issues
Post by: KiwiBob on 21 January, 2020, 01:44:10 AM
Hi Shed, I watch the very same video! I did the test as per video and voltage drop on cranking is down to 9.9 volts. Which according to the video is borderline. What do you think?
The battery is less than 18 months old. I did take it back to the shop I bought it at and they charged it overnight and tested it and declared it ok.

Regards, Kiwibob
Title: Re: Charging Issues
Post by: Shed on 21 January, 2020, 09:58:14 AM
If the battery is just scraping by now, it's only going to get worse. Is the 9.9V from fully charged overnight?
18 months does seem a little short on the lifespan, but if it's dying, it's dying :127:

You've mentioned going for a ride and then the bike not starting. Does it not crank at all, or very very slowly/barely? So, repeat that ride scenario, go for a ride, but come back home before switching off, (rather than being stranded or bumping!) then take your meter out and see what reading you get. If this is a relatively short ride from fully charged and the battery is now flat, then it's the battery, or you have a large current draw (rather than a parasitic draw) flattening the battery in a very short time, but in the first instance I'd be suspecting the battery.

Many factors contribute to how long your bike battery lasts, charging, storage, use, demand from accessories, etc, etc, with most batteries seeming to be between 2-4 years lifespan, but there are always exceptions!

The shop is just doing what you're doing charging overnight, but what 'testing' are they actually doing? Simply charging a battery & properly load testing a battery are two very different things.
Unless your battery came with a warranty, personally, I'd just bite the bullet and buy a new one. Far cheaper than a, possibly unnecessary, stator job. I seem to recall someone on the forum who changed stator & reg rec, only to find no change, then they ended up fitting a new battery and issue was solved. For me, that's the expensive way around, so I'd go new battery first.

Stock battery is Yuasa YTZ10s, size 150L x 87W x 93H, Type AGM 12V 8.6Ah 190A, but plenty of good  YTZ10S alternatives out there.  :028:

For eg:


Title: Re: Charging Issues
Post by: KiwiBob on 21 January, 2020, 11:11:20 AM
Thanks Shed, the 9.9v was straight after charging. Iím going to check it again in the morning and see what itís like. On the weekend it cranked once then nothing but clicks. Your ride idea is a good one. I was thinking of how to achieve the same test without getting stuck somewhere. 🙄 Iíll perform a load test if it will still start the bike then.
After testing everything today Im coming to the conclusion the battery must be at fault.
Thanks for all your help and ideas as well as the links.

Title: Re: Charging Issues
Post by: KiwiBob on 23 February, 2020, 04:28:54 AM
Thanks for the pointers people, turned out the charging system is all good and the battery was cactus. Bike has a new battery so went for a 150km ride today in spite of the 33 degree heat and the bike started first time every time.

Title: Re: Charging Issues
Post by: Art on 23 February, 2020, 09:50:55 AM
Happy Days