09 KLX 250 parked for 4 or 5 weeks. Finally some warm weather and I decided she needed a ride. Click, click, click My battery was discharged and bike would not start. Being the impatient sob that I am, I put a 75 amp starter/charger on it and after 8 or 9 long tries it started. BUT it dies as soon as the starter button is released. It will run as long as the starter button is held down. Has anyone heard of this? I did not find anything with search. I figure I fried a relay or the switch with the 75 amp starter. Going to check out a wiring diagram if I have one and the starter switch but want to post up in case I am on the wrong track.

Thanks

 

Verify the year of the bike, please. 79?

 

Sorry for the typo, KLX is an 09.

 

LOL, I saw that too and was confused. Have you put a full charge on it and if so what's the voltage?

 

I charged it overnight and just took it off the charger. Showing 13.8 volts right now, I will wait and let it settle. Yesterday it was at 9 V, it could be fooked.

25 degrees F now so will wait a bit before I try to start.

 

Cold weather can wreck havoc on a battery. I'd see how (if) it runs without holding the starter button in. Check the battery daily for a few days, if you see a drastic drop, say .30 volts a day the battery may be bad.

 

After being off the charger a couple hours voltage is 12.85 so I think that battery may be ok. When the temp got to around 40 I tried it and it started right up and kept running. Whatever the problem was it seems to have gone away. Still curious about why it was running only with the started button pressed. I will be checking the battery for the next couple days then back on the battery tender.

Thanks for the replies!

 

I know battery tenders are very popular with motorcyclists during the off-season. But recently I had a battery ruined by leaving it on a tender. It was a marine battery I used for camping and power outages. It was less than a year old and I noticed the run time was gradually decreasing. So I took it in to have it tested and was told one of the cells was bad. Presumably from over-charging on the tender. Fortunately I got a free replacement but now I go about it in a different manner. First, I got rid of the previous maintainer. Now I charge it once a month and then take it off the charger all together. Over the course of a month it'll go from roughly 13.1 to 12.6 ish. Then I'll give it another full charge. I know it's not as convenient but I think it's better for the battery.

Here's a link to a good resource.
What You Should Know About Battery Maintenance - eMarine Systems

 

That is not a bad plan depending on the situation.
I have four bikes on tenders, two for more than 5 years. I ride enough, even in winter, that if I only had one bike I would not need a battery tender at all.

Theoretically if the tender is designed right and working right it should not overcharge a battery. I think a lot of the cheap ones that claim to be "automatic" are not designed right. Another problem is that 12 volt batteries can vary from brand to brand and even within a brand as far as full static voltage anywhere from 12.4 to 13.0 (in my experience) and even a good automatic charger that is designed for say 12.6 will cycle properly if the particular battery is not real close to 12.6.

I have read that it is good practice when keeping a battery on a charger full time to give it a break at least once a month (if not in use) and let the voltage drop off some before putting it back on the tender.

Two of my bikes have immobilizers and clocks and fancy displays that drain batteries when the bike is parked. The other two sometimes don't get ridden very often so I find it best to keep them all tended.

What messed up the KLX battery is that some fool left the tender in 6 Volt mode. I don't know how long it was like that but it possibly ruined the battery or tender or both. I went and put tape on all the tenders to prevent accidentally putting them in 6 volt mode

 

Out of curiosity which battery tender was it?

This is the one I had (which I bought brand new). I think it over charged the battery which ruined it.