Dear all,
I've had my 1200 Sportster for 19 years and it's always been a bit "heavy" on batteries, no battery (Harley, Bosch, Varta etc) has ever lasted longer than 3 years (but generally only 2). I've always put this down to having an alarm fitted but about 3 years ago the alarm packed up, as it was a Datatool type I've isolated it with the security key supplied so it should no longer be a drain on the battery, since then I've got through 2 batteries, the last one (a Tashima, I know, cheap ) only lasted 10 months. Should add that all the batteries I've had have been on a trickle charge through a "Optimate" when the bike isn't being used.

I've now fitted a pukka Harley battery (at great expense), when I checked the alternator charge to the battery at 1000rpm I'm getting 14v (fluctuating), anything over 1000rpm gives a steady 14v+, does this sound a bit high? I'm thinking that this is why I've been getting through so many batteries over the years.

Would appreciate any guidance on this, thanks in advance.

Regards.

 

14+ is not specific enough. Id say over 14.5 is too much.

 

My first thought is the voltage regulator should control the charge. Don't know if this article is helpful but it can't hurt.

http://racetechelectric.com/ft-751-v...egulators.html

 

Thanks for the replies and link, I should get a chance tomorrow to put my voltmeter on the battery and see if the voltage exceeds 14.6v at a higher rpm, I've used a LED indicator unit today and that just shows it's over 14v.

Regards.

 

The acceptable charging range is 13.5 - 14.8 VDC.
Fell lucky, I never get more than 14-16 months from any battery, including Harley's AGM.

 

I don't know what you mean by a voltmeter, but use a decent multimeter. Also read the Stickies in the DIY Electrical section on checking your charging circuit. They will help you diagnose if you have a problem and what the cause is. As for your battery life mine over the years have lasted from 6 months to about 12 years. For best life buy AGM-type batteries, not wet cell - they ain't cheap but are built to high standards.

 

Wow, my battery is original, 2009 model. It's never sat without being ridden for more than a week, but it's also never been on a tender.

 

Put my DVM on the battery today, 13.8v at 3000 rpm, so don't think it's the voltage regulator that's causing any problems. Hopefully with the HD battery now fitted and the alarm isolated, this battery should last a bit longer.

Regards.

 

You don't have to think, old chap - read post #6 again and follow the tips in those stickies! "the regulator should be putting out 14.3 - 14.7 vdc at 3600 rpm" etc. If the alarm is working OK there is no need to disarm it, I've had a Datatool on my Glide for many years without problems.

 

do you let the bike sit for extended time on the "battery tender"?
have you checked it ? or assume it is working?
some will not fully charge a low battery.
Just my experience