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Old 02-13-2013, 03:12 AM   #357
Wanderer2012
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Joined: Aug 2012
Oddometer: 37
Quote:
Originally Posted by _cy_ View Post
what you are describing will put a brutal drain on proposed Shorai LFX21 ... turning motor off for several minutes with about 11 amp draw, if your bike has 2x 55watt headlights. then starting motor ...

then repeat for unknown number of times in traffic without allowing engine ample time to charge battery back up.

Shorai LFX 21 measured about 6 amp hour under a 1C discharge ... this means that battery will sustain 6 amp drain for one hour. or 30 minutes under 12amp discharge.

your headlights don't understand PB/EQ .. they drain real amps.

my recommendations are Odyssey 925 with 26AH, unfortunately 24lb... otherwise Shorai LFX36 with about 12AH (actual) might do it .. if you charged to full before you started and your total down time not exceed 60 minutes @ 12amp drain.

you'd be better off turning off bike with key, killing everything including lights during stops

watch this video, which stress LFX18 battery very similar to what you described
CY...
Ok cool, thanks heaps for sharing your thoughts and wisdom...
I never related to the headlight using so much power, currently has a H1 Bulb, 55w halogen, one only, but by the time we add in tail light, stop light, ignition, indicators, and a hit on the starter motor, i can see the battery getting a hard time...
That said this scenario isn't a often event, but just an extreme that got me thinking, given its summer time, and while stop start riding the other day i decided to shut her down each time i had to sit at a red, try keep the engine temp down being air cooled and all...

I see the big 36 Shorai is up in the mid $300 range, so that will be more toward $500 of my money, time it gets here, so thats out...
How long would you expect a BMW Gel 19ah to last, Im very suprised having just bought my bike, to find its original battery still in there and going ok...

Also just started using a charger, CTEK XS3600, But have been using on motorbike mode, and now just read online i need to use the car mode, Is it a good idea to use often and leave on for extended periods, my bike seems to be out maybe once a week currently, but less when winter comes...

Just a thought, How good a job does the BMW bike system do at charging the Shorai type battery, as it wasn't designed to do so... Think the listed output on my bike is 600w...

Thanks for the very informative thread to...

Cheers Jeremy

Wanderer2012 screwed with this post 02-13-2013 at 03:23 AM Reason: Add some on...
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