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Old 02-20-2012, 08:07 AM   #93
_cy_ OP
Beastly Adventurer
 
Joined: Sep 2011
Location: Tulsa, Oklahoma
Oddometer: 5,896
8:15am .. disappointed the predicted low of 32 never materialized. 44f degree this morning
Shorai LFX21 AH resting at 13.20v .. amp draw 98 amp @ 44f .. 10 seconds with lights and heated grips on high.... engine cranked over and fired right up... turned choke off, then cranked over to measure amp draw again.

concerned at why battery only charged to 13.21v after a 100 mile bike ride. checked voltage with lights and heated grips on... 13.8v @ about 3k rpm, 14.2v with lights and heated grips off. may need to find an adjustable voltage regulator. brushes had about 1/3 remaining and will be replaced.

window for real life test conditions in Tulsa is rapidly closing. No I don't have access to refrigerated facility large enough to hold a motorcycle.

load testing while a valid indicator of performance. it's only an indicator and cannot replace real life testing. for instance the 20AH (actual) battery is rated at 3C = 60 amp continuous, 10C pulse = 200 amps. at 15f degree battery only put out 105 amps max. while starter's draw 180+ amps with cold engine/motor oils. load testing will not reveal above information. cold starting amp loss = 50% @ 15f degree

note amp differences needed between cranking over an engine in perfect tune/warm temps (fraction of a second?) vs cranking over a balky engine due to bad fuel, extreme cold or what ever .. can extend to 10+ hard crank cycles before finally starting engine.

what's coming out is importance of learning differences between pb eq or lead acid battery and li-ion. charging is different, cold starts are startlingly different, reserve amp hour capacity is different, weight is different, when these tests draw to an end... will be writing up a list of must do's to successfully live with li-ion batteries in our motorcycles.


_cy_ screwed with this post 03-24-2012 at 06:22 PM
_cy_ is offline   Reply With Quote