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battery question

billst

Member
i am having problems with getting the bike to start. the battery i have is 2 years old and on a tester the voltage is good and cc amps are still at 200. ( battery is rated at 275).the problem is this battery doesn't have enough power to start the bike. i have to go with a new one to get the engine to roll fast enough to start. even though they are rated at 275 cca it actually tests out at 400cc amps when new. any ideas or comments on this would be appreciated. thanks
 
How are you coming up with those cold cranking amp numbers? If your getting them by a formula built into a hand held meter, I would not go by them.

Perform a TRUE load test on the battery. Using a carbon pile (or a resistive strip) tester, load the battery to 1/2 it's RATED cold cranking amps (in our case ~150 amps) for 15 seconds. Anytime during those 15 seconds the Voltage across the battery posts should not fall below 9.8 volts. (the higher the better)

CCA is actually a number that the manufacture comes up with in their testing lab. It is not something we can easily reverse engineer and pro-rate back into a used 2 year old battery.

Example: Lets say a NEW battery is rated at 12.6 volts, 20 amp hour, with a 300 cold cranking amps rating. After 2 years it is simple to compute the amp hour rating the battery now has but there is no easy way to TRULY tell you what the CCA rating is. It may now be a 12.6 volt 14 amp/hour battery, but we can not pro-rate that into a true CCA rating.

Bottom line. Carbon pile load test the battery to 1/2 of it's NEW RATED CCA for 15 seconds, measure the voltage and let the strongest battery win.
 
thanks for the reply hoople. sounds like you know your batteries. i took mine to a place called the battery pro. he sells new and reworked batteries. i don't know a lot about the process but watching him he put cables from a tester on the battery, under no load, and said the volts were good and it still had 200 cca . he said this should have no problem starting the bike. that was the only test he did. doesn't sound like he is too much of a pro. in any case the new battery is working fine. just hope i don't have to replace it every 2 years. i am going to go over your info with him next time i get over his way. thanks again
 
Check all your grounds also new battery is working now but that could also be an issue
use a battery tender when bike will not be used for a few weeks and it should last 5-6 years

+1 smitty901 and would also recommend using tender all the time when parking bike after riding.
 
Battery reserve degrades also with temperature, so the 12.6V/200A-H is not necessarily good, as HD recommends 12.6V/275A-H. You should replace that battery, if it has not been used with a Battery Tender to keep it's charge up over the years or battery was deep discharged once or twice, you will likely have a bad battery.
 
yup. all connections are good and bike is stored in heated shop. battery removed for winter and kept on smart charger up til now. another thing the guy at battery pro mentioned was that continual use of a tender will dry a sealed battery out after a while. i was planning to start the smart charger up about once a month instead of continual but now not too sure this guy really knows what's best
 
another thing the guy at battery pro mentioned was that continual use of a tender will dry a sealed battery out after a while.

In all fairness you need to first define what the Battery Pro guy meant as a "Tender" charger. We here on this Forum have more or less defined the word "Tender" as the Battery Tender made Deltron xformer in Deland Florida. Battery Tender is a SPECIFIC brand & make of charger that is microcontroller driven by firmware.

If the guy at the Pro battery shop sees a "Tender" as a general Trickle Charger,, then he has a valid point.
 
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