12.6v to 12.8 is fully charged.
ah try again, it depends on the health/ age of the battery, a NEW battery, no, a OLD failing battery, yes
13.1 is fully charged resting state of a NEW 12v AGM or Flooded car/motorcycle battery. 12.8 on that same battery is about 90%
a used old battery like OP here, 12.6 is SHOT and is NOT going to give you enough power to even try the starter, on a GOOD battery that's about 65-70%
every time you run a battery down past 50% you do damage.
You might want to head over to candlepower forums and get reading.
BUT in general for a average crappy battery from Walmart this is the chart for you This chart can ve off by +/- 25% based on the age and other factors you can only find by load testing the battery. Lets say you have a 3 year old group 37 battery rated at 750CCA its been in a car out in the hot sun and COLD Colorado winters EVERY DAY for those 3 years and gets tested at a shop to be a 75% of its capacity using a crank load tester so now that battery is only good for ~560CCA but it still works and starts the car, its MAX voltage you WILL EVER SEE from that battery on a tender at rest is about 12.65 to 12.70... this is now its max 100% charged state thus shifting its charge % down the graph curve based on temperature. This is just as an example, the multiple ways battery get damage can effect it from sulfates to crystal damage, low acid % ect...
no battery ON EARTH was or ever will be fully charged at 12.6 volts that was rated for a 12v system.
I am not trying to piss on you about it but if you have experience with things then please do chime in but your little comment there was not accurate and could drastically throw off Thadorod or ArekDeBoss from trying to diagnose those issues. ALSO the ECU on the 1st and 2nd gen rockets SHUTS DOWN at 12.6 or so when talking with Tune ECU and MUST be on a charger as the ECU wants to see 13.4+ volts as it thinks its running so if you have a busted battery with no capacity maxed out at 12.6 volts like discussed here, the bike may NEVER even start due to the ECU not getting enough volts. 12.6v is NEVER considered fully charged. Please become informed!
12-v-Battery-State-Of-Charge-website(1).jpg
 
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I guess I need a new battery.
What would you suggest?
whatever you can afford locally. stay away from any and all online seller/shippers you cant locally visit. Batteries plus is great. GO AGM if you can $$ for it
there are only 3 manufactures that make batteries for cars/trucks/motorcycles, they all go though QC and get sold accordingly to there crappiness across thousands of "brand names" do not be fulled thinking one battery is better than the others. well.... for the level you care about at least as long as you shop local to you, put your receipt in the pocket for your reg and manual under your seat so when it becomes a problem you have the warranty there ready.
 
I was having a battery draining issue with my car and found there was a high resistance between the primary and secondary winding of the starter coil where it should be open circuit. The primary coil was connected directly to the battery +ve terminal, so the voltage was leaking between the windings to earth.
Because of the resistance (vs open circuit) it was pulling the battery voltage down too, so this maybe a good sign if the battery voltage is very low. It looks like there are 3 coils fitted to our rockets, so you could try disconnecting each coil while monitoring the battery voltage, and if the battery voltage jumps up when one is disconnected, this maybe the offending coil.
Just to be clear this is an issue I had with my car, not my GT; just offering another idea.
 
Put the multimeter to each fuse one at a time on milliamps, the black probe to the battery negative and the red to the metal part of the fuse prong. Some fuses have access from the backside of the fuse but it's easy as you only have a few to check. Key off there should be 0. The one that has something drawing power is the circuit you investigate. Go unplug everything that is on that fuse, then start one by one plugging things back in.
It's not hard. Just can be a little tricky at first.
 
Mine since new sits at 12.6 volts fully charged and stays there for a good long time. Because of this thread, today I decided to check the parasitic loss and, after a very brief surge of the computer coming online (<2 seconds), it settled at about 5 milliamps. I turned on my fob next to the bike to see if it would have an effect, but there was none. The system doesn't seem to care until you thumb the switch (but I wasn't going to do that with my meter still hooked up inline, as it would blow the meter's fuse).
 
Mine since new sits at 12.6 volts fully charged and stays there for a good long time. Because of this thread, today I decided to check the parasitic loss and, after a very brief surge of the computer coming online (<2 seconds), it settled at about 5 milliamps. I turned on my fob next to the bike to see if it would have an effect, but there was none. The system doesn't seem to care until you thumb the switch (but I wasn't going to do that with my meter still hooked up inline, as it would blow the meter's fuse).
5ma is NOTHING, im used to seeing a issue with things in the hundreds, usually about 200 to 400. 5ma would take 1,000 hours to do ANYTHING you would notice. lol
your battery new, was not new and was damaged or defective from the factory. this is why it is IMPORTANT to buy locally, all batteries shipped in the USA MUST be at about 50 to 60 % charged for safety reasons and usually that always means 12.6 volts. it hurts a battery to be used new like that and should always be put on a charger before being used. this is a critical moment for a new battery. i learned that the hard way. a healthy battery is 12.9 plus
 
your battery new, was not new and was damaged or defective from the factory. this is why it is IMPORTANT to buy locally, all batteries shipped in the USA MUST be at about 50 to 60 % charged for safety reasons and usually that always means 12.6 volts. it hurts a battery to be used new like that and should always be put on a charger before being used. this is a critical moment for a new battery. i learned that the hard way. a healthy battery is 12.9 plus
You claimed that "12.6 is SHOT and is NOT going to give you enough power to even try the starter", which is clearly not the case, so you don't really have any credibility.
 
You claimed that "12.6 is SHOT and is NOT going to give you enough power to even try the starter", which is clearly not the case, so you don't really have any credibility.
it is on a battery that is dead , clearly yours is not yet.. but getting close and i specified that in another post. The skill to understand something within context of the entire statement seems to not be a skill you possess. I know I may not be the best at communicating my point but I did lay it all out and it's not my fault you chose not to read my rambling. I did actually say "may never start" not "will never start" your battery is on its last legs. You will find one day it won't start but it reads 12.5-12.6v. I forget exactly what the ecu cuts out at but you might want to check out the threads about tune ecu and why you must be on a battery charger when you do a tune.
 
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