so straight to the nitty gritty:
87 cbr1000f. was doing just fine, running great and starting fine. had been pretty warm, first cold night in a month(30*) and then the bike didn't wanna start up. turned over too slow to start it. toss the jumper cables on and vroom. I ran it around a bit(1/2 hour or so, shut it down and restarted immediately just fine. 5min later too dead again to start. I did a battery test, 11v not running. started it up an only 11v while idling. I thought OH GREAT, alternator or voltage regulator. so I disconnected the battery and tested the voltage(12.5v at idle and 14.5 just over idle, jumped around quite a bit while reving up(13v-15v. now I'm confused haha

could it be the battery?
it runs just fine once it's started, doesn't shut down or bog.
let me know what you think guys

thank you very much -kay

 

I tried to go thru the tests from the factory service manual in the cbr1000f section.. but the service manual is for the newer hurricanes. different plugs, I can't figure out the wiring to test it. I have two plugs(a 2pin and a 6pin) the newer ones only have one plug(6pin. I tested for voltage leakage, it's right at 0.06mA of the max allowed 0.1mA. I have the battery on the charger, will load test it in the morning and update

 

Charging system looks fine. RPM'S need to be raised to get proper charging. Low voltage at idle is due to lights and other things running at idle. Charge the battery to full volts, disconnect the ground and let it sit overnight. Then test the battery for voltage, it should be the same as when you finished charging it. Then re-connect it and see if it starts. If it starts w/no problem you possibly have a short in the system. At this point you could leave it connected and see if it is dead again the next morning, that would confirm battery is good and system has a short. I, and some other people posted on another thread (dead battery) you could pull up and follow, it is a little more detailed, and has more info. Good luck.

 

Charge the battery up and have it load tested. Make sure you cables are clean and tight as well. Electrical problem tracing starts at the battery.

 

On the Hurricanes you need a good battery to start them.
If you find the battery charges up OK but while riding it starts to give problems, I would suggest you check the regulator/rectifier which is behind the side/tailpiece fairing on the left. These bikes don't charge at under 3000 RPM with a std reg/rec, which is why many of us fit after market units which have big heatsinks built-in and start charging around 1500-1750 RPM. If you find it's your reg/rec I'd suggest one from Electrex - partnumber is (I think) RR23.
Let us know how you get on

 

Sounds fine to me, when I was working on my bike I would have to jump it every time I wanted to start it because I never rode it for more than 5 minutes at a time to test out the changes I had made to it. Not enough to recharge the battery when it was flat. After doing that a few times I charged the battery up and it works fine now, starts up perfect.

As for the voltage output, sounds normal. At idle they won't put out a ton of power, just like a car. You can hear a car when the battery gets low and it's idling, it will make the car give the alternator more power so it can recharge the battery and keep the car running. Same applies for the bike, but if you give it some throttle it will give the alternator the power from the motor it needs and then it will be charging the battery. That's why when jumping another car, using an electric winch, etc...you always rev up your car because at idle the motors in both your bike and car don't go fast enough to charge the battery.

I wouldn't be worried, just throw the battery on a tender/charger and put it up to full, if you let it sit for a while and it goes dead again, you probably need a new battery. You can also just take the battery (or the bike with the battery) to a place that tests batteries and get it tested.

 

I figured it out! charged the battery all night, took it to my work(autozone) and tossed it on the autometer load test station.. was just fine. just to double check I ran it by my friend over at batteries plus and he tested it good.. it is however the wrong battery, only rated at 120cca and our hurricanes require 200+cca. I tossed the battery in anyways and sure as sh*t I'm pumping out 12.5v at idle. battery was just too dead and needed a charge ha! I'm picking up a nice 205cca sealed battery tomorrow just to be on the safe side. I'm also buying a heavy duty Vreg from a place called daves performance electronics. thank you guys for the great responses, I really appreciate it.

 

i also have a electric problem at hand.. i was riding my bike yesterday and it cut off on me. so i pushed it off the road and took the seat off since i wasnt getting the juice i needed to start back up. what i saw was a melted POS battery terminal..it had gotten so hot, that what was left of the terminal was dripping down the side of the battery. it occured to me though! sometimes when i push the start button on the handle bar it gets stuck! wonder if that could be the problem? however, the bike started back up that day when i held the pos cable to the battery. but died when the cable wasnt touching..could this be an alternator issue/ regulator issue?

 

I've seen this on cars quite a few times. I'm not sure how closely related bike and car charging systems are tho. what happens is the voltage regulator fails in a way that it lets the alternator over charge the battery. it's not just the volts that go too high, everything in the electrical current raises. I would check out your regulator. what is your year (i.e. 1987 cbr1000f) I have a new friend that works at a powersports electrical repair shop, I can ask him what he thinks. he seems to really know his stuff;-)

-kay

 

MOST likly you have a dead short. Positive to ground. If that is not the problem the start button being stuck would possibly fry the battery like that but usually the cable would burn also, and or the starter. The other issue at hand could be overcharging. What you need to do is chatge the battery FULLY out of the bike. Take it to autozone and let them load test it, and they will also be able to tell if you have a bad cell in the battery! A bad cell will fry the battery. If that checks out good before you buy a new battery (which it sounds like you need because it is melted) put it back in the bike and w/multimeter check volts before and after it is hooked up. If they are the same or close start the bike and re-check voltage. It should be around 12.9-13.5 at 3000 RPM. Any higher your problem is the charging system cooking the battery. When you start it pay close attention as to weather the starter stays enguaged. (keeps cranking)ot starter button is sticking which will also do the previous. If you do all of the above you SHOULD find your problem. good luck