Hello,

New here, new rider and new owner of a used 1990 EX500. Here's my story, last week I bought a bike for $600. It have 27,000 miles on it. New battery 3/12/08. Drove it home, 15-20 miles away. As soon as I got home I turned it off and tried starting it minutes later, but no luck. At first couple of tries the engine would crank but a weak one. Then no crank but just clicks. Then nothing at all. Figured that the battery was dead so I charge it at work for couple of hours, from 8am to 4pm. Took it home and I was back on the road. Added another 6miles and stop for a rest. Guess what, same problem the day before ??? Two days later took battery to dealer and they found that its faulty "can't hold pull charge" well OK, better than having a problem with the bike itself. Same day I bought a different battery from a different dealer, while the first dealer charges my replacement battery. Plug the new battery purchased 4/1/08 and boom bike never sounded so sweet ;D

Run for two miles before I call it the day. Today 4/2/08 I rode it again and logged another 11miles. Just 11miles of leisure and fun. Got home turned it off to rest and when I decided to hit the road again... Guess what? :'( Same problem... again. >

I've ordered the Haynes repair manual couple of days back. Was wondering if any of you guys ever encountered what I'm facing. I love this bike, for 90's kawi it looks great. Hoping that anyone can shed some light. I'm thinking that there's prolly something that's draining my battery or charging system not working? Oh by the way the first owner installed a box that makes the brake lights to flash when you press brake. Not sure how to unplug since I don't which wire goes to what. Please help...

 

I'd take it back to the dealer. Either the battery wasn't properly set-up and charged, OR you have a short in your electrical system that is draining that battery.
Finding that fault in here will be nearly impossible, but a dealership tech should be able to find it lickity-split, (or take the blame if they didn't set up the battery properly.)
$600 is a stellar buy for this bike, so hopefully you've still got a little of that money you saved.
Good luck and let us know how it goes.
Peace!
-CCinC

 

Just got of work and did a suggestion by a friend.

Do you have a multi meter? or any device to measure DC voltage?
Measure the voltage in the battery with the bike off.
Start the bike and measure the voltage. The voltage should increase.
If you get NO increase in voltage set the multi meter to the AC range and measure the AC voltage across the battery at 3500rpm.

Here's what happened. Bike off I checked the voltage w/ a multimeter. It reads 14v more or less (its an interstate "high performance" battery). When I turn the key to on, with the meter still attached the voltage drops to 12v or lower. Noticed that the voltage was going up so I waited till it hit 12.5v before I tried starting. Tried starting the bike, it cranked but little then just clicks. Looked at the meter and it reads 8v. After that first try I turn key to off. Battery reads 14v, turn it to on battery drains back to lower 12v. But noticed that the voltage just continues to drop. Turned key to off again meter went back to 14v more or less. Key to on again voltage drops and just keeps dropping this time.

 

Sounds like you've got a short in your system leeching the juice out of it.
If you feel comfortable using the multimeter you can test each of the connections, but there are dozens of them. I'd get a copy of the factory service manual which will itemize all wires in the electrical system AND list the possible troubleshooting routes.
I've never had much luck; electricity is black magic.
Good luck and let us know how it goes.
Peace!
-CCiNC

 

ok, purple part: It seems normal enough.. [*]14v with no load. [*]Turn key to ON (no crank), a few sensors, lights, etc.. takes a few voltage off (down to ~12V).[*]Crank: voltage drops to ~8V (not sure if it should go down this low) but I'd believe it to be ok.

maybe tell us what the batteries' Cold Cranking Amps (CCA) rating. (though these are tiny engines.. hmm )

blue part: not so normal[*]14v with no load. (a-ok)[*]Key to on (no crank): ~12V and keeps dropping

From your description, It seems that something got *activated* during cranking and failed to disconnect upon key-to-off. Could be a sensor.. I dont know.. there is a way to determine which system it falls under.

Do the purple part again + the blue part. Oh, before the blue part, make sure the fuse box is open. Do the blue part then start pulling one fuse at a time. Once the voltage goes back up to around ~12V+ you know you found the culprit. Notate which fuse you just pulled and you have now isolated the electrical problem.

Good Luck!

 

Thanks for the post guys. I haven't had the chance to troubleshoot since it has been raining a lot lately "no garage". I know have the Hayne's Repair Manual and will try to tinker w/ the bike tomorrow, weather permits.

Regarding galen31075's post one thing I forgot to mention was that the battery was already low on voltage when I did the readings. I charge the same battery "Interstate performance" and checked its voltage, it reads between 18-20 not sure why but that's what I'm getting no load. Same day after 13-16 miles of riding the bike died on me and I had to push my bike back home [sm=smiley26.gif]. Check the voltage w/ no load still plug in the bike and its down to 14-15. At those number bike will just click away and if cranked some more... well you guys already know what will happen.

So to recap bike start w/ a battery that reads 17-19+. At 16 below just crank once then clicks. Anything lower and I get more clicks no crank. Then finally, nothing.[sm=smiley11.gif] My multimeter is on Vdc 600 "since the guy at Sear's said just put it on highest". I hope what I'm typing makes some sense or atleast logical, not my bike problem but how I'm explaining things.

I haven't had any battery dying issue for two days now since I'm swapping my battery daily and I ride less than 10miles give or take. I'm pretty sure though If ride longer I will have the same problems. I do check the voltage every after riding and voltage go down.

I will try galen's suggestion and post my results. Thanks again

 

Regarding Galen31075's suggestion I didn't do it because my voltage have not drop drastically like before.

Did the following test though from Hayne's Repair Manual.

Charging System Test:
Multimeter set to Vdc 600/ light on
idle 18
2k 8
3k 16-17
4k 14-15

Multimeter set to Vdc 600/ light off
idle 12
2k 15
3k 15
4k 15

Alternator Unregulated Output Test:
Multimeter set to Vac 600
4k rpm 1st pair 96-97
2nd pair 94-97
3rd pari 96-97

No Alternator Stator Coils cont. test was done "should I?"

Regulator/rectifier checks:
For this part kinda confuse and not sure If I did it correctly or not.
Tried following the instruction from the manual and all i'm getting is 1 on all combination in all the ohms range.

Used a fully charged battery when I did these test. Never got to run the bike much after test since I kinda finished late and totally forgot to check how much voltage the battery has after the tests.

Please advice/correct if I did something wrong or didn't do something. Thanks guys.