2003 ninja 250 acting weird after battary recharged

[rymonroe]

I have an 03 ninja with 5000 miles on it. All maintenece is up to date. I couple of weeks ago I left the key in and drained the battary. I treid to jump start it and let the alternator charge it up but it dident work. Eventually the bike acted like it was out of gas (which I realize was because the battery was not charged). I borrowed a friends charger and charged the battery overnight. It seemed to work fine after that, starting up each time on its own. The only problem was the fact that once the engine warmed up, the bike would not idle. It would idle just fine cold but once it got warm it would die without at least a little constant throttle. I took it on the highway today and it started running really rough. It would barely do 60. The engine seemed to be catching on and off like the mixture of gas/air was off. I even heard a few pops from the exaust. I went to walmart to buy a multimeter to test the alternator and battery. When i went back to the bike it ran fine all the way home. It was weird. I was wondering if anyone has any ideas on what could be the problem. I also have no idea how to use the multimeter to test the battery or alternator so help the would be GREATLY appreciated since I think the problems there. Thank you very much for your time.

[sxgt]

as far as I know the battery only has to functions, light the lights when the bike is on but engine off. 2nd is to Start the bike. Once the bike is already on the alternator should take over all electrical responsibility and be charging the battery slowly.


"All maintenance is up to date"
air filter too? spark plugs?

your alternator may be giving out. Do your lights dim any?

[love2ride]

Actually the battery function is for starting, lights, spark plugs, and any other accessories attached.

The charging circuit consists of three parts: the AC generator, the battery, and the Reg/Rec. If you unplug on of the battery leads the bike will die, it is not like on cars. To check the battery put the volt meter on DCv. While the bike is running put the leads on the battery, run the engine upto 3kRPMs, you should see between 13.5-14.5 volts DC. If it is lower, than you have a charging problem.

The bike dieing while riding could be the battery has had it since it was drained. Battery not charging. The bike sat too long and the carbs need to be cleaned. Something blocking the air inlet. Valves need to be checked/adjusted.

[RichLockyer]

Original battery?

[rymonroe]

It is the original battery I tested the battery and alternator. They were both good. Has anyone ever heard of a bike idling only when it's cold.

[RichLockyer]

A battery from 2003 that has been put away every winter isn't good... especially if it's been run dead by leaving the key on.

75% of batteries fail in their first 36 months... you should have replaced that battery in 2006.

In addition, every time a battery is deep cycled, it loses as much as 20% of it's capacity, so even a brand new battery can be "killed" in a matter of weeks if a charging system problem results in the need to put it on a charger repeatedly.

What voltage does the battery drop to while you are cranking the engine? If it's dropping to below 10v, the battery is shot. It should be 12.6 with no load. Below 12.6 is suspect, and below 12 is dead.

As far as idling but not running at high speed, that is a classic sign of a weak battery or charging system. At low RPM, the coils have time to properly saturate and fire. As RPM increases, saturation time is reduced to the point that the coils can no longer produce the energy to jump the plug gap and it misfires.

Not idling hot... it could be the coils... but they normally would fail at speed. I'll bet ya' $10 that if you replace the battery it'll be fine.

[rymonroe]

Originally Posted by RichLockyer

A battery from 2003 that has been put away every winter isn't good... especially if it's been run dead by leaving the key on.

75% of batteries fail in their first 36 months... you should have replaced that battery in 2006.

In addition, every time a battery is deep cycled, it loses as much as 20% of it's capacity, so even a brand new battery can be "killed" in a matter of weeks if a charging system problem results in the need to put it on a charger repeatedly.

What voltage does the battery drop to while you are cranking the engine? If it's dropping to below 10v, the battery is shot. It should be 12.6 with no load. Below 12.6 is suspect, and below 12 is dead.

As far as idling but not running at high speed, that is a classic sign of a weak battery or charging system. At low RPM, the coils have time to properly saturate and fire. As RPM increases, saturation time is reduced to the point that the coils can no longer produce the energy to jump the plug gap and it misfires.

Not idling hot... it could be the coils... but they normally would fail at speed. I'll bet ya' $10 that if you replace the battery it'll be fine.

When I crank the engine the battery drops to only 10.5. At idle it is about 12.75. When I rev the engine, it gos above 14.6 The previous owner may have replaced the battery, I just assumed he did not. The battery seems to be strong no matter how I test it Ever since I got back from Wal Mart with my Multimeter, the bike has been symptom free. If this starts to happen againg, I will test the battery to see what it readsl.Thank you for the help rich.

[Streaking Tiger]

I would agree with the post indicating the carb needs cleaning. Maybe a butterfly choke or something that's sticking when it should open/close and can't do that.

It's not the battery once it starts - or at least that's my guess.

[rymonroe]

Well, it ran well for a while and then started doing the same thing (wouldent idel). I measured the volts while it died and they never went below 12.6V. I cleaned the air filter but that did not fix the problem. I'm going to drain the float bowls before I try to clean the carb. Can the carb. develop a problem after only 14 days? Does anyone know of a good DIY manual online for cleaning the carbs.

[love2ride]

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