Life depends upon the load given to the battery. Yes, please do get back and let us know if issue us resolved

Battery life is 3 years for a Motorcycle.

Do a load test, Google for my article on Diagnosing Motorcycle Electrical systems, it's on Teambhp, I've mentioned the steps in detail eith pictures of the same being done on my P220.

Simply checking volts won't give you a correct read as surface charge can be misleading, hence why you need to do a load test.

Better to change your battery. 4+ yrs is indeed a very good life and i wouldn't advice you stretching it further especially when it exhibits such intermittent behavior. These bikes depend on electronics to a greater extent than your activa/splendor and so you do not want to be straining the battery/charging system or electronics with a old dying battery.
A load test will give you a better idea on the health of the battery (especially on batteries a few yrs old) than just the voltages.
A small example of my recent experience with the battery on my D200. It is 4 yrs old and the stock battery that came with the bike. Over the past yr the bike wasn't as regularly used everyday (used to sit for a couple of weeks unused) A few months ago it popped up the low battery warning and using it for a few km, the error vanished.. but a load test (done at the ktm svc with their battery tester) did indicate that a replacement was required. I haven't replaced the battery yet and had the low battery warning twice since (with the jg error and console/clock rebooting/resetting during a start), which goes off after a few km of riding.. I have been doing some 130km runs on the weekend and this has prevented the warning appearing even if the bike sat unused for 2 weeks (due to the battery attaining 'sufficient' charge on such a long ride)... but when i thumb the starter, i do feel that there is a slight strain from the starter/cranking before it fires up and not a crisp fire up like it usually was.
I know I am pushing it and would be replacing the battery in the next couple of weeks. So I have been carrying a jump starter around in my backpack in case it dies on me.. and trust me it happens.

Just another point - are any of your wires cut and touching each other?
I have had a rat bite off wires and corresponding blown fuses.

P.S: My yuasa has not been changed for the last 6 years. Will be changing it in the next service though.

Regards,
Mithun

Thank you very much for your valuable advice.
I really appreciate it.

Any updates brother?

Yes sir,

As advised I checked the battery terminals, there was some rusting on the battery terminals and connectors. This is the first time I have opened up the battery compartment in all these years, so I'm not sure if the rust buildup was gradual over the years or the recent heavy rains caused it. I scraped the battery terminals with screw driver, removed all the rust deposits and wiped them with a dry cloth, did the same thing with connectors and reconnected them. I also applied Vaseline on them to prevent further rusting.

Now it has been a couple of weeks and there are no further problems so far, so I am starting to relax a bit. But as you said that 4.5 years is already a good life for a battery, I'm keeping an eye out for other signs like, headlight brightness and weak horn or delay in cranking the starter. I'll replace it on the first sign of trouble.

Thank you again for all the help and advise.

Guys,

One quick question. What speed does a Stock Ninja 250 do at 8000 rpm on the top gear?

Mine does 100 kmph at 8k rpm on the 6th gear.

Thanks in Advance.

Mine is 80 at 8000, 100 @ 10000.
Redlines at 15000.

That is a huge difference. How come 80 at 8k rpm? Have you done any modifications? I am yet to get the Vacuum Sync done. Odo at 30600 kms

Nopes..stock bike.
I did a vacuum sync when service was with Bajaj - about 4 years ago.
Mine is 30615 now - 7 years down the line. Recently plonked an Exide VRLA. Stock one lasted 7 years.

I dont understand why such difference in the speeds at the same rpms.