stalls sometimes when applying throttle

[ninja12345]

Hello everyone. I had my 2008 ninja 250r for 1.5 years now. I bought it at about 4000 miles and it has about 4900 miles now. I did about 70% of the riding this year. The last time I rode was about 2 months ago. I have not done any type of maintenance on the bike since I bought it. I have crashed it once and damaged the fairings.

I am in the air force and leaving for a deployment for 6 months, so today, I decided to start up the bike to put in some stabil in it. It took more than 30 minutes on choke and still couldn't get the bike to its usual idle without stalling, around 1500(never paid attention before, but defintely lower than 2000) . That was the first sign that something was wrong. Rode it around and it keeps stalling when it went below 2000. had to keep the choke on 2500-3000 for it not to stall. Eventually it didn't stall at 1500 anymore, but a lot of times when I apply the throttle the rpm fell and engine shut off. It seems that if it is around 2500-3000 it is OK. When it is OK around 1500, apply throttle, it goes up and stays up and goes down slowly. Played around with the carb adjuster, 1300-2000, it is about the same. I am not very mechanically inclined and will definitely get a mechanic to fix this.

What I want to know,is this a serious problem, is this is something I take to the mechanic right away? or can I wait until 6 months later. I was planning to just put Stabil in and just leave the battery charger on while I was gone. Is it crucial to change the oil now, or can it wait until I get back as well. Thanks everyone for reading.

[Motofool]

Originally Posted by ninja12345

...........What I want to know,is this a serious problem, is this is something I take to the mechanic right away? or can I wait until 6 months later. I was planning to just put Stabil in and just leave the battery charger on while I was gone. Is it crucial to change the oil now, or can it wait until I get back as well. Thanks everyone for reading.

Welcome to our site, Wendy !!!

Your problem seems to be deposits left by old fuel in the little passages of the carburetor.
That will not worsen in six months, so I would leave like it is now and the clean the carburetors upon your return.

The Stabil is OK, try filling the tank up with fuel because air inside is trouble for later.
You could drain the carbs, so some Stabil remains there softening some gunk maybe.

Replacing the oil is quick and very beneficial in order to avoid internal damage due to acids and water that are now dissolved in the old oil.
You could use any cheap oil and not replace the filter now if time is short for you.
You can drain that oil when you return and replace the filter.

Yes, leave the battery slow-charging and not in contact with concrete floor.

[csmith12]

Welcome! And thanks for your service.

[ninja12345]

I have added stabil. Can I also add some seafoam to it?
As for the oil, will car oil do? or it has to be motorcycle oil? I have some car oil sitting around.

[Motofool]

Originally Posted by ninja12345

I have added stabil. Can I also add some seafoam to it?
As for the oil, will car oil do? or it has to be motorcycle oil? I have some car oil sitting around.

I am not sure if it should be one or the other.

Yes, any clean oil will protect the internal parts during the winter.
Start the engine and make the new oil circulate some.
After that, you may need to add some to take it up to the correct level, which is about the center of the glass visor with the bike in vertical position and on both tires.

[jkv45]

Originally Posted by ninja12345

I have added stabil. Can I also add some seafoam to it?
As for the oil, will car oil do? or it has to be motorcycle oil? I have some car oil sitting around.

NO - car oil is not a good idea! Car oils have low levels of ZDDP that can cause damage to the cams in cycle engines. Changing the oil now is the best idea. After changing run it for 1 minute (to circulate the clean oil) and don't start it again until you are ready to ride. No need to change it again after storing.

Use any diesel oil. Diesel oils have safe levels of ZDDP and are generally high quality. The most common diesel oil used is Shell Rotella. The synthetic Rotella - T6 (blue bottle) - is a 5W-40 and is a good choice for all conditions. The standard Rotella T 15W-40 (white bottle) is good also, but only if you don't ride below 50 degrees or so - the 15W is too thick at those temps IMO.

If you've added Stabil, I wouldn't add Seafoam. I would add Techron Concentrate (1 oz per gal) to your first fresh tank after storage. I personally like it better than Seafoam, and it doesn't contain alcohol like Seafoam.

As far as your issues, the pilot jets are at least partially plugged. Before you leave, fill the tank to the top and open the drains on the float bowls to empty them completely. That way the jets won't get plugged any more. It's possible you can dissolve the deposits that are there with Techron, but it may need to have the carbs removed and the jets carefully cleaned. The easiest thing to do would be to drain the tank when you return and fill it with fresh 87 octane (no Ethanol if possible) and Techron Concentrate. If you can keep it running you may be able to move enough Techron through the jet to open it up. It could take a couple of tries, and it may not do it, but it would be worth a try.

Let us know when you are back and we'll help you get it going.

Stay safe and thanks for your service!


Jay

[red5]

Originally Posted by jkv45

NO - car oil is not a good idea!

I don't think he plans on long term operation with "cheap car oil". Just drain and refill now, then drain and replace with better stuff after the winter. Cheap stuff is fine for this.

[jkv45]

Originally Posted by red5

I don't think he plans on long term operation with "cheap car oil". Just drain and refill now, then drain and replace with better stuff after the winter. Cheap stuff is fine for this.

Still not a good idea. No reason to do 2 oil changes - cheap oil or not.

Just use decent oil like Rotella T6 and don't change it again in spring. The oil isn't going to "go bad" sitting in the engine during storage.

[ninja12345]

So I changed the oil and oil filter today. Turned out to be rather easy.
I started my bike today, but due to the rain, I did not ride.
After full choke for 5 minutes, it went down to about 3500 on idle. Adjusted idle to about 1500. The throttle response is way better than last week. When applying throttle, it goes up and down pretty good, it doesn't stay up and slowly go down. I don't know if it is back to normal yet. I will ride it when I get back.

Anyone have any explanation on what happened?
If all is back to normal when I get home, do I still need to take it in for carb cleaning?

Thanks everyone for reading and responding.
I also appreciate the support for the troops.

[ninja12345]

Another question for everyone:
what is a typical cost of carb cleaning by a mechanic? independent and dealer?
Thanks again.

[Motofool]

Originally Posted by jkv45

.........The oil isn't going to "go bad" sitting in the engine during storage.

I may be wrong, but I believe that, same as happens inside the fuel tank, humidity in the air condenses over the metal walls with each cycle of temp and humidity variation (if the bike is exposed to outdoor conditions or not started during the whole winter), condensate flows down to the bottom of the crankcase and stays there waiting for the oil pump to suck it and send it to the bearings at the first start up.

This condensation normally happens a little everyday, but with the regular use of the bike and the engine reaching operational temp, that humidity is vaporized and vented via crankcase vent.

I forgot mentioning covering the wall cylinders with some protection injected via spark plugs' holes after the engine is finally stopped:

http://faq.ninja250.org/wiki/How_sho..._than_6_months

[jkv45]

It's not the same situation with the oil as it is with the gas. Any condensation will sit on top of the oil.

Synthetic oil has advantages over conventional oil when it comes to oxidizing from exposure to air - as it has a close molecular structure. Fresh oil sitting in the sump over the winter won't degrade enough to need to be changed in spring. The fresh oil coating the cams and internals of the engine creates a barrier that prevents corrosion. Used oil contains acids, gas, and water which increase the chances of corrosion.

In normal use, the oil is constantly exposed to moisture from running and cooling. Once the engine reaches operating temp the moisture will evaporate - given enough time. That's why you should never start an engine during storage to "warm it up" - you are creating moisture and mixing it into the oil (along with gas and acids) but idling or moderate running will not allow the oil to reach operating temp quickly enough or for a long enough time to evaporate the moisture you just added - so all you've done is contaminate your clean oil.