Ninja 250 stalling

[Image5050]

Ok here's the deal. I've got a 2010 250 I bought a couple weeks ago with 1800 miles. It's warm where I live and my bike starts up with no choke just fine and idles ok. Set idle to 1600rpm. When I take the bike out for a ride it does fine, power feels good through all ranges. After all warmed up, if I stop the bike for a couple minutes, the rpms slowly start to fade until the bike stalls and dies. I posted this in another forum and didn't get too many replies. Is this a problem with the carbs? Could they be dirty? I checked the air filter and it looks good....

Quick update: I haven't ran the bike for prob 6 hours or so. I went out and started it(easy) and let it idle. Idled beautifully at 1500rpm for around 4-5min and slowly died off. WTF???
Could start it again, but slowly dies off each time. Revs up just fine.

Please watch this video and HELP!!! http://youtu.be/WHLyVrd8WrY

[xSean13]

If in doubt, seafoam.

inb4jiggles.

[Image5050]

Ah yes, I actually just put some in there this morning. How long should I run it before I expect to see any results? Should I use the 1oz to 1 gal ratio or put the bottle in with a full tank of gas?

[Image5050]

http://www.youtube.com/watch?v=WHLyV...e_gdata_player

[alex.s]

it looks like a minor vacuum leak.

[Image5050]

You guys think my "good times" warranty would cover that? I know it's hard to tell without prob just calling them

[alex.s]

if the warantee is still good, i would think the entire vacuum system and carbs (minus cleaning) would be covered.

you can tell its not a low idle or clogged jets because it idles for a bit at 1250 correctly (well- the carbs aren't synced) then you notice after a few seconds one of the cylinders starts quieting down. the leak is probably on that carb somewhere. the gas is pulled into the carbs by engine vacuum from the tank, controlled by a float valve like in a toilet. if the vacuum lines have a leak, it cant pull as much gas with the same amount of vacuum. when you are at idle the vacuum pressure is low, and its not enough to keep the carbs filled with the vacuum leak. the level in the carbs gets too low and it starts to die.

just my opinion.


try spraying something flammable like carb cleaner or starter spray near your carbs. the vacuum leak should pull it in and the engine rpm will pick up a little bit. ... if there is actually a vacuum leak

[Image5050]

Thank you for such a thorough reply. Sounds like you know what you're talking about. I'll try spraying some cleaner in there and see what happens.

[Image5050]

I'll have to wait until I'm off work in the morning to try spraying the carb, but say my warranty wouldn't cover that service for whatever reason. How difficult would that problem be for me to try and correct? Is it as simple as taking off a vacuum line and replacing it?
Can that be done with the carb on the bike?
Thanks again.

[alex.s]

if it is a leaking vacuum line: easy, yes and yes.

[Image5050]

Well, I just went out and started up the bike. Fired up fine, as i usually does. As it sat there idling, I sprayed carb cleaner around the vacuum hoses and the carb in general and didn't notice any increased idle speed. I tried this several times listening carefully. Again, as usual, the idles finally died down and the bike stalled. The bike is always a bit difficult to start after that, so I thought why not try the choke. I turned it all the way on and it fired right up. I let it run for a while and slowly took it off. Once the choke was off, it idled for a short bit and did the same thing, dying off slowly. Does the use of the choke help with your diagnosis any?

Also after watching youtube and reading around a bit, it seems that nobody has to give the bike any throttle to start it. It seems like I always have to give it slight throttle as I start mine up. Doesn't matter if it's warmed up or cold.

[alex.s]

hmm if you turn the idle up to say 1750 or 2000 will it still die?

if it doesnt die idling at 2000 (beginning to open the needle valve), your pilot jet is probably just dirty, run a tank with seafoam in it and if its still wont idle at 1250 after that tank of gas+seafoam, maybe try cleaning the jets themselves.

it idling fine with the choke on is interesting. its an enricher circuit not a real choke so its adding fuel to the mix which agrees with a dirty pilot jet theory. needing some throttle to start also kinda agrees with this. of course its possible your idle setting is just too low

i would warm it up then play with the idle setting first. see what idle it takes before it keeps itself from dying.