After warm up, moving off of choke stalls engine

[ricomtzjr]

Elev. 3800ft
Temp. 30-60*
Hum. 20-30*

2012 250: 2300 miles

Snorkel removed, 2 washer shims.

This only happens when warming up the engine. At first, I thought it was just not warming up long enough for 30* mornings, but this happens during my he day @ 60* as well. I'll use about 75% choke to start and even if I slowly back the choke off it stalls once choke is completely disengaged. I am beginning to think 2 washers is a little rich for the temps this season. Thinking of going to 1 washer. Any thoughts?

[Motofool]

I don't think that the washers are your problem, since they allow more fuel during acceleration.

Your mix is lean: too little fuel + too much air

While the engine is hot enough, less fuel condensates on the cold metals of the intake and less mass of air can be aspired, moving the mix toward the proper ratio.

The opposite happens while the engine is cold, having the choke supplying extra fuel into the mix.

Your jets may need a good clean up.
In the meanwhile, I would replace the snorkel.

[ricomtzjr]

Then I will try one more washer. Dont really feel like trying to put the snorkel back on. It was a PITA when I tried before I shimmed the needles. Hence why I shimmed instead of reinstalling it. I will see what happens today. It's really windy and cold outside.

Being that I just took this off the showroom floor in October, should I really consider cleaning the jets? I bought this bike new Oct 3. and use it very frequently. Maybe a fuel additive, say Seafoam, to do the trick on a newer low mileage bike?

[DaBlue1]

Originally Posted by ricomtzjr

....
This only happens when warming up the engine. At first, I thought it was just not warming up long enough for 30* mornings, but this happens during my he day @ 60* as well. I'll use about 75% choke to start and even if I slowly back the choke off it stalls once choke is completely disengaged.

If when you take the choke off and it stalls, the engine is still cold. When sufficiently warm the engine should be able to maintain idle without the choke. You can ride off with the choke on for a short distance if necessary to help bring the engine temp up (especially in freezing temps). When the idle speed is set correctly, it should be 1300 rpms (+/- 50 rpms).

Another thing you may want to take into consideration is possible carb icing.

[ricomtzjr]

Originally Posted by DaBlue1

If you when you take the choke off and it stalls, the engine is still cold. When sufficiently warm the engine should be able to maintain idle without the choke. You can ride off with the choke on for a short distance if necessary to help bring the engine temp up (especially in freezing temps). When the idle speed is set correctly, it should be 1300 rpms (+/- 50 rpms).

Another thing you may want to take into consideration is possible carb icing.

So how will I know if this condition is happening here? Still new to carbs, so my knowledge about specific conditions is still limited.

[Motofool]

Originally Posted by ricomtzjr

..........Being that I just took this off the showroom floor in October, should I really consider cleaning the jets? I bought this bike new Oct 3. and use it very frequently. Maybe a fuel additive, say Seafoam, to do the trick on a newer low mileage bike?

Jets should be perfectly clean; fuel additive is not necessary.

Keep the two washers and keep the choke for longer time, until the engine asks you for less rich mix (you will feel it).

http://faq.ninja250.org/wiki/What_is..._at_startup%3F

Sorry, I don't really understand what is the reason behind removing the snorkel.
It is like we assume that we know better than the Japanese engineers.