2007 ninja 250 HELP ME GET IT RUNNING

[mjsyard]

a friend gave me his ninja 250 because he moved. It had sat for over 1 year and would not start. My neighbor cleaned the carbs for me twice but it still isn't running. It will start but the idle is very weak and it will stall if i take the clutch off. any suggestions???

[Yarhj]

First off, here are some good resources to get you started:
Troubleshooting
Things to look for if your bike won't start

And now, some questions.

You say it starts, but stalls when you let out the clutch, right?
1. Are you using the choke when starting it?
3. Does it run indefinitely if you start it in neutral and just leave it that way, or is it always trying to stall?
4. Roughly what RPM is it idling at?
5. Has the battery been charged? If the bike has been sitting that long, it may be a bit weak.
Battery troubleshooting info

[Racer x]

First thing I would do is replace the pilot jets. The rotten fuel corrodes them closed. You just can't clean them

[Yarhj]

Originally Posted by Racer x

First thing I would do is replace the pilot jets. The rotten fuel corrodes them closed. You just can't clean them

I let my bike sit for about a year with unstabilized fuel in it, and all the pilot jets needed was a little scrubbing with some copper wire (as per these guides), along with the transition circuit openings. There's really not much that can go wrong with the jets themselves in only a year, beyond getting a bit gummed up with fuel varnish.

[Racer x]

I have seen pilot jets that needed to be drilled with a micro bit after only sitting over the winter. Ethanol will make a mess.

[jkv45]

Depends on how the carb was "cleaned". There are a lot of specific things that need to be done to make sure all important parts (like the jets) of the carb are completely clean.

Did you completely drain the tank and refill with fresh gas? If not, you need to. Drain the float bowls also. If that doesn't help then the carbs most likely need to come off and be cleaned thoroughly.

[mjsyard]

so the carb was put in a sonicator to clean it. It looks pretty much spotless but i am not sure about the jets. I am going to try and pull it this weekend. I have heard that running guitar strings through the jets will help clean them and open them up. Anyone else tried this?
the old gas was drained and fresh added.
it starts with clutch on only and rpm's less than 1000. if i give it gas or turn off the clutch it dies.
it has a brand new battery.

thanks everyone for your suggestions......

[Yarhj]

A sonicator should do a decent job of getting rid of gummed up fuel, but the small passages in the pilot jet, and especially the tiny holes in the transition circuit (those tiny holes underneath the butterfly valves) could conceivably still have crud in them. A guitar string or some fine-gauge copper wire are commonly used to clean those out -- it's kind of like flossing, but for your carbs!

I'm thinking it's an issue with the pilot jet, since it dies when you crack the throttle -- if the pilot jet is a bit plugged up, the mixture will get too lean when you open the throttle. I don't think stalling when you let out the clutch in gear with no throttle applied is anything to worry about -- pretty sure my bike will die if I just let the clutch out at idle in 1st gear (especially if I do it right after starting it cold!).

Since it does start, you could also try just starting it in neutral and letting it idle for a few minutes before trying to give it any throttle input. As long as it's idling, gas is flowing through the carburetors, and if there's some old fuel residue it may just get dissolved as the new fuel flows through. If idling it for a few minutes doesn't clear it up, you could also try adding a bit of seafoam or techcron or some other fuel system cleaner to your gas, and then letting it idle for a few more minutes.

If none of that works, you could also check that the mixture screws on each carburetor are set to ~2.5 turns out (screw them all the way in, lightly, but don't force them when they stop turning! Then turn them back out 2.5 full turns [900 degrees]).

Keep us posted with what you try, and good luck!

[flitecontrol]

Not sure what solvent you used in the sonic cleaner. I use Berryman's Chem Dip and monitor it closely because the sonification process produces heat and Chem Dip is flammable. In my experience, it cleans all the metal parts, including the jets, very well. Just rinse with water and blow out every orifice in the carbs with high pressure compressed air (very important) when finished.

I know lots of folks run steel guitar strings through brass jets, but I've always been concerned that the guitar string could enlarge the openings in the jet assembly. Those openings are critical to proper functioning of the carb, and should not be altered.

[Yarhj]

Originally Posted by flitecontrol

I know lots of folks run steel guitar strings through brass jets, but I've always been concerned that the guitar string could enlarge the openings in the jet assembly. Those openings are critical to proper functioning of the carb, and should not be altered.

Good point -- if you're using guitar strings to clean out the passages, use nylon, not steel! Copper wire should be fine, as copper is softer than brass.

[agentbad]

Do you mean turn the choke off or does the bike die when you release the clutch? If it's dying when you release the clutch that could indicate a dirty safety switch either at the clutch lever or the kickstand switch. You can usually work it free with a little WD-40. Does it idle when it's in neutral? If that's not it then you need to take the jets out and clean them with some small gauge copper wire. Set the idle knob a bit higher on the side of the bike. Hold them up to a light or the sun to make sure all the little holes are clear.

http://i.imgur.com/YE4xpxH.jpg

[mjsyard]

so i have cleaned the carbs....went to a bike shop and had them look at them and they said they are good.(including pilot and main jets) now i am putting it back together and whoops....can't figure out which throttle cable goes where. i believe one is an accelerator and maybe one a decelerator??? any one got a idea for me. (photo would be great) i need to know where they attach on the carbs?

[Yarhj]

One of the cables is the choke and the other is the throttle. The choke cable should be coming from the left side of the bike, and the throttle should be on the right. If there's any confusion, just twist the throttle grip -- the cable that moves is the throttle cable.

As to how they're hooked up, the throttle cable connects to the right side of the choke -- there's a little metal cylinder on the end of the cable, and it slots into the throttle cable bracket on the right side of the carburetor.

Take a look at this picture to see where that bracket is (top left in this picture) -- in this case we're looking back at the carburetors from the perspective of the engine, so the right side of the bike corresponds to the left side of this picture.

The choke cable slots into the choke cable bracket in much the same way. It's not called out explicitly in the picture above, but it's the metal piece directly above the carb sync adjustment screw in the picture -- that meta bracket slides left and right -- try pulling it one way and the other and you'll see how it works.

If you play around with the cables and the brackets you may be able to figure out how they go together. If it's still not making sense after that, I can take some pictures of my bike tomorrow.

[mjsyard]

thanks the picture was perfect...i do have one more question...the screws on the cable at the brackets...is there a specific amount of times to screw the top screw and what about the screw below the bracket. sorry i am just a beginner.

[agentbad]

Originally Posted by mjsyard

thanks the picture was perfect...i do have one more question...the screws on the cable at the brackets...is there a specific amount of times to screw the top screw and what about the screw below the bracket. sorry i am just a beginner.

Huh? Just screw that bad boy back on until it's tight.

[Yarhj]

I'm not sure which screws you're referring to -- if you post a picture or point them out on a picture someone's already posted (or a youtube video or something) then I can be more specific. There's at least one screw for the throttle cable bracket, and for that one you can just screw it in until it's tight. You can pretty much do the same with any other mounting screws on the carburetors (within reason -- if you find yourself using two hands to tighten a screw you've gone too far), but don't mess with the carb sync adjuster screw (the one with the yellow paint on it) unless you're ready to sync the carburetors. It would be a good idea to sync the carburetors after you get everything reinstalled, and it's not hard to do, but it's not necessary to do it right away, if you're just not up to it.

[mjsyard]

okay so thanks to everyone it is starting but now the throttle is sticking (i think) well it is warming up the rpms go up really quick like the throttle is being moved. i heard this can be due to the floats not being set properly or the carbs need synced.....ANY OPINIONS???

[Woolley7325]

Is your idle adjust knob turned up too high? Or maybe too much choke?

[jkv45]

Originally Posted by Woolley7325

Is your idle adjust knob turned up too high? Or maybe too much choke?

What happens if you back the choke off once it's running?

You should be able to back it down enough to just keep it fast-idling about 2000 or around there.

Keep backing it down as much as possible as soon as possible. No need to let it idle for too long, you can ride it with a minimal amount of choke (enrichener) still on, and turn it off completely within a minute or two.

[DaBlue1]

Another rider recently had a very similar problem. His idle adjustment knob was screwed in too far. See this thread for the fix information- Idle shooting WAAY up on start