Strange problem with bike starting

[scorch]

i was hoping that someone could help me with my ninja 250(2002). It has roughly 45k miles. But always had a hard starting problem. Specially when it gets cold.

New battery, voltage is great. But in the morning it takes forever to start, 20 or so tries. The cranking is fine, but just wont engage easily.

If i start it, and use choke. It starts for maybe for 3 secs, then dies. And then its tough to get back.

I've cleaned the carbs throughly

the electrical seems ok, without any grouding issues i can tell. No serious mods to the bike at all.

In hot temps it seems fine, it starts easy. But as soon as the temps dip a little it just becomes a bear to start.

Anything i could look into?

A friend suggested the solonoids? Or a carb issue.

It seemed to be a battery issue, but its not that at all.

[dcj13]

Are choke cables adjusted so they close to the fullest extent?

[scorch]

Yeah chokes cables are fine.

[TnNinjaGirl]

When was the last time the valves were checked?

Bike runs normally when started? Idle is nice and solid with no wavering?

[scorch]

Originally Posted by TnNinjaGirl

When was the last time the valves were checked?

Bike runs normally when started? Idle is nice and solid with no wavering?

I adjusted them about 500 miles ago. I usually put them mid spec.

The bike runs really well when its warm, and starts easily when its warm.

Rides really well too.

[TnNinjaGirl]

Did you notice a difference in starting after you checked your valves?

[scorch]

Not at all, even with the valves adjusted it was always like this when i got the bike.

It was hard starting before. I had a 08 ninja and that never had a problem starting, a friend with a 2006 ninja doesnt have the same problem as well, his starts easy no matter the temp.

[dcj13]

My '03 started just fine at all temps (still does!). Occasionally it took two attempts.

[TnNinjaGirl]

Stock size jets? OE Exhaust and air filter?

[cuong-nutz]

Tell me more about this new battery.
Was this the kind where you have to charge it before you use it?
The kind where you have to fill it and seal it?
The kind that you got from a bud and is new to you?

If any of the above, have you had it load tested? Reason I ask because there are times the batteries are bad from the manufacturer with a bad cell or two. Although it may show good voltage, you will notice it that it won't have enough juice to start it. If you see the voltage drop below 10 Volts than more than likely you have a bad cell or two.

Other scenario is just bad spark plugs or bad compression.

[spooph]

@scorch! Halo! What happened to your red '08?

Concerning this one, my first though was spark, as Cuong mentioned. Cold means metal contracts, and if there is a worn contact in the wires this is an easy place for the spark to get lost.

Have you verified the entire spark system? Plugs, boots, wires, coils, coil caps, energizer leads to the coils?

What specifically do you mean by "The cranking is fine, but just wont engage easily."?

As in, it cranks but it doesn't fire easily. It sputters, pops and such?

Also, have you checked the tank vent? Does it change at all if you open the gas cap?

[ducatiman]

Originally Posted by scorch

If i start it, and use choke. It starts for maybe for 3 secs, then dies. And then its tough to get back.

I've cleaned the carbs throughly

If I may suggest a revisit to the carbs....the enrichener or starter circuit, whatever you'd like to call it.....specifically the "starter jet", "choke jet" or pickup (as its not a removable jet, see attached pic ). I surmise something is clogged there, a fuel delivery issue within that circuit.

take a guitar string maybe a .014 or .015"? Can't remember size...but give it a poke...the string should easily insert 1.5 inches or so. If not, it may be clogged. Poke it with string, carb cleaner, compressed air, ultrasonic, whatever it takes.
Note each carb identical so check both.

Next...at the base of the pickup orifice there is an open hole....assure that is open. blowing air in should reveal a stream exiting the brass pickup (jet). Using your fingers to feel should reveal stream.

Next...removing a choke piston from the carb reveals a chamber leading all the way to the pickup/jet. Thats the full choke circuit....again, compressed air and fingers to "witness" it is clear. Heated ultrasonic works really good clearing this circuit, they can jam up solid.

I'll see if I can add a pic (from EX500 carbs) the 250 uses same circuit. Here you are...all the way on the left marked "choke jet".

Good luck with it.

[alex.s]

sounds like stuck petcock valve

[f0r54ken]

It sounds like you know what you're doing too. So i'm gonna throw out some of the random wacky possibilities.

Which oil displacement are you using? Just curious to know the grade. like 10/40 or 20/40. Maybe it's too thick starting?

Antifreeze in the radiator right? Not water? I just imagine the water freezing inside the pipeline. Lol

are the tubes and hoses plugged back into the right spots on the carb?

is your idle set to summertime? Like low (Once it's on). Cause I know when it's cold you're idle knob just needs to be a bit "higher" in general.

For some reason I imagine your fuel isn't rich enough. Like it's getting more air than it is fuel. At least that's been my cold experience.

I see the other members suggest checking the sparks as well. If you want to know for sure if the spark plugs are working, This is a little wacky But I like to test it by taking the spark boot and plug together one at a time and holding it in my hand (Other spark plug not plugged in.) Hit the ignition and see if you get shocked a couple times. Then again with the other one.

IF you check all that then it's gonna be beyond my "expertise" lol but I hope you get it fixed make sure if you do you let everyone know too cause I get the feeling with winter approaching we're gonna see a bit more of this.

[scorch]

Hi Spooph, how are you? I sold the 08 a while ago. It had 87k miles and i thought it was time to go. Still have my 02.

Thanks for the help guys, i been slow to get it working. But ill keep you guys updated shortly.

Originally Posted by spooph

@scorch! Halo! What happened to your red '08?

Concerning this one, my first though was spark, as Cuong mentioned. Cold means metal contracts, and if there is a worn contact in the wires this is an easy place for the spark to get lost.

Have you verified the entire spark system? Plugs, boots, wires, coils, coil caps, energizer leads to the coils?

What specifically do you mean by "The cranking is fine, but just wont engage easily."?

As in, it cranks but it doesn't fire easily. It sputters, pops and such?

Also, have you checked the tank vent? Does it change at all if you open the gas cap?