250 ninja help!!

[spots25]

Okay, so its not a GS, but you guys are awesome, and any pointers are helpful. I got a 03 250 ninja the other day to ride while the GS was in construction, and it won't idle off choke. I cleaned out the carbs and it didn't change. It also won't rev when the choke is partially on like it should. It really feels like the idle mixture screws aren't letting enough fuel in, but I have them turned back to baseline and it doesn't help. Any suggestions?

Thanks

[U.P.dragracer]

8-[ those carbs have to be surgically clean !!! the pilots are so small you can't hardly see through them when they are clean . the main jet tubes {emulsion} have to be spotless as well . any dirt at all will render the 250 ninja dead in the water .
I have had brand new 250 ninja'sout of the crate that needed a carb clean :shock:

[oldschoolorange]

Yeah I second the advice to make sure the insides of the carbs are spotless, use compressed air if you can. In my experience with the 250 ninja the engine has to be hot before it likes to rev as well

[spots25]

earlier today I took the idle mixture screws out and sprayed carb cleaner in them. After the first one, there was no change. After the second, it wouldn't start, and black flakes starting coming out of the exhaust. I tried pulling the idle mixture screw out again and a chuck of black flake was in the spring. I guess I'll have to take them out again

[earlfor]

Spray carb cleaner is intended to be sprayed through the passageways on a carb after it has been disassembled and all the plastic and rubber parts removed. I dont know of any spray carb cleaner that does not dissolve rubber seals/parts and plastic.

Earl

[spots25]

its not a rubber flake, its a carbon buildup flake.

[txironhead]

Spray carb cleaner is intended to be sprayed through the passageways on a carb after it has been disassembled and all the plastic and rubber parts removed. I dont know of any spray carb cleaner that does not dissolve rubber seals/parts and plastic.

Earl

If it sits on the rubber or plastic then yes, it will dissolve them, but a quick spray normally doesn't hurt. I learned the hard way, that master cylinder really didn't need a new plunger when I started.......

Those carbs need to be thoroghly disassembled and cleaned and verify that the tank is clean as well as the petcock filter if so equipped. Compressed air and fishing line will help clean the tiny ports.

[bradleymaynar]

Spray carb cleaner is intended to be sprayed through the passageways on a carb after it has been disassembled and all the plastic and rubber parts removed. I dont know of any spray carb cleaner that does not dissolve rubber seals/parts and plastic.

Earl

From what I've read on the directions. Carb cleaner can be used in two ways. One is to be used when cleaning carb parts while they're disassembled. The second is to use it as a quick fix and to fog the carbs while the bike is running in order to clean up any residue.

Brad bt

[U.P.dragracer]

earlier today I took the idle mixture screws out and sprayed carb cleaner in them. After the first one, there was no change. After the second, it wouldn't start, and black flakes starting coming out of the exhaust. I tried pulling the idle mixture screw out again and a chuck of black flake was in the spring. I guess I'll have to take them out again

that black flake in the mixture screw spring is most likeley damaged o-ring :shock: the mixture screws have a spring , metal washer , and o-ring inside the carb . if they are damaged pieces of the o-ring can plug up the carb and leak air as well . in either case the 250 ninja will not run worth crap 8-[

[spots25]

that black flake in the mixture screw spring is most likeley damaged o-ring :shock: the mixture screws have a spring , metal washer , and o-ring inside the carb . if they are damaged pieces of the o-ring can plug up the carb and leak air as well . in either case the 250 ninja will not run worth crap 8-[

hmmm... i never got an o-ring out of the hole the first time. I hope thats not the case, but I guess i'll look more closely this time around... if there was an oring hiding way back there, how would I get it out?

[Schweisshund]

Spray carb cleaner is intended to be sprayed through the passageways on a carb after it has been disassembled and all the plastic and rubber parts removed. I dont know of any spray carb cleaner that does not dissolve rubber seals/parts and plastic.

Earl

Seafoam Deep Creep - cleans carbs and lubricates rubber

[txironhead]

hmmm... i never got an o-ring out of the hole the first time. I hope thats not the case, but I guess i'll look more closely this time around... if there was an oring hiding way back there, how would I get it out?

Dental pick, stiff wire with a small bend in the end, or a toothpick.

[U.P.dragracer]

hmmm... i never got an o-ring out of the hole the first time. I hope thats not the case, but I guess i'll look more closely this time around... if there was an oring hiding way back there, how would I get it out?

I use the carb spray tube LOL get it in just right and it will blow the o-ring out and it will slide right down the tube so you don't lose it . don't forget the metal washer when you put it back together .

screw, spring , metal washer , o-ring insert into carb 8-[

[spots25]

wow, i'm a little embarrased. I've never taken apart this kind of carb before, and never bothered thinking or looking in any sort of repair manual, but out of the 2 carbs, I only had 1 oring and no washers I feel really dumb, but I guess I assumed since none came out that there wasn't any.

I guess I'll get them tomorrow, since by some unknown law, NO motorcycle shop in the world is open on monday

[txironhead]

That actually came from the days of factory-sponsored races. The races are held on Sunday, and Monday was used for repairing the bikes and recuperating. Not many dealerships still sponsor racers, but the tradition has carried over.

As for those parts, it's unlikely you'll be able to buy those pieces seperately. Chances are you'll have to buy the entire carb rebuild kit, and even then it may not come with washers. You might check out www.bikebandit.com and see if they sell the pieces individually. They have good exploded diagrams which can also be helpful. You might try to find comparable washers at an auto parts store, but you have to make sure it's the exact size and rated for gasoline. The washers may be tricky to find, but you may get lucky.