I have a problem KTM 250SX

[jtm994]

Today i went to fire up my 05 ktm 250Sx that i bought about 2 weeks ago and it took about 6 kicks to fire up. I usually starts right up with 1 or 2 kicks. Then i took it down the street and when i give it gas it jumps and acts like it wants to go but wont. Then when i was comming back home it just cut completely out on me and will not fire up for anything. It had quite a bit of spooge up under the rear fender. The gas is in it from when i bought it. The guy i bought it from says he olny rode it once. I do not know the mix ratio he was using. help

 

[jtm994]

UPDATE: I went and changed the plug out. Fired up first kick but smoke was pouring out of the pipe. It has to do with the mix ratio right? should i drain the gas a start over with a fresh batch and see what happends? If was what ratio should i use?

 

[Moose]

You fouled a plug. Get your bike jetted. What mixture are you running?

 

[jtm994]

You fouled a plug. Get your bike jetted. What mixture are you running?

I just bought the bike and the prev. owers gas is in there. What mixture do you suggest?

 

[Moose]

Were you running it hard, or just putting around?

 

[jtm994]

Were you running it hard, or just putting around?

When I fouled the plug just putting around. I am going to use redline oil. They recommend 50:1. Does that sound good? KTM recommends 40:1 - 60:1

 

[rmc_olderthandirt]

My first recommendation would be to drain the gas and replace with something you know. No telling how old that gas in the tank is.

Do you have buddies that you are going to ride with, and do they ride two stroke? If so, then I would recommend using the EXACT same oil and mix that your buddy does, as long as it is in the appropriate range for your bike. This will allow you and your buddy to share gas without any concern.

Once you establish an oil and mix ratio then go through the effort of getting the carburetor jetted properly. Changing the oil mix will change the jetting requirment, so you want to choose one, jet for it and stick with it.

Rod

 

[jtm994]

My first recommendation would be to drain the gas and replace with something you know. No telling how old that gas in the tank is.

Do you have buddies that you are going to ride with, and do they ride two stroke? If so, then I would recommend using the EXACT same oil and mix that your buddy does, as long as it is in the appropriate range for your bike. This will allow you and your buddy to share gas without any concern.

Once you establish an oil and mix ratio then go through the effort of getting the carburetor jetted properly. Changing the oil mix will change the jetting requirment, so you want to choose one, jet for it and stick with it.

Rod

Everyone i ride with rides 4 strokes which i do to but i just recently bought this 2t. but how would you know if the bike needs jetting? will it smoke to much, foul plugs, or what?

 

[ZOMBIE666]

if its smoking a good bit, your jetting is too rich or your pre mix is way rich with oil/ bad gas

if its smoking way too much clutch side crank seal may be bad.

a rich condition would cause the spooge and plug fouling especially if you were just putting around.
like the others said, drain your gas, put in a fresh plug and fresh premix.- .

if your going to do the jetting yourself remember, rich just kills your plug, lean kills your bike

 

[Moose]

If you were putting around, then that's why. If they aren't ran hard enough, they'll foul.

 

[dezryder]

Hmmmmmm

If you were putting around, then that's why. If they aren't ran hard enough, they'll foul.

I don't think so. :coocoo:

To the OP: My 250 KTM has always been really picky about the gas it wants to burn. If is even slightly on the old/stale side that bike will just wet-foul plugs, smoke like crazy and make itself almost impossible to start until you give it some new gas!

 

[Moose]

oh, my mistake then. i was always under the impression that if 2 strokes weren't ran to a certain extent, that they'd foul.

so is there another reason as to why my bike fouled a plug when I was just learning. i did not get out of second gear while learning, yet the next time i went riding i used the same gas, same type of plug, with no problems. :think:

 

[dezryder]

oh, my mistake then. i was always under the impression that if 2 strokes weren't ran to a certain extent, that they'd foul.

so is there another reason as to why my bike fouled a plug when I was just learning. i did not get out of second gear while learning, yet the next time i went riding i used the same gas, same type of plug, with no problems. :think:

I can't answer that because there could be any number of reasons you fouled a plug.

I can say with confidence that a properly running two stroke motor can chug around all day long without fouling plugs though. :nod:

 

[jtm994]

if its smoking a good bit, your jetting is too rich or your pre mix is way rich with oil/ bad gas

if its smoking way too much clutch side crank seal may be bad.

a rich condition would cause the spooge and plug fouling especially if you were just putting around.
like the others said, drain your gas, put in a fresh plug and fresh premix.- .

if your going to do the jetting yourself remember, rich just kills your plug, lean kills your bike

I am running 40:1 now and its still has alot of spooge. Is there a certin jet that controls the spooge or do they all?

 

[skiboyracing]

IMO, Run the bike until it's up to temp and cleaned out. Then put a new plug in it and run it wide open through all 5 gears and hit the kill switch while you are stopping. Get off and pull plug right there in the road. If it's all wet and/or black, drop down 1-2 sizes on the main and see what it does. If it's white then go up on jets. The plug should be dry and the porcilin should just be turning a nice brownish color. Your probably going to get some spooge on a 2t regardless but you should do a plug reading to get your a/f correct. I wouldn't go any leaner than 40:1. Personally I like 32:1