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Posted

Hello

I have a 78 dt250 and a couple days ago i was riding it around on the streets and it just shut off and now it wont turn back on. I have checked the spark and it is getting good spark there is fuel going to the carb and nothing jammed in the air filter. When it died it seemed like it was out of gas but before i rode i had top the tank off. I know the bike might have some bad wirring do yal might think that something shorted out? Any info would be great i miss riding the bike.

Cliff notes.

Took the bike out rode around and it shut off. Now it wont turn over, Checked the Fuel air and spark and made sure that it wasnt on engine off and it wont turn on.

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Posted

Hello

I have a 78 dt250 and a couple days ago i was riding it around on the streets and it just shut off and now it wont turn back on. I have checked the spark and it is getting good spark there is fuel going to the carb and nothing jammed in the air filter. When it died it seemed like it was out of gas but before i rode i had top the tank off. I know the bike might have some bad wirring do yal might think that something shorted out? Any info would be great i miss riding the bike.

Cliff notes.

Took the bike out rode around and it shut off. Now it wont turn over, Checked the Fuel air and spark and made sure that it wasnt on engine off and it wont turn on.

Do you mean the engine will not kick over. Is the kick starter still turning the engine over.

  • Moderator
Posted

Do you mean the engine will not kick over. Is the kick starter still turning the engine over.

It must be TS, the poster said it has a good spark....cant say this with a siezed engine!

Posted

It must be TS, the poster said it has a good spark....cant say this with a siezed engine!

True, but in his "Cliff notes" He says "Now it won't turn over" I quess you see where I was going.

  • Moderator
Posted

Yes, we need some clarification.

Has fuel, has spark? that leaves timing which is generally ok if you have a fat spark.

Could have pinched and done the rings or holed the piston. Wodruf key gone, used to tool about on a Maico 490 (one scary motorcycle) with some of my mates and that sheared them so often we had some with us when we went out.

Posted

the kickstart still cranks the motor but it just wont turn on, its like it just doesn't want to start. It does have a nice spark when I kick it; I checked the compression on the head and its at 40psi, is that good or bad? I looked and i can't find anywhere what it should be...

  • Moderator
Posted

You say it has fuel, do you mean there's fuel in the tank or the spark plug is wet with fuel? If the plug is not wet with fuel you need to

1 Verify a good flow to carburettor

2 Strip carb and check the pilot jet isn't blocked

Posted

I have pulled the fuel line off where it connects to the carb and turned the flow on and gas came out so its getting to the there. Also, I have have pulled the cap off the carb where the throttle line goes into it,because the throttle cable recently broke and I replaced and I noticed the the plunger and jet needle were both pretty wet with gas so I'm not to sure if that would be the problem. Could the fuel be getting blocked somewhere else? maybe in the bowl or something? I dont know. Another thing, how would I check the timing? do I have to pull the head off and check the chain and where is it supposed to be at? Third, I dont know what a TS is, sorry I'm still new to bikes can you elaborate on that. and finally would anything in my wiring cause something to short out and make the bike die like that because like I said in the first post the wiring is kind of rinky dinky. Sorry for so many questions guys, I'm just totaly lost on why it would do this. Any and all help is appreciated

Posted

I have pulled the fuel line off where it connects to the carb and turned the flow on and gas came out so its getting to the there. Also, I have have pulled the cap off the carb where the throttle line goes into it,because the throttle cable recently broke and I replaced and I noticed the the plunger and jet needle were both pretty wet with gas so I'm not to sure if that would be the problem. Could the fuel be getting blocked somewhere else? maybe in the bowl or something? I dont know. Another thing, how would I check the timing? do I have to pull the head off and check the chain and where is it supposed to be at? Third, I dont know what a TS is, sorry I'm still new to bikes can you elaborate on that. and finally would anything in my wiring cause something to short out and make the bike die like that because like I said in the first post the wiring is kind of rinky dinky. Sorry for so many questions guys, I'm just totaly lost on why it would do this. Any and all help is appreciated

It could be a number of things, If you were close to me I would help you out.

Posted

I'm in San Antonio if your close come on by and give me a hand. If your not a few pointers on what to look out for would be just as helpfull

Posted

Well i just got a chance to work on it. Put a new plug in and still nothing. The plug does not get wet so i took the carb out and stripped it and the jets are not clogged nothing really in there to make me think there is debris in there. I tested the plug and i still had a nice spark when i unplugged it and had it lay on the head.Does anyone know what the Compression is on these motors? I have no clue what it could be. Would having a Bad kill switch not let the bike start? I dont know where or what to check anymore. Any other reason why my spark plug wont get wet with fuel?

Posted

Ok i just tried push starting it and Nothing. It would turn over and Start for like a Brief secound and shut off right away. I tried giving it gas and it does nothing. Would a Video help anyone out with trying to find the problem?

  • Moderator
Posted

Ok i just tried push starting it and Nothing. It would turn over and Start for like a Brief secound and shut off right away. I tried giving it gas and it does nothing. Would a Video help anyone out with trying to find the problem?

These things can be difficult to find weve all been there, how long have you owned the bike? what do you know of its history, who put the fuel in...you?

Posted

Just got the bike like maybe a month ago. Bought it and it would start right up and drive fine my brother and i would drive it around alot. I put the gas in at a Shell gas station ran about two tanks thru it. And one day i went to ride it around the block and it shut off on me. It shut of like it was running out of gas and wont start back up. And now even if i try push starting it from the top of my hill the Tires lock up and it just shuts off.

Posted

Are you using the choke when trying to start it? sorry to ask a dumb question.

I will asked another one, is there any 2 stroke oil in the oil tank?

Posted

I will asked another one, is there any 2 stroke oil in the oil tank?

I will check. If there wasnt 2 stroke oil with that not let it start up?

Posted

yes there is 2 stroke oil in the oil tank, its not full but I dont think its empty enough for it to interfere with the performance. Sorry to keep asking but do any of you know if 40psi is the correct compression for this bike? I'm begining to think that the piston rod blew or something...


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