Oil usage & engine lock up

04 KX250F,can't have more than 30 hours, been using oil and running hot since day one. Engine seized up today after stalling during warm up. Kicked over normally several times to restart then locked up. Haven't torn it down yet so I'm not sure what exactly broke/seized. Anyone have any thoughts or seen/had similar problem?

After reading more posts, I'm wondering if I have a broken valve sitting in my bore. Put in in gear and rocked it a bit, engine rolled over slightly. It was completely locked. Actuate kick start by hand and the engine locks up again. I'm suspecting it's locking up as it approaches TDC due to a valve resting on the piston?

my buddy had the same thing happen it was the lower end went.also the cam chain was bad also.could have a blown main seal and sucked dirt

There's no point in guessing what happened, pull the head off and look :cry:. You say the engine seized, it doesn't just seize and then run fine.

All four strokes use oil. They will use a little EVERY time you start them up. If you do add a little oil between oil changes (sometimes .1 quarts between 3 ride oil change intervals) then you will run out of oil and lock up the enigne. Does anyone maintain bikes anymore, or just run them til they blow up and call them junk?

u know isaac, i'm starting to suspect we had a lot of newbies buy bikes and now are trashing them because they don't know what they're doing. I have nothing against newbies but don't diss the bikes if you don't know what you're doing. It's okay to have questions but don't blame the bike for your own lack of knowledge.

u know isaac, i'm starting to suspect we had a lot of newbies buy bikes and now are trashing them because they don't know what they're doing. I have nothing against newbies but don't diss the bikes if you don't know what you're doing. It's okay to have questions but don't blame the bike for your own lack of knowledge.

When these bikes are ridden hard they ALL use some oil, 300-400 cc per hour is pretty common when they are pushed hard. I don't know if that is duckman's problem here, but the fact remains that single compression ring pistons USE OIL PERIOD. Some use more than others but they ALL use oil. It's a direct consequence of that type of piston design decision. All the CRFs have similar style pistons and they all use oil as well.

There's no point in guessing what happened, pull the head off and look :cry:. You say the engine seized, it doesn't just seize and then "unseize" had it seized it would have stayed stuck.

Correct me if im wrong, but a engine may sieze up, and then once it cools and the metal contracts, it can possibly unsieze. Happened to me on my kx125 once.

I guess I'm shocking the world.

my buddy had the same thing happen it was the lower end went.also the cam chain was bad also.could have a blown main seal and sucked dirt

This ain't a 2 stroke scuba. 4 strokes don't suck dirt at main seals. :cry:

I really agree with the comment found at the bottom of 4strokerule's post. The one below the dashed lines. It is the truth. dirtmachine should be in stand up. I'd pay to see one of his shows. I can't imagine an hour of those kind of comments! :cry: :cry:

So did you take the bike apart yet? Have you found out why the thing locked up yet? Or did you throw in the towel and take it back to where you bought it? That's what I'm going to tell you to do. Just take it to someone who knows what they are doing. Yes it will cost more, but with the mechanical knowledge you have shown: I'd take it to somone who knows what they are doing. :cry:

so there is no main seals at the bottom of the motor??????? so what keeps the dirt out of the seal then??????? my buddy's that i mention it would run for 5 mins then shut down.let it cool off and it would run.it was the crank that was bad and the cam chain.

Yes it has main seals, that's what holds the dirt out. But it won't suck the dirt in when it goes, it will blow oil out. :cry:

No, I haven't pulled it apart yet. I'm not one to throw in the towel either. I might be a newbie to this forum, but an idiot I'm not. I've been around awhile. I can ride, and I can turn wrenches. In fact, I've been making a living turning wrenches for about 30 years. At my age, I thought this bike could handle a bit more than I could dish out. I'll keep riding my YZ and get into the KX this winter.

I don't blame the bike, and it wasn't because it isn't maintained. I came here looking for input from other riders who may have had similar experiences with this new bike. Not comments from finger pointers who know nothing about me. Thanks to those who post helpful info.

No, I haven't pulled it apart yet. I'm not one to throw in the towel either. I might be a newbie to this forum, but an idiot I'm not. I've been around awhile. I can ride, and I can turn wrenches. In fact, I've been making a living turning wrenches for about 30 years.

Duckman - This is one of the easiest of the new crop of engines to work on so don't sweat it. Grab your wrenches and have at it.

Yes, if you feel you can find out what's going on do it. Take it all apart by yourself. Then when you find out the problem post your question. This forum is nothing but comments like this: "my kicker won't move, it feels jammed, does anyone know why it won't move?" or "I just got my bike and it won't run anymore. What broke?" All you people that are complaining about something being wrong, but not tring to take anything apart and fix it. Anyway you look at it you are going to take half the motor apart to fix most things. So just tear it apart and get to it. If you have been turning wrenches for 30 years, then you should know before you fix anything you have to know what broke first. I have been turning wrenches for 5 years now and I know how that works. And before you can find out what broke and why it broke you have to know how it works when it isn't broke. ANY person that has been turning wrenches for 30 years should know this.

All four strokes use oil. They will use a little EVERY time you start them up. If you do add a little oil between oil changes (sometimes .1 quarts between 3 ride oil change intervals) then you will run out of oil and lock up the enigne. Does anyone maintain bikes anymore, or just run them til they blow up and call them junk?

When did he say it ran out of oil? Never, He says it is useing oil. How can you say he is not maintaining the bike from his post? Because yours hasn't broken YET?

He never said it was junk. He also didn't say it fired over after it seized. He said he could roll the engine over by hand after he rolled the bike in gear a little. Then when it hit tdc it jammed. It sounds to me like he was just trying to see what to expect when he did tear it apart, but instead you tear into him because you can't except the fact that our bike is not perfect. You made us all look like jerks.

I would strongly recommend getting the service manual before you start pulling the engine apart.

TBJH-hey it's great to see you put in some input. Since I'm sure your 2 other posts have contributed so much. By the way he also said he has been turning wrenches for 30 years. So if he is such a good mechanic I think he should use his knowledge and fix his bike. Then after it's all fixed up and running report his findings and fixes. That would be a big help to other people. A lot bigger help then just saying "Oh my bike broke, what's wrong with it?" And when you don't give us too much information to go off of, how are we to help give info. back? You are right that he didn't say he ran out of oil, but he also didn't say he added any. So what are we all supposed to believe? Especially since half the people in here THINK they can fix anything, and can't. So before you make another off the wall comment yourself, sit back and read ALL of the posts in the site and see what kind of crap you hear every day. :cry: :cry: :cry:

TBJH-hey it's great to see you put in some input. Since I'm sure your 2 other posts have contributed so much. By the way he also said he has been turning wrenches for 30 years. So if he is such a good mechanic I think he should use his knowledge and fix his bike. Then after it's all fixed up and running report his findings and fixes. That would be a big help to other people. A lot bigger help then just saying "Oh my bike broke, what's wrong with it?" And when you don't give us too much information to go off of, how are we to help give info. back? You are right that he didn't say he ran out of oil, but he also didn't say he added any. So what are we all supposed to believe? Especially since half the people in here THINK they can fix anything, and can't. So before you make another off the wall comment yourself, sit back and read ALL of the posts in the site and see what kind of crap you hear every day. :cry: :cry: :cry:

Contributions? I spent the last few hours wandering around this forum, where are your great contributions? Are they the ones where you pick on people that can't spell, type, or misplace a part? You ask a lot of questions, rant on about others, but I haven't found your significant contributions. "So if he is such a good mechanic", where did that come from? Did I claim to be the greatest thing to ever be turned loose on the wrench turning world? No. "Oh my bike broke, what's wrong with it?", I read my original post twice, I don't see where you come up with this quote. How far up your ass do you reach to find this stuff, and how to you get your hand in there with your head in the way? Again, I might be newbie to this forum, but I'm not an idiot. Proof? It didn't take me long to figure out that your a dick.

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