Jump to content

07 250 cutting out


Recommended Posts

hey guys, have an 07 yz 250 thats cutting out under throttle. New plug, checked and removed cap etc etc. It did this once before a couple months after i got it but i forgot what fixed it.

 

Here's what it'll do: Ran great last weekend, this weekend is when it happened.

 

Starts, revs , idles as it always had. Get a load on it on the track, accelerates then you can feel it start to cut out but continues to pull, it'll hit the top end and it'll cut out bad, release the throttle and hold at 3/4 and it'll bog till you slow down then picks back up. Pulls strong till it starts doing all this 

 

I changed NOTHING, same oil ratio etc. Acts like a carb, but gut tells me spark, because you can tell it's leaking a lil oil out where the pipe connects to the head. Pulled pipe, checked piston and it looked good secondaries are closed when not running . Old plug was the usual tan. Pulled flywheel cover nothing looked out of the ordinary.

 

Think reeds would do this?

Link to comment
Share on other sites

I am leaning toward a carb issue or more like a fuel thing.  Start at the source, blow back though the fuel line, back into the tank to make sure the fuel line is clear.  I would take the carb off and take off the bowl.  Sounds like something kinda plugged in there, or about to be.  While you have the carb off, take a look at the reeds, make sure no breaks, chips splits and make sure they close well.

 

Try this first, if this isn't it, we move on to something else.  Document everything to be safe.  Easier than guessing what you did.  More important as you get older, trust me.

Link to comment
Share on other sites

by alternator, do you mean the stator? How would i check those two? Plenty of compresssion, have to start it with a boot on. Ran perfect the week before. i rode it throught the day like this so if there was water its been burned lol

Don't assume this! Water in the bottom of the carb will sit there for an almost indefinite amount of time! It's just much smarter to pull the float bowl off and check for water than to assume it's been burned off.

Link to comment
Share on other sites

im gonna pop the sub frame off, pull the bowl and check reeds. Then move onto the other stuff, water would make it boggy everywhere though, it is just as powerful on the low end as its always been

Not necessarily,  Water if going to go to the lowest point which would be the drain screw and it would only but a problem at wot when your pulling fuel from the main jet.

  • Like 1
Link to comment
Share on other sites

im gonna pop the sub frame off, pull the bowl and check reeds. Then move onto the other stuff, water would make it boggy everywhere though, it is just as powerful on the low end as its always been

if it was in your crankcase it would be noticeable everywhere. Go get some avgas and throw it in there, run it for awhile, when it cools down the avgas will dissipate the water. Water will not leave of its own free will if it is inside the engine.
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

×
×
  • Create New...