1985 KX500 fuel coming out of intake!!

[sevenbridgesangler]

Hey all, I'm new here I just picked up a 1985 KX 500 this last Saturday. I knew it needed a few things when I bought it, it was a little beat up. I bought it mainly to try and restore it a bit. Well here is my dilema it rode pretty much perfect Saturday bogging after 3/4 throttle. I said no biggy possibly needs a plug fresh gas clean carb etc... Well sunday I went to go riding and it started and would barley run. I had to hold the throttle a little to keep it running. It would die at idle and die over 1/4 throttle. I brought it home (my buddy pointed out Saturday head gasket was leaking slighlty.) I changed the plug to an extra one the guy gave me. It did the same thing, so mi read on the computer to check the floats they were probably stuck. I cleaned everything the floats were not stuck. I put it back together and same thing. So i did it again and same problem. Then someone pointed it could be because of the head gasket it got worse from riding and starting blowing all the compression back uo through the intake. because it was shooting fuel out the carb into the air box. any ideas what is happening???

Sorry for the long post just trying to give as much detail as I can.

[Purpletj]

two issues I see. Set the float height and also, I would recommend a new set of reeds. A good set will make a world of difference over the worn out ones.

[Goat]

Check to make sure the rubber boot that bolts the reeds on and carb slides into isn't leaking air from dry rot cracks. Very common on the older bikes. If there are cracks you can silicone them or buy a new boot. Silicone is much cheaper but doesn't look the greatest. Check your coolant if it's dark (or smells like premix) it may also be the head gasket. If I think of any other possibilities I'll get back with ya. Hope this helps.

[sevenbridgesangler]

How do I set the float height? I'll look into a new set of reeds soon. I just dropped the carb off yesterday at the local race shop to let them go over it. I should have it back today. I also ordered a head gasket for it I should have that today or tomorrow. Also with the reeds if they are worn how can I tell? cdan I just replace reeds or is there more to it? I don't know anything about 2-stroke gas engines. I'm a diesel guy 

I'll take a look at that boot when I get home from work today. Thanks guys.

[Friar-Tuck]

http://www.allthingsmoto.com/forums/f-15/how-set-your-motorcycle-carburetor-float-level-13609/

http://justkdx.dirtrider.net/floatlevel.html

 

[sevenbridgesangler]

Well I got my carb back yesterday. He told me that it looks like whoever owned it before me took pliers to the needle jet He did replace it for me. (even though it's a new needle could it still need adjustment? I imagine when they put it in they probably adjusted it not sure though.) I put it back on the bike and started it. It ran better but it still leaked fuel out of the intake!! The head gasket should be in today so hopefully thats the last piece to this nightmare puzzle.

[Friar-Tuck]

Diesel Guy Meet Two stroke engine guy
http://www.kxriders.com/coppermine/displayimage.php?album=search&cat=0&pos=0

  The first few pages give you a great primer on what does what in the world of two-stroke 
     Tuck\o/

[sevenbridgesangler]

Well I replaced my head gasket and it still runs like s**t didnt check if fuel was coming out of the intake but was still smoking pretty heavily and not running right. any ideas?

[Goat]

Still could be multiple things causing it to run like crap. Best to start with the cheapest and easiest things first as I'm sure you know from working on diesels. Carb adjustment and jets would be the first thing.

Link for carb tuning and jetting chart - http://www.kxriders.com/forums/index.php?cat=9

If the reeds have seen better days... When you pull the reed cage out there should be no gap between the reed petals and the cage. If there is any gap you can try flipping the reeds over but usually that doesn't help. I do know you can get a set of Boyesen reeds off ebay for around $40 shipped.

Hows the air filter? New, slightly old or 25 years old? lol 

Might want to pull the flywheel and check the keyway and key to make sure it's not throwing timing off. Check the stator coil and make sure its not rusty as that will make it run like crap and eventually not run at all. If there is any rust you can use some fine grit sandpaper to clean it up. Also if there is any sludge in there the crank seals may be bad. Which would cause it to not have the vacuum it needs to pull the fuel up to the top of the piston to burn.

I'll keep thinking but I hope this helps.

[sevenbridgesangler]

Alright thanks for the help I'll start checking stuff this week. I'm way to lazy to go out and do anything right now

[fluffy]

float level has caused me plenty of problems. i go there first. i havent seen to many bike still run with major problems.