Have a 2003 ksf-80 qaud has good spark and its getting fuel but it will not start. the plug seems to be wet from fuel each time i check it, this problem started after one day the kids road it and the next day wouldnt start

If you've verified you have good spark on the plugs while turning over the engine with starter.... And if the plugs are wet with fuel after attempting to start the bike, then it is very likely that the timing is badly off. Checking the timing to specs. In the manual.

wrong fuel mixture , or wrong ignition timing ,check for vacuum leaks at the manifold and carburetor , check valve and ignition timing and spark plug cables. also check the fuel pressure and flow.

The plug gets wet and the unit has good spark? That only leaves you with two things....fuel and compression.
Dump it just be safe and mix up a batch of totally fresh fuel! You might even put a small amount of system cleaner into it to chase of water and remove gums and varnish too. Hey...if the rings are stuck it might even free them up! Kudos on checking the head bolts....they do often get loose and drop compression enough to prevent starting. Now that you have the head bolts ruled out check compression with a guage and see if you have 80-90 psi compression. Be safe and good luck!

If fuel smell from exhaust then most likely not firing. Check for a good spark, also check spark plugs. They are probably wet with fuel. Clean and dry them or replace with good ones and try again. If plugs always getting wet but spark to the plugs is good, look for cause of flooding. Maybe leaky needle and seat in carby, blocked air intake, choke stuck on etc.

wow no year , impossible to help really , save generics.
what engine, name it, what country, some countries have other engines and other EFI controls.?
is spark good to ALL cylinders ,not just one?
if yes, are spark plugs relics or fresh, and are they dry or soaking wet (tips) with fuel>?
getting fuel means zero if where is not said, spark tips?
it only takes 3 things. to start. most skip compression , id never do.
but yes, a bad engine WILL not start.
150PSI on all cylinder W.O.T , not 80, if
good spark on all cyl. and timed to spec, "timing light time)
last is fuel ,never 1st or second.
last , is sparks are wet its flooding, (lots of tests ask)
last if spark tips are dry , then introduce test fuel
run of 3 second and stall now, (ask for how to preceed.)
all this is called BASICS. we can peel the onion as deep as you want
ask.

Not much info to go by, but i'll give some things to check. Got fuel? Got Spark? Got Compression? If you have all these things, after kicking several times, pull plug to see if the plug is wet. If wet dry with compressed air, ground plug on head bolt or use spark tester, Kick engine over while watching plug, it should spark. If not replace and try again. If still no spark, check kill switch with ohm meter to make sure is working properly. If still no spark you will have an electrical issue with either the CDI Box or Stator. If the plug was dry without fuel, pull fuel line from carb. check to make sure fuel is running, if not check fuel shut off valve. sometimes the shutoff valve will clog up. If all is well it has to be a clogged carb.. Good Luck

Get a compression test done.

Gotta start with the simple things...
How do you know the compression is fine? Since you did not give a compression reading I do not know what method you used to test the compression.
How do you know the fuel system is fine? The plug is wet with what? Could it be water?
How do you know the spark is fine? Have you used a spark tester? Or did yuo use the spark plug on the side of the head? Did you know a bad spark plug can still spark under regular condition but wont spark under compression?

You left out valve timing- its a 4-stroke.
First put in a new plug. Then see if it hits on a prime ( see my tip on diagnosing a small engine).
If you have double checked all the basics and are sure we have fuel,compression, and ignition and it still wont start then check your flywheel key and valve timing.

Need to have Fuel and Sparks to fire up an engine. Let's check it out..
1- Start several times.
2- Take off one spark plug.
3- If it is wet, there is fuel.
4- If it is dry, no fuel. Fix this problem
5- While spark plug is out, touch it to the engin chasis and have a helper to start the ening so you can see if there is spark strong enough.
6- If there is no spark, Fix this problem.
7- If there fuel and spark then check out cold start valve, it is bad causing flood so it could not ignite.

It seems tht it also doesn't start wth the choke in 'off' position.
Two things:- (1) :-check if the spark plug is wet wth fuel.(Crank it for a little cranks and thn remove the spark plug to check if its wet.)
(2) :- check if you do get sparks at the spark plug, by grounding it to the engine away from any fuel fumes!
I am sure one of the two is missing thts why its not starting.
Let me know the out come please.