125 Mystery Problem

[caleb99]

my 2003 kx 125 worked great for 3 months no ishues with anything. one day at the track i was comeing into a corner pulled in my clutch and the bike died after about 100 kicks we desided to load up the bike and investigate this is what we have done
-new plug with great spark
-new air filter
-flawless carb
-no sheared key and no spun flywheel
-has new piston with no hole only 5-6 hours on it.
-new reeds
-timeing is right with Top Dead Center of piston and spark
-cylinder looks great
so after all this investigation me and my Father (both very knowledge in the dirtbike world) are stumped it is getting gas to the engine and air and it has compression.

The bike wouldnt even start with starting fluid and every now and then (not very often) their will be a back fire.
when we pulled the head off to check if the spark was timed right it actually had ignited the starting fluid that we had sparyed in their earlier…so basically its either the bike just has an attitude problem and doesnt like me or the gods just dont want the bike to start…..sooo if you have any idea what could be wrong please anything will help.

 

[jaguar]

there can be spark when the spark plug is outside of the engine but not when inside the engine. that is because compression makes it harder for spark to occur.

 

[jaguar]

you could of blown a head gasket. You need to check compression with a gauge.
firing at TDC is not right for idle timing. should be around 10 degrees BTDC.