Cant figure out

[overbore]

Have tore carb completely apart,and changed needle
position twice down both times,tried different pilot jet,
pulled reed cage and examined with it being ok.Still can
not figure out why the engine just runs on when coming
down to idle.Have tried changing timing with no change
that I could tell,different plug,different gas,and it still does
it.Have tried propane torch with just propane around flywheel
and couldnt hear anything differnt.Is it a air leak or could
it be a exhaust valve,head gasket,crank seal,ect?
please help or give suggestions or test that you would try.
overbore

 

[RM_guy]

I have to ask the obvious. Is the slide returning all the way when you let off the throttle? The exact same thing happened to my sons bike yesterday. I had the tank off and had inadvertently nudged the throttle cable out of place. It was just enough to give it a fast idle. When you release the throttle you should hear the slide bottom out in the carb before the throttle tube does.

 

[overbore]

thats ok I would have asked also.Its fine and the carb has been gone over
with a fine tooth comb.

 

[Nevada Sixx]

are you using a reed spacer? that may make a bike run on and on.
maybe try a colder spark plug and check your head gasket for leaks.
maybe try turning in your air screw (not idle screw) to cut some of the air out. let us know if you find out why bike wont die.

 

[overbore]

already had tried the air screw with no success,and there is no spacer as
I had the reeds out and it just had the boot that hooked the carb with the
flanged fitting on the other end.It will die,
I am just talking about it taking 10 extra secounds to come back to idle right
after running it hard or at least half throttle.will keep trying stuff and any
other Ideas are appreciated as this one is eating my cake.
overbore

 

[overbore]

replaced mag side seal today with same results of engine
running on when it gets hot and the motor does seem to get
hot especially if its just sitting and idling with the occasional
blip of the trottle.Have other seal for the wet side already,but sure
would like someone else that has fought this problem.
any and all ideals are welcome.will check water pump out tommorow
and may tackle other seal.I just wish I knew for sure without just
replacing parts.