Cant start yzf 400

i am suddenly having a hard time starting my 99yzf400. real hard to start with choke in or out when it does finally start and i put the choke in it stalls.

i put in the hot cams with the decomp mod about6 months ago but the problem just started now. checked the valves and timing all ok. current jetting is 185 main 45 pilot the rest stock on carb. only other mod is an fmf full exhaust.

any ideas? id like to get at least one more year out of this bike

Running the same fuel as usual? Has it gotten colder in your area lately? I am not sure about the 400, but the 185 sounds rich to me but that would help with starting and kill the motor once it warmed up if the choke was left on. Is your carb spotless? It could be a clogged pilot jet. I doubt your bike is on its last leg just yet.

well, i looked thru the carb real good and gave it a good cleaning backed the main down to a 180 and still no luck and then thru trial and error i noticed someone had turned down my idle screw to about zero. after some pretty heavy interrogation i got a confession from a friend of my 6 year old son.

thanks for your help.

Did you whoop him? :banghead:

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