Lean jetting? Pipe glows fast.

Hi.

I just got a new bike. a yzf250 08. I just tried it down the road after changing oil. When idling I noticed the head pipe got really hot, all the way to the silencer. I rode it just to cool it offf but when I stopped the pipe was glowing all the way to the silencer after about 30 sec.. I stopped the bike and let it cool down. Then I checked the plug and the last mm of the electrodes was white and all black the rest. I only checked the main jet wich is 178, that may not be very useful for you, but I hope you can help. Do you think it`s my pilot circuit that is too lean or maybee something else? If it`s the pilot should I just try too go one size up or more? Or maybe just trying to screw the pilotscrew? Don`t know if it helps you but the temp is around 30 degreas f and the altitude is about 1500feet above sea level.

Thanks

#1 it should not be idled very long, one miniute fine,3 minites, scarry, until the pipe is red?? I am betting you had the choke on (technically it is an enrichener), this puts extra gas into the engine to help with the cold startup. Then needs to be turned off, the choke is putting so much extra fuel into the engine it is burning in the pipe.

Another option is the pilot jet is plugged, if so it will not idle properly

your riding in really cold temps so you need to go up 1 on the main jet...the header is always going to glow red its because of the valve overlap which is perfectly normal....the insulator around the center electrode on your spark plug should grey to light brown....that is when you know its jetted correctly....

#1 it should not be idled very long, one miniute fine,3 minites, scarry, until the pipe is red?? I am betting you had the choke on (technically it is an enrichener), this puts extra gas into the engine to help with the cold startup. Then needs to be turned off, the choke is putting so much extra fuel into the engine it is burning in the pipe.

Another option is the pilot jet is plugged, if so it will not idle properly

Well, It never idled for 3 mins. As I wrote the pipe glowed all the way to the silencer after just 30 secs when It idles after it`s warmed up.. I know it gets red but not like this. And the choke was not on. I don`t think pilot jet is plugged because it`s idling fine.

Reminds me of the old potstove in the morning, my parents would stuff it full of coal and really let'er rip! Glow a steady red in the morning.

I changed the pilot from a 45 to a 48 and the glowproblem seems to be gone. Will check the sparkpug tomorrow after adjusting the fuel screw.

The spark plug is kind of soot now. Didn`t have a screwdriver so I haven`t adjusted the fuel screw jet. It doesn`t run as good as it did now but I think that will be fixed when I get the fuelscrew adjusted.

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