400ex will not start after pipe install

[apalusso]

I have a 01 400ex with no mods, no holes in air box, all stock. Last week I installed a WB e-series slip-on and after that my bike has been going though spark plugs. I rejetted the bike, and the plug was black so I went back to the stock jet. Now the bike just seems to go through spark plugs. I was wondering on the WB there were 12 rings and I placed all 12 on, should I lessen the amount of rings... no clue what to do. I could use your help... right now the stock jet is back in and will not turn over. Oh, the battery is new as well and charged correctly.

[EXDUNER127]

what size jet did you go to when you installed pipe?
you seem to be running rich. how many sizes did you go up?

[44oEX]

IF you didn't change the filter you probebly don't have to rejet.
So keep your stock. But you could go with a 42 pilot jet.

Keep the 12 disk that is how it runs best.

If it doesn't turn over it has nothing to do whith the pipe.
Maybe you need a new cylinoid or you have a bad ground in the wiring.

[EXDUNER127]

is it just not turning over, or does it not start at all, like no sound when key is turned?

[apalusso]

I went up one size on the jet... I placed a new spark plug in it and it started just fine. But now when I rev the bik it back fires a bit now. Would the wrong size jet make the bike back fire? The bike tends to lag... and the spark plug is a bit black not a brownish color. What should I do?

[apalusso]

With the WB e-series exhaust... it came with a new air filter and I did but that on... should I get another one or put back on the stock filter it is new as well????

[cals400ex]

either filter will be fine.

what jetting are you running??? i want to know your main, needle location, pilot, and fuel skrew location.

[apalusso]

My main jet is 155... I have not changed the needle position or anything else. Basically all I did was go one size up from the stock size main jet. Placed the new air filter on, slapped on the slip-on exhaust... placed a new spark plug on (I checked the color has some black in it) and that is it. Nothing else. Everything else on the bike is stock. No engine mods or touching anything on the carb. I am not the most mechanically knowledgable but in my last post about changing the slip-on that is all they said I should do... place a 155 main jet and place on the new air filter and my bike should be ready to go. Oh yeah there is a new battery as well that is charged at the correct voltage. Thank you for your help.