I have an '05 Z400 with fcr 41ml carb,and I cant get rid of the bottom end bog.(I got a wiesco 12:5-1 comp,440,ported,stage 2 hot cams,drz valve springs,youshi full race,big gun cdi,lid off air box)Any time I crack the throtle it will die,or if Im lugg'n down on a hill and hit it, it doesnt crack open.Im running 180mj,45pj,5th clip.I have done some rescearch on ThumperTalk.com whitch got me more confused.They talk about adjusting my leek jet, and squirt duration on my acceleator pump.I was also told this is normal,THIS IS NOT ACCEPTABLE(to me)!!!

 

to me it sounds like your jetting is off. what does the spark plug look like after you run it a while? I run a 470 with a 180 main, a 180 seems to me to be to big for what you need, I ran a 165 main when I had my 440 , the 41 mil carb is a big carb for the 440, it will work you just hev to mess with the jetting on it

 

It seem'd to be running hot.I went down to a 175mj,38pj move'd the clip up to the fourth.It did'nt get any better it just made my head pipe glow.

 

I try not to mess with my carb, to many other thing to worry about , I bought my fcr 41 mil from sudco and they set my carb up for me before I even had the 440 done, when I did my 470kit I had the guy who did my 440 jet it, find a good shop that deals with perfomance and ask them what you might do,

 

Hey thanks,I like easy.Letting some one else mess with it sounds like a GREAT idea.Do you have the new'r hot cams with decompression release?I 'm having a problem with starting,and I am going to get the new'r decomp. exaust cam.Get that and this bog fix'd and she will be running great

 

Hey mucky, i seee that u know alot, i need ur help, lik i sai di just got my rossie on, and i rode it for awhiel, then i went outside after dark, and cranked it, the pipe was glowing, and i let a bud of mine ride it down the rode, and i see a blue spark or 2, come out the exhaust, is this b/c i havevnt got it jetted yet??...plz help?

 

check your jetting,and what have you done to the motor?