I am working on my friends 400, trying to fix the popping on decell...(a lean condition) so I pulled the carb off, inspected and cleaned everything. I found that it had a 170 main jet so I installed a 175 (per yamaha manual) and lowered the needle clip one position and installed a Zip-Ty fuel adjusting screw 1-1/2 turns out. It has a White Brothers E-series muffler 12 disc's also. I put it all together and tried to start it and fuel was coming out the overflow tube, I figured the float was stuck so I pulled it all apart and checked it out, didn't seem to be sticking but anyway I messed with the float level for a while and it was still pouring gas out! I then readjusted it to the stock level (9mm) and put it together and it stopped pouring gas out! So I then tried to start it...I did get it to start but I can not seem to get the idle set? It will start and seems to run fine with the choke pulled but as soon as I push the choke in it dies, every time. How can I get the fuel screw adjusted properly if it won't idle without the choke pulled? If I bump up the idle it doesn't help, it then won't start unless I turn the idle down again. Does the throttle cables have a lot to do with this problem? I adjusted them also and it didn't seem to help either!? I am pretty sure the slide was installed correctly (I was watching that carefully) Any suggestions?????????????????