I recently bought a YZ400. excellent bike very revy, great handling. Just spent £££ serviced it and bought motomaster disc/caliper. I took it to the dyno and it was a lil flat at the bottom of the rev range so the bloke said lift the needle up one to '5'. So I turned the carb side ways to get access to the top of it and removed the needle and moved it up one. Put it back together and now it wont start looking in the manual it shows a sping and a washer inbetween the locking nut and the circlip of the needle( i dont remember seeing them when I took it to bits) I pulled the spark plug out and it was all black so I used a lighter to take off the excess fuel and then put it back together, still nothing, it sounds like it wants to start but cant. So I put the needle back down to 4. Still wont start so I pulled the hot start and choke out and it worked?? as soon as you take the choke off it dies, it wont idle? Any ideas? I have the carb off atm and am in the process of cleaning it. The slide seems to get stuck slightly right at the bottom of the run. Is there an explodeable diagram with parts on for the carb with part numbers etc online??