Same bike, same problem. I have a 400 main (2 sizes leaner), stock everything else (you may want to go leaner on the needle clip by going to the second clip). I have a PC pipe and silencer. Honda HP-2 at 32:1 was too rich for me, so you could try 40:1 (what the local honda shop recommended) or try amsoil or motul. I would take amsoil 10 times out of 10, but motul is good, too. run it 50:1 (trust me, I thought the same thing too, but it is good). Also i have to run the 8 plugs, i have not fouled mine in 9 months, but you can stick a new 9 in and i will foul it before you can sneeze. I ride woods alot, so every now and then when riding I have to ring it out. Try WD-40 to take the spooge from your bike. I have some out the silencer all the time. Hope this helps, i live in humid tennessee at about 1000 ft. elevation (close to Loretta Lynn's).