I have a 2000 DRZ400 with Keihin FCR carb. I Just completed installing a 440cc big bore kit, Ported cylinder head and stage 2 hotcams intake and exhaust. I also installed a FMF powerbomb headpipe and Q2 spark arrested silencer. I know that usu. when going to big bore you actually go leaner on jetting, but with porting you go richer. When I fired the bike it would only run for about 20 sec then die. It would seem to rum at part throttle but wont idle well at all (seems to run off of accelerator pump, then when it gets back onto the pilot it goes lean and stalls) As it is jetting is all stock. I have access to any jets I need, I guess what im looking for is input on a good starting point from someone who has tuned these things before.