2007 yamaha yfz 450 wont hold idle

[Drmundy]

got a 2007 yamaha yfz 450 that wont hold a idle runs awesome when on the gas but as soon as i let off it dies. mods i got done on it are full trinity racing pipe, dyna rev box, k&n air filter. running a 190 main jet rest of the carb is stock. set my idle screw all the way in and all the way out and everywhere inbetween and get the same result. was told there could be a vacume leak, anyone else run into a problem like this?? also has anyone herd of any EFI conversion kits available?

Edited April 5, 2011 by Drmundy
lack of information

[MIKEL5469]

first thing i would do is check eith the pipe manufactuer to see if the carb is jetted big enough

[predrider305]

Believe me when i tell you I AM NO EXPERT, but it could be the pilot jet. That is relevant up to 1/4 throttle. Just a guess!

[DirtDemon]

Your thinking isn't off base there Predrider, I was thinking that a pilot screw adjustment might help, or you may need to adjust your valves. Is it ever hard to start? I don't know of any EFI kits are out there, but if there are, I would bet they are extremely spendy.