I bought my 2008 yamaha warrior xv1700pc around 2 months ago and when I bought it I noticed that it had the modification to the ecu for bumping it to a higher air fuel mixture amount. I began to research as this mod seemed to good to be true.... everything I have found online says that the bump only affects idle or just off idle... even the yamaha manufacturers say so. I purchased my power commander 5 shortly after because I thought I'd better have it so I can tune it for the mods I had planned. Currently I run vance and hines big radius pipes with stock loud baffles and cones filters straight to the throttle body... I messed with the ecu bump slightly but I didnt think it was worth my time because of all the negative it surrounding it... about 2 weeks ago I found a small thread mentioning churchkey and him saying that if you bump up the ecu 35 points per cylinder and then check your plugs you will see that it does in fact affect the entire map at all rpms... finding this thread I set my power commander to all zeros and reset my throttle position sensor to what it was before I installed it.. after 1 week I removed the power commander and this is week 2 or 1 week without the power commander at all and the bike runs really well so long as I set the ecu bump correctly and resync my throttle bodies. When I bought the bike my ecu was set to CO1=4 and CO2=2...but now that I have mods installed and such I have CO1=20 and CO2=17 and I resynced the throttle bodies and this puppy runs like a raped ape... I apologise of others have already found this conclusion but I couldn't find enough info about it so decided to post about it... the ECU bump is way way more than a bump and I am going to continue to mess with it as my cylinder cut off seems to have been gone away with as well now... any questions from others I will answer to the best of my knowledge but I credit Churchkey for the original thread and wherever the person he told got the info from him at..thanks guys and thanks churchkey! My fellow warrior lovers I hope this helps with something as it helped me get rid of my power commander and my bike is like new again with whatever mods I want.