I finally got to ride my long anticipated Passion 12 port stroker. First of all I took my 13 front sprocket off and went back to stock 14/41 gearing. For break-in I mixed up some yamalube at 24/1. After a few hot and cold runs I started to get on it alittle more and actually hit the powerband and WOW it hits hard and pulls like hell, the problem was the flat spot before the powerband. After pulling the plugs and seeing how black and wet they were I then leaned out the needle 1 clip and the midrange got better, opened up the air screws till they were 3 full turns out and it got even better, went down 1 size to 48 on the pilots and it got even better, the problem is I still have a bit of a flat spot at the midrange. I dont know if its because of the CPI pipes, the rich gas/oil mix or the main jet. My next trip out I will be done with this rich break-in mix and then I will check the main jet if I can find a safe place to get this thing to 6th gear WOT BTW...this was all done in wet, loose sand. If the main jet is not a problem then I'm gonna try going back to the 13 front sprocket but a 13/41 seems geared a bit low for a motor with this output even if I do weigh 275 lbs.