http://www.ebay.com.au/itm/YAMAHA-350-BANSHEE-BIG-BORE-ATHENA-392CC-PISTON-CYLINDER-KIT-1987-2012-/321215845216?pt=Motors_ATV_Parts_Accessories&hash=item4ac9f4d360&_uhb=1
new with pistons
Pro circuit's = lowend power
CPI's = top end power...
what do u want from your bike.
i have CPI's ... great mid to top end, but shit bottem end
suted to drag and on BAND riding