I'm in the market for my next 4 wheeler and I was pretty sold on a raptor 700, but I'm slowly leaning towards an 07 or 08 yfz now. (I can never make up my mind) I have been running regular 87 in my stock 400ex for years with zero issues. My buddies 05 yfz has a sticker on the tank that says never run below 91 octane. Is there a reason they say this, or is it just to ensure maximum performance? This is 100% a deal breaker if i can't run regular cheap 87 octane on stock compression.