Hi, I was looking into the new Twin Air fuel filter. So far, I have only found this available on their site. It retails for $35 but they also want $13 for shipping. Searching on the-bay I find the filter material readily available for filtering down to different microns at inexpensive prices. These are mostly used to filter deisel fuel. I like the design of having the filter permenanently in the tank since it will also keep dust out as the fuel level goes down during riding. I emailed Split Stream who have a similar filter but not one specifically made for the 2010 and up YZ450F, nor do they have plans to make one. They do make them for the CRF, KX and RM. Perhaps that's because of the unique tank layout of the Yamaha or the fuel tank opening is a different size. I know this is the Yamaha forumn but could someone measure their fuel tank openings on CRF, KXF and RMZ's and post them? I suppose I can wait for the Twin Air filter to become more readily available from other sites as I won't be riding for a couple more months, or I could just buy one and move on.