QUOTE (machzguy @ Nov 15 2009, 09:35 AM)

And i did have the prefilters when i sent them back to timbersled they examined them and said they do not understand why they did not work.
Did you preoil the filter element?
Timbersled filters use the same element as K&N and in a non dusty enviroment you donot have to oil. But in the case of the RT belt dust issue you do need to preoil the element just like any K&N filter element. Preoil the filter with K&N element filter oil, then slip the socks on and your good to go. It is important to use the socks though, especialy in a moist enviroment. The socks will protect the filters from water and dust.
I use K&N filters on all my toys with awsome performance and engine protection. F-350 powerstroke, Polaris sportsman quad, Northwest jetboat with a 5.7L, Ski-Doo RT1k......all K&N style filters. Preoil, socks and install, good to go.
If you operate in an EXTREME like mud and real heavy dust then i recommend the UNI foam filters that you oil up. HOLY if you do that with your sled.
Plus they filter poorly without the oil and are MESSY. my2cents