A mesh type filter would help cut down on dirt and dust from the outside air,but the belt itself when it wears down makes the most dust that sticks to the clutches,along with the ramp button and guide button wear.Just best to clean em out once a year or so.

 

Hmmmmnnnnn, thought the '12 Polaris 400 had EBS, running that '77 belt was for a ton of applications on older 400 Scramblers from like '95-'02, and old Sportsman 2 strokers

 

The 2012 model 400 used the non ebs clutch system.

 

My dads 97 500 has no EBS yet he takes the same belt as me. 3211069
I just thought the one way bearing in the drive clutch was the only difference between EBS or not.

 

The first belt used in the 97 500 was #3221048 then it changed to the 3211077. #3211069 was used on the 2000 500 ebs. They had both clutches available that year and some even ran the ebs belt on the non ebs systems with no problems. Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse