Just get the mip clutch for the revo. Mine easily lasted me gallons and never slipped. I usually took it apart every half gallon or so and lightly sanded the bell and shoes, checked the bearings and just kept going. It never failed me, never gave me any problems. When it was time for a new set of shoes I remember I reused the spring off the old set and kept the new spring as a spare lol. Still never any problems lol.