I would run some diesel fuel in it. That will give it a little lubricity but also act as a solvent to break down the oil. But I wouldnt run it long with that stuff in it while riding it. I'd probably just jack it up off the floor and just fill it up with diesel and rotate the front end to slosh it around and empty and repeat that a bunch till the diesel coming out is clean. I dont think it would hurt the clutch disks inside?
2005 Brute Force 750, Big Gun full exhaust, ITP SS108 12" Rims, 27" Mudlites, K&N
Pro Armor Skids, Custom Advanced Timing,
3000lb winch on recievers front and rear, Rejetted
Over 322hrs of hard life and counting!