i picked up a 02' bayou 220. in doing some routine maintenance i noticed a problem. i was going to change the oil in the rear end and removed the filler plug and found that the entire rear end is filled with grease! looks like wheel bearing grease that someone just packed in there. the bike runs but due to the bad tires i have not rode it. now i am trying to figure out what to do? i can take the whole rear end apart and clean and inspect everything or or is there a way i can add like a solvent and spin the rear tires to loosen up the grease and drain it out and repeat as necessary to remove most of the grease and add oil. i will for sure keep an eye on it and have to change the oil a couple times to get most of the grease out? the bike had some missing pieces and a few problems when i bought it but for $200 i cant complain! thanks!

 

Some people that mud alot fill their diffs with grease to help prevent water entry or its just really old and has mud and junk in it. Should be alright to just flush it a few times

 

I wouldn't put a solvent to wash out the grease...
Just run correct oil, use it lightly and drain. Do that a few times.