The Oxford CMP crew have done a few in our time, 900x16's R/Fsplit rim, 1050x16's R/F split rim 1100x20's split rim, 900x20's bead lock, 750x20's bead lock, and 900x13's split rim and last but not least 600x16's split rim.... They were all total $$$%%stds.
Not one ever come off without loads of effort. I agree with Wayne if you can take the things to a tire (spelling noted Bob) shop spend a few quid and save a heart attack and hernia.
Pete
On a serious note never be tempted to put some air into the tube to try to split the rim, we've all been tempted at one time or another but it can really end in a short trip to the morgue
