Paraffin is my choice. Effective and cheap. I use it with a grunge brush and it's easy enough to let the crud settle out (in a suitable container used to dip the brush while cleaning) and to decant moderately clear paraffin if you feel like being really parsimonious.

I have one and have used it on 4 different bikes including heavy ones like my BMW GSA and Ducati Multistrada 1260. It works very well and is great for getting access to the under parts of the bike. On a smooth floor, you can move the supported bike around easily. The floor does need to be smooth to ...