12x28 sealed bearings for pneumatic wheels

Do you open and clean these bearings? I removed the metal shield with difficulty and found thick grease inside. Assuming these are not meant to be opened cleaned or serviced like pu wheel bearings. Meant for high speed applications? Just get new ones when not turning smoothly?

You don’t uploaded the photos, wait until 100%. I clean opening the bearing and use a Swab

The sealed bearings were designed to be maintenance free and a reason for the use of grease and not oil. They are not to be open once sealed.

I am assuming you are talking about these. These types have long service life. https://images-na.ssl-images-amazon.com/images/I/519gnEniVTL.AC_UL320_SR306,320.jpg

If it’s this type you can remove them and do whatever. https://images-na.ssl-images-amazon.com/images/I/41ns8G1yckL.SX385.jpg

Thank you. Makes sense. Now that I put them in a bones bottle with citrus cleaner I will probably have to keep adding bones cream or oil regularly. Washed out the grease and now they behave more like a serviceable oiled bearing. I removed a couple of the shields. Realized they were slightly bent when I put them back on. Carefully straightened them out and now working ok. Bottom line - don’t mess with the metal shield bearings!