Quote Originally Posted by Jonathan View Post
Hmm, I even looked there... must be blind:

http://www.arceurotrade.co.uk/Catalo...-Ball-Bearings
Or...

http://simplybearings.co.uk/shop/p42...duct_info.html

or...

http://www.ebay.co.uk/itm/E8-MAGNETO...item2eaeaac383

etc.....etc...

Aluminium disk or whatever with only a very very small clearence - enough to stop it touching, but not so big that it lets lots of dust in. I believe the term is aluminium labyrinth. Any seal which touches is going to generate a lot of heat due to friction.
Was going to see if I could reverse engineer a shield like on the 608RS bearings....or how about http://simplybearings.co.uk/shop/p24...duct_info.html but not sure what speed it's rated to....food for thought anyway!