found the bearing i was after and despite needing two i only ordered one (will make a point of reading the blurb rather than looking at pictures before pressing “buy”). it’s a ceramic bearing (6805 2rs), rolls smoothly, but has about 0,5mm play side to side. is this tolerable? guessing that upon fitting and tightening the hub up play is taken care of and everything should be dandy…. right?

tell me it is so before ordering the second….

cheers.

Typical cart bearings for bicycle applications are designed for radial loads only, but with allowance to take some angular misalignment, hence the movement you feel. This means it is a well designed and well constructed bearing. If there was no angular play then they would wear out very fast indeed. If there is no radial movement there is no problem. The bearings sound fine.

Google bearing misalignment this was first hit.
Or look in Shigley who has a couple of pages on this.
http://www.rbcbearings.com/ballbearings/misalignment.htm
http://www.astbearings.com/ball-bearings-radial-play.html

(copied from my previous answer in this thread http://singletrackworld.com/forum/topic/replacement-cartridge-bearings-ordered-for-hub-but-seem-to-have-play-in-them#post-6779897)

thank you, toys