Found the info by calling someone that was selling a kit online. The bearings are 30mm inside diametre, 55mm outside diametre. Height doesn't matter that much, but it seems the standard height for those ID and OD measurements is 17mm. Both the top and bottom bearings are the same and they are the same on the Wee and Vee. I got some Koyo bearings off eBay for £23 for a pair. There are cheaper bearings, but I trust Koyo bearings and I don't want to need to ever think about the steering bearings again after replacing them this time (once is enough
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