realise this is a really old post, but did you ever get to the bottom of this? I’m looking at a Raleigh Royal frame on eBay, which has been repainted, and it has a similarly mysterious serial number, and I’m unsure if it’s legit or not! Serial is C18036Resurrecting an old thread here...
I've recently acquired a Raleigh Royal. Based on the spec and frame colour I'm pretty sure it's a 1989 model. FWIW, the bike is black with a silver head tube and fitted with an Exage Biopace triple at the front. The rear wheel and cassette is not original so no point listing that.
Anyway, I thought I understood the Raleigh S/N convention but not with this bike as the no. is B25023. Can anybody enlighten me on how to interpret those numbers please.