Also, the lower end models didn't have a rear derailleur hanger and so the mech attached to the rear wheel dropout using a universal hanger like this
which clamps between the dropout and the wheel nut, or quick-release nut. In fact, for the most part these bikes came fitted with the ubiquitous Huret rear derailleur:
which might aid with identification. The frame was built with Raleigh's proprietary 18-23 tubing, which again might help you identify it one way or the other.
Also, the cheaper of the two models only has one set of water bottle mounts; the one with proper race spec has 2 sets. I think the latter also came with a fork with a sloping fork crown flush with the blades; the cheap version has a crown with a flatter top and a visible crown/blade junction.
Example pic of cheapo replica showing fork and rear derailleur mount here:
Another difference is that unlike this photo, the 531c model may well have had allen key brake bolts.
Link to pukka racing version here;
http://www.flickr.com/photos/27534652@N ... 735735@N24
There seems to be a subtle paint job difference in the seat lug area too. 531c version is yellow not black at that point.
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