Thanks for the reply. As I suspected then, there are plenty of 21" examples around at great prices, I cannot find any photos of a 21" frame built up though! I don't really want to end up with a gate...
Nice builds by the way, shame about the packing of the ti version.
No worries, I should imagine the 21" being huge, from centre of bb to top of st I reckon 22" and extremely long at nigh on 25".
For me they cocked the sizing up of these frames because there needed to be something in between the 17" and 19".. I have a 17" flyer cromo and it is 17.5" centre to top.
You can find the geometry here: http://www.saracen.co.uk/bikes/2012/trail/kili-flyer-ti