It's an 18" frame Mike. I've still got my schwabble tyres, plus the kendra which came with the bike, so once the weather turns crap during winter, I'll be swapping them back.
Had a puncture as well today....while not even near the bike! Heard a hiss from outside the house, an the bak tyre was flat! Turns out, the rim tape doesn't cover one of the spoke holes, so where the inner tube was over it, it just burst!