ridley sizing

xixang

I'm looking at buying a ridley helium but a bit stuck on sizing. Currently riding a medium giant tcr (which is a little stretched I'd guess from back ache I get on longer rides) which I think is about a small ridley but I'm finding conflicting info on frame sizes/geometry. I found this link on ridley site http://data.ridley-bikes.com/sizes/sizes2011-en.pdf which would suggest I'm an xs (I'm a 170cm short arse and inside leg is 80cm - right between xs and s). when I try and find detailed info on xs I've found sites saying top tube lengths from 510 cm to 535 cm. I think this will vary from actual t/t length to virtual length as its sloping.

Does anyone out there have one and could offer advice. Can't test one locally and can't really build and try. If I was to go one way or the other which would you recommend - slightly too small or slightly too big? With small the worst is maybe slightly longer stem, more saddle setback and more spacers (giant headtube is 145, same as small, but xs is only 130 from what I can gather). too big goes the other way.

any suggestions?

hodge68

I feel for you, i spent ages trawling the net ref sizing of Ridleys, as i have a Medium boreas and im just over 6 ft and thought that sounded to small. But every forum i read said Ridley sizing was off and people got smaller in ridley than other makes. With regards to getting to big or to small, i really am no expert, but you as you say yourself you can change stem ect to size up.