[skurfer333]

what is the "front centre" measurement reffering to?
also when the manufacturer lists the "top tube" and the "theoretical top tube" which one should I go by for determining which frame would be right for me?

 

[Ascentrek]

Front Center: sometimes measurements to the full length of just the tube, others go a little more by including the center of the abutting tube. i.e. seat tube measurement can include to the bottom bracket, or to the center of the bottom bracket.

Top tubes are being bent for standover height. the bend will create more length, but this doesn't reflect the 'as a crow flies' measurement between the top of the seat tube to the head tube. This is what a 'theoretical top tube' measurement is...

What is right for you is how you feel on it. how long of a stem do you want? You can always slightly modify the length with the seat rails. What type of riding do you want to do? DH or FR, you'll want to be a bit further back on the bike.... XC and climbing you may want to be a bit more stretched out. If you can, ride the differen't sizes.

 

[skurfer333]

I'm ordering one of the new norco's and I live in NC so its not like there are a lot of norco dealers around...