My mojo frame will be here soon and I'll be trailing some seatposts. As I don't have any suitable posts I'm going to get a cheap one for testing. I'm exaclty 6' and will have a large frame.
Should I start with a zero set back or get a ~2.5cm setback. I will also be trying different size stems (which I do have) 100 vs 110.
Depends on your riding preferences. And your fit.
For normal proportioned riders on the 73 degree seat tube angle Mojo, 0 setback is best for climbing and efficiency pedaling long distance. And a set back seat position is easier to wheelie and aids rough technical for manualling up obstacle step-ups but climbing and pedaling is less efficient.
Also set back seats are used for XC riders with extra long upper leg bone length to keep to seat height low. A long stem, 120mm or even more, and low bars would be used to keep rider weight balanced over the pedals for climbing. But technical handling is compromised with long stems.
I was just doing a search on this yesterday. If I recall, this might have been the thread with some good info.
fore/aft saddle position
I know where I'm comfortable on my bike. And it doesn't seem to correspond to the standard seating position.
To be honest, I think it's a dynamic thing. And it's definitely a riding preference.
I've a zero offset, and my seat is all the way forward. But then, I'm a climber. 135 pounds. After trying the knee over pedal axle measurement, I realized that I've made the decision as to where my seat should be according to how I feel.
I have a suggestion. Try different positions. Push the seat way back, and see how you ride. Then go the other way.
I think you're smart to start off with a demo post, and just see. I guess in a word, experimentation will yield your answer.
Now, where do I ride today? Hmm, decisions...