Mathematician needed

[tjk23]

Trying to compare seat tube angles in relation to setback and choice of seatpost. I have ridden a zero setback post on all my bikes until now. My previous bike had a seat angle of 73.5 and the new bike has an angle of 73.8. Is this enough to affect the seatpost?

[tuscanyswe]

No 0.3 of difference in sta is not enough to force you to change seatpost unless you were allrdy at the very edge of the saddle rails position in the clamp.

How much the STA effect your position depends on your saddle height also. More if you are tall than if you are short..

A good rule of thumb i use is 1 degree on sta is approx 1cm in difference in reach. It works out close enough.. so your 0.3 degree of change in sta would amount to approx 3mm reach difference.

[John H.]

This- it is about 3mm at 73cm saddle height- Slightly more at taller saddle height, slightly less of lower.

No 0.3 of difference in sta is not enough to force you to change seatpost unless you were allrdy at the very edge of the saddle rails position in the clamp.

How much the STA effect your position depends on your saddle height also. More if you are tall than if you are short..

A good rule of thumb i use is 1 degree on sta is approx 1cm in difference in reach. It works out close enough.. so your 0.3 degree of change in sta would amount to approx 3mm reach difference.

[tjk23]

Thanks.