Bianchi Oltre XR2 Setback

[3Pio]

Hi there.. Does someone have idea what setback Bianchi Oltre XR2 have in different dimensions? Im interested specialy about setback of 53 and 55 size

Greetings

[GT56]

not sure what you mean;

is it b1 minus x as in Bianchis geometry-tables ?

[3Pio]

not sure what you mean;

is it b1 minus x as in Bianchis geometry-tables ?

Is that part of the top tube, but it's not caluclated just with b1 minus x, and dont know how to calculate it..

For example, Pinarello put this in their geometry chart

http://www.pinarello.com/en/bike-2015/r ... 8-geometry

In this chart is I value (for example on 53 cm frame is 149 mm)

So how to find out about Oltre XR2 in 53 and 55?

[wheelsONfire]

Oltre size 53 = 152mm
Oltre size 55 = 162mm

What you do, you deduct the effective top tube length (measured horizontally)with the reach number.
So, B1 - X is your answer.

[3Pio]

Oltre size 53 = 152mm
Oltre size 55 = 162mm

Im afraid this not true, becouse setback (u have a straight line from bottom bracket to the top tube. From that intersection we are measuring the distance to the centar of seat tube.. So i need this value...) is not calulated just B1-X (based on geometry chart of Bianchi)

For example if we see the chart from pinarello

http://www.pinarello.com/en/bike-2015/r ... 8-geometry

And for exaple for 53 cm we calculate same way as B1-X (in Pinarello Case would be L-Reach = 159. But the real value in this table is 149. )

So we still need proper setback values for Oltre XR2 53 and 55


I guess for 55 would be somewhere around 149mm, and for 53mm would be probably 140 or 143mm.. But this is just guessing, i still cant calculate the real values that i need

Thanks anyway

[DvanW]

Wheelsonfire is spot on, exactly the same as the pinarello measurement this way.

[wheelsONfire]

If that is the case, you should probably use the sloping angle.
That is BS instead of B1.

That would give you 140mm and 150mm.


3: If you don’t have the published seat tube angle for your frame and you don’t have an accurate protractor or “Angle Finder”, you can measure setback. To do this, hang a plumb bob from the top tube so it passes through the center of the bottom bracket axis. Put a piece of tape on the top tube to mark the spot. Measure horizontally from this line back to the frame size point. That is the frame setback. Seat tube angle can be calculated from setback and seat tube length or you can simply compare setback directly.

[3Pio]

If that is the case, you should probably use the sloping angle.
That is BS instead of B1.

That would give you 140mm and 150mm.


3: If you don’t have the published seat tube angle for your frame and you don’t have an accurate protractor or “Angle Finder”, you can measure setback. To do this, hang a plumb bob from the top tube so it passes through the center of the bottom bracket axis. Put a piece of tape on the top tube to mark the spot. Measure horizontally from this line back to the frame size point. That is the frame setback. Seat tube angle can be calculated from setback and seat tube length or you can simply compare setback directly.

That can work , but cant find Oltre in 53 cm to do it

[jekyll man]

cant you use trig to work it out?
The seat angle is 0.5° different between the 2 sizes, and accounts for a lot of the difference in TT length

[GT56]

why do you want this so exact anyway ?

[3Pio]

why do you want this so exact anyway ?

Becouse i think its one of the most important thing on bike geometry, and based on this u can predict where u'll saddle would be. Specialy important since i have a long femurs (so need a lot of setback), and in same time i need short reach.

[GT56]

why do you want this so exact anyway ?

Becouse i think its one of the most important thing on bike geometry, and based on this u can predict where u'll saddle would be. Specialy important since i have a long femurs (so need a lot of setback), and in same time i need short reach.

doesn't the seat tube angle give enough of a clue ?

[3Pio]

why do you want this so exact anyway ?

Becouse i think its one of the most important thing on bike geometry, and based on this u can predict where u'll saddle would be. Specialy important since i have a long femurs (so need a lot of setback), and in same time i need short reach.

doesn't the seat tube angle give enough of a clue ?

Obviosly not.. But of course if u can calculate this setback length based on angle i would appreciate to share it with me, becouse i have maybe idea, but need detailed setback length

[GT56]

why do you want this so exact anyway ?

Becouse i think its one of the most important thing on bike geometry, and based on this u can predict where u'll saddle would be. Specialy important since i have a long femurs (so need a lot of setback), and in same time i need short reach.

doesn't the seat tube angle give enough of a clue ?

Obviosly not.. But of course if u can calculate this setback length based on angle i would appreciate to share it with me, becouse i have maybe idea, but need detailed setback length

how far behind the bottom bracket do you want the saddle tip to be, and of course what is your saddle height

if you already know what saddle, that would be helpful too

[3Pio]

why do you want this so exact anyway ?

Becouse i think its one of the most important thing on bike geometry, and based on this u can predict where u'll saddle would be. Specialy important since i have a long femurs (so need a lot of setback), and in same time i need short reach.

doesn't the seat tube angle give enough of a clue ?

Obviosly not.. But of course if u can calculate this setback length based on angle i would appreciate to share it with me, becouse i have maybe idea, but need detailed setback length

how far behind the bottom bracket do you want the saddle tip to be, and of course what is your saddle height

if you already know what saddle, that would be helpful too

I use two saddles: One is Selle Italia SLR Carbonio Flow (seem that this would be my main saddle), and Specialized Romin Evo Pro 143mm

Saddle height measured from bottom bracket, and using 172.5 cranks is 71.5 cm

Seatpost is with 25mm sb

I need tip of the saddle to be about 6 cm behind bottom bracket (and if u can tell me what is the maximum that i can get "tip of the saddle behind bb" on 53 and 55 even better )

Thanks