In part 1 we looked at up and down, here we will consider the effects of forwards and backwards or 'fore and aft' as is often referred to.
THE WARNING.Firstly, the information here is just that, don't go rushing out to your bike and risk injuring yourself by moving your seat post up or down or both - for the more particular of you, you will end up with a scratched seat post to upset you before you get as far as the risk of injury a maladjusted Saddle Height can bring.
The purpose of the information here is more to raise general awareness rather than be prescriptive, the advice as always is to make sure your bike fits you as best it can.
Now that is out of the way let's move on.
When you look at the connection of your saddle to the seat post there will almost certainly be a bracket that allows some form of adjustment for backwards and forwards, some specialist cycles such as the Cervelo S5 even have two separate attachments for the saddle bracket.
Considering the additional engineering required to do this, it would be sensible to assume that there is some benefit to be gained from the saddle position.
In basic terms once you have the correct saddle height, the forwards backwards position of the saddle will help determine the riders position relative to the pedaling mechanism of the bike. Too far forward and there is a risk of injury and too far back and there is a loss of power and efficiency, not to say that this would not result in injury also.
The ideal position in road cycling, more on TT in a minute, is found with the knee roughly over the centre of the pedal spindle axle with the pedals parallel to the ground, if assuming a flat supporting surface.
This Knee over Pedal ideal has been used for decades and does have merit, however, as most methods used to measure this need to be static, the application is limited. After all do you sit still when you ride your bike and do you adopt differing positions depending on your effort level?
For this reason the Retul System used here is dynamic taking measurements with the rider working at different effort levels. In this way the fitter is able to see how the rider moves around on the bike and discuss this with them to create the most suitable fit.
With regards TT positioning, this is somewhat different. As the rider is aiming for a lower, fixed and ideally more aerodynamic position with the torso rotated forward the saddle is also moved forward to help accommodate this, with the knee often being up to 90mm further forward relative to the 'standard' road position. Again this may alter from rider to rider and also at different effort levels.
The best position for the cyclist is often a form of compromise between the bike the rider and the goals of the rider, by completing the pre-fit questionnaire the cyclist is able to provide the fitter with information to help the conversation develop during the fit.
Once the saddle position is reached the front of the bike can then be addressed, looking at stem length, handle bar height and position.