Well, basically I agree with your approach in terms of philosophy.
But I have some remarks: if I have a steel frame of 1450g, like my frame for example, and you add 500g to the bike as an external pack, like you did in Livigno, this is not the same situation of having a frame of 1950g, this is sure.
The behaviour of the bike is mainly driven by the frame, not by the bike entirely, so if you have 1500g of frame and you add 300g (plus 20% of the frame wheight) you would really have big differences, both climbing and descending at high speed, because they are completely different frames.
The weight of 300g globally distributed on the frame implies enough to change your feeling with your bike.
Probably if you have 300g of difference between two frames, they are built with different tube series, as well.
Do you agree my remarks or am I overlooking some other aspects?
Tnx Dazza for your time, I'm really enjoining.
If we put 300 grams of material in the frame
that extra material will change the way the frame feels.
for example if I make one frame with .7 /.5/.7 mm tubes
and the same frame geometery and dimensions with tubes .8/.5/.8
then yes the frames will feel different to the rider
It is the extra material, not the extra weight that changes the feeling that the rider is feeling in the frame.
The extra material mass used correctly such as in the frame tubes is a good thing.
The extra weight (Mass) in theory will have effects when changing velocity or working against gravity. In real tests it is never possible to reproduce as the rider's power fluctuates in the tests. And even with SRM measuring data (I was fitting and maintaining the SRM equipment at the Australian Institute of Sport) we can not find the weight against power inputs measurable. In theory it must be there.
With a 75 kg rider and 7kg bicycle = 83 kg then .3kg is not much.
On one climb the rider may perspire .5 to 1.5 kg of water
then air temperature has effects on drag when testing
oh it goes on and on all the problems of detecting 300 grams when riding.
On a calculator it is possible
Out side when riding up a mountains science cannot measure as there is so many influences to the measurements. The rider may feel there is a difference, but actual velocity changes is not able to be detected against the input of power. (unless the extra weight approaches 3 to 5kgs, then it shows in the data measurements)
Hookes's law of Springs
http://en.wikipedia.org/wiki/Hooke's_law[url]http://en.wikipedia.org/wiki/Hooke%27s_law[/URL]
The same energy is stored in the strain (flex) of the stiff frame tube
as
in the strain (flex) of less stiff tube.
That energy still goes back into the chain as the frame tube returns to normal when the pulse of the pedal stroke reduces at 12 o'clock-6 0.clock
Some say that a flexible frame feels better to pedal on because of this.
I am not sure of this. I like the bike to track smoothly and with out wiggle.
I believe that very flexible frames behave badly when climbing and descending hard in rough corners. (also the fork is very important )
The extra 300 grams is better for performance.
The beautiful part of bespoke custom bicycles, in any material is that a good skilled and careful builder will take appreciation of the rider's circumstances and build a bike to meet the criteria.
There is a limit.
A frame as stiff as Granite is not going to be faster.