One thing is for sure, a lighter bike is a faster bike.
I recently sold my old mtb and got a sirrus pro that's about 8 lbs lighter. I recon I gained almost 2mph.
Was going to say youll get to a point where all the bike weight saving in the world will make no odds. Its easier an cheaper to loose weight yourself than off the bike.
can anyone tell me what sort of speed gain if any I could expect by switching from 28c tyres to 25c ?
Really? If its so easy to lose weight then why are we an obese nation with a multi million pound weight loss industry?
It is way way easier to go out and buy a light bike lol.
Cheaper is not really a thing, as if you lose weight you will probably want a light bike all the more, and then there is all the new clothes that you will have to buy!
An 8lb lighter bike will feel much better and more noticable than losing 8lb in bodyweight IME.
The best solution is to do both of course (if you are overweight).
It depends what bodyweight you are losing the 8lb from though of course.
Basically the goal is to be not overweight, and ride a light (well specced) bike.
Its not one v the other, its both!
And leave the financials out of the equation.
If you cannot or (more likely) do not want to spend the money, then just don't.
Bitching about it just to make yourself feel better about spending your money on other things is v sad.
can anyone tell me what sort of speed gain if any I could expect by switching from 28c tyres inflated to 90psi to 25c 110psi?
I ride my 28s around 18mph on the flat at a medium pace.