well, I ride comps and have my bike setup that way. You would think it would be setup super light, but it isnt.
First, wide rims are heavier, I have a mavic 321 on the front as its nice and wide, I also have a maxxis slow reezay tyre on the front for more grip, but this tyre is heavier than what a lot of treet riders run.
Then theres all the gears, mech, cable, shifer, it all adds up.
If I didnt do comps I could make my bike a lot lighter, well, actually, I am anyway.
Ti bolts, tubless, drilled front rim, lighter front tyre, so hopfully I can have a light bike again, but it wont be as strong, but its not really the riding that would break things like bolts, just over tightening.
so the answer is I m sacrificing reliability for weight, but my current bike is the opposite.