My racing wheels are 1,278 grams, aero, and it's a big difference when I put them on, as my training wheels are 1,910g. The light wheels are also far stronger than the heavier training wheels, and they don't have any weight limit because of that. Carbon fiber has a great stength-to-weight ratio, and tubular rims increase the strength even more, but of course, you pay for it. $100 for 1,540g is fantastic if they stay true and ride well.