Originally Posted by
HTupolev
No it isn't.
When you're doing curls, the weight you're using is pretty much the entire load. Doing a curl with a 25-pound weight requires applying 67% more force than doing a curl with a 15-pound weight.
When you're cycling up a hill, you're carrying yourself in addition to the bicycle. If you're a 170lb rider, then a 25-pound bicycle versus a 15-pound bicycle is really 195lbs versus 185lbs, which is more like a 5% difference. (And that's if we're only looking at gravity. Rolling resistance and aerodynamic drag don't disappear on hills.)
Does it matter? Sure. Does it have a measurable effect? Sure. But if we're comparing it to curls, it's more like using a 19-pound weight versus a 20-pound weight.
This is a little bit complex to answer, because if you're looking for extra performance, most of the low-hanging fruit wouldn't really require modernization. The biggest thing slowing you down is probably those Marathons; they're tough, but they have very high rolling resistance. If you're living next to mountains, you could probably make a big quality-of-life improvement by switching to a triple crankset with a small inner ring, regardless of drivetrain modernization.
But a modern bike would immediately address a lot of things. You could save 8+ pounds with a price point <$2000. Modern road bikes generally come with lower gears than what your Traveler has. Modern bikes use 700c wheels which offer better tire selection. Modern road bikes come stock with brakes that are more powerful and stiff than the Dia-Compe single-pivots on the Traveler, and the brake hoods on modern bikes are easier to actuate the brakes from. Modern road bikes generally come with the shifters integrated into the brake levers, which most people find makes shifting more convenient, and which makes it easy to shift while riding out of the saddle.
Thanks for taking some time to write out a meaningful answer.
So the Marathons. I kind of like them, but can't say I've tried anything higher-end. There isn't a lot of selection in 27.25. I had some Vittoria's on there before and they were junk. What I've appreciated about the Marathons is I've had no flats in many, many miles. I ride them on pavement and hard dirt and gravel. On my wife's bike, I put the Schwalbe Big Ben balloon tires. It's just a comfort, hybrid type bike (a 2020 Cannondale). Those tires seem pretty tough too, though understandably pretty darn heavy. Schwalbe rates their rolling resistance as remarkably low. What should I look for in tires that will make the most of a new bike? I realize I may need two sets. With my current bike, I'm riding road, gravel, heck I even ride the beginner slope-style course with my adolescent kids (they have 24" MTB's that they've just about grown out of and they're not into bikes enough to upgrade yet). Obviously, I'm not into slope style with the Schwinn, but it's not fragile.
Guy on Craigslist has a S-works "Epic" hardtail with lots of gears, carbon everything and two sets of wheels (Roval). It must not be the lightest because of the fork, but he says its 19 pounds. I could use one set of wheels for road tires and the other for offroad climbs. It's a 29er or 700c.
Just like I'm not into slopestyle, I'm not into downhill single-track racing. My current bike is obviously not a cutting edge road racer either. On the other hand, I can do modest bike touring, road riding, gravel tracks, dirt roads... I can definitely see lower gearing or more gears opening up some climbs in the mountains both on-road and off.