Live data from Hacker News

Aerodynamics of Gravel Bikes

renehersecycles.com

111–120 of 211 posts

Re: Aerodynamics of Gravel Bikes

#111

Earlier quoted context omitted.

Personally, I'd change the order. Coach first, body weight second. If there's one piece of equipment to buy first & ASAP, it'd be a powermeter and something to display the readout on. Riding in a group is of course great, but first You got to have the legs to catch up and then the body weight / metabolism to keep up. Having the core / flexibility to be able to spend hours in somewhat aero position doesn't hurt either…

> but first You got to have the legs to catch up and then the body weight / metabolism to keep up. Not just keep up, if you are riding in a group you need to be fit enough to take your turn on the front where you aren't draughting (at least if the group you are riding with is your team ). The actual team dynamics of professional road racing are fascinating, much like F1 they'll often pick the strongest and expect eve…

yeah, I've never really been into group riding / drafting on a competitive level. I'm mostly trying to avoid it, actually (more of a self-supported racing kind of guy).

Where I train (Paris, polygone de Vincennes) there are quite a few groups riding together, but not sure they'd switch places. I guess it depends on why You do what You do.

In my case, if someone wants to ride behind me, I don't mind (other than that it makes me a bit more careful when passing someone / turning corners). I'm there to work on my power output or cadence, not to get KOMs on Strava segments ;-)

Re: Aerodynamics of Gravel Bikes

#112
post #50

I am an out of shape former racer who has ridden his bike 10 times in the last two years. I have a dad belly and rarely work out at all. I recently did The Rift this summer - a 200km gravel race here in Iceland that people come from all over the world to race. I did it on a carbon cyclocross bike from my racing days with file treads. I felt like the light weight of my bike outweighed just about every gravel fad that'…

If most people are there just to finish then comfort should be more important than speed. In that case big tires and more relaxed geometry makes perfect sense.

Re: Aerodynamics of Gravel Bikes

#113
post #49

Earlier quoted context omitted.

Personally, I'd change the order. Coach first, body weight second. If there's one piece of equipment to buy first & ASAP, it'd be a powermeter and something to display the readout on. Riding in a group is of course great, but first You got to have the legs to catch up and then the body weight / metabolism to keep up. Having the core / flexibility to be able to spend hours in somewhat aero position doesn't hurt either…

There's a difference between weight weenie carbon and using carbon to improve ride feel and aerodynamics. I've got an old bike made out of Reynolds 853 steel that's lighter than my recent vintage full carbon bike.

The "ride feel" argument is something I quite frankly never understood.

I guess it's because I don't do competitive road racing (more of an ultra / bikepacking sort of guy). When I was shopping for my current frame (Kona Rove), I picked up the steel version mostly for maintenance / mechanical reasons more than anything else. Don't see much of a difference in "feel" from my old aluminium road to be honest (other than what's caused by the different geometry / fit).

I'd like to build up some chinese carbon frame next year just for fun, so we'll see. Maybe I'll change opinion then.

But yeah, I 100% agree that the aerodynamics on modern frames is significantly better. Just not really at the speeds at which I end up riding and with the amount of gear / packs I end up putting on the frame / handlebars.

Re: Aerodynamics of Gravel Bikes

#114

Earlier quoted context omitted.

Personally, I'd change the order. Coach first, body weight second. If there's one piece of equipment to buy first & ASAP, it'd be a powermeter and something to display the readout on. Riding in a group is of course great, but first You got to have the legs to catch up and then the body weight / metabolism to keep up. Having the core / flexibility to be able to spend hours in somewhat aero position doesn't hurt either…

Yeah but carbon gives you cred, and basically _buys_ you speed. Losing weight is effort. Sarcasm over, one of the funniest cycling stories i ever encountered. My work had a little low-key "bike club", a few guys cycling on warm evenings. One of the partners was a key member so over time non-bike guys started wiggling in for networking purposes. One guy, with no clue how to ride, drops 2k++ on a full carbon bike, high…

The sad thing is that $2k barely gets you a carbon frame with low end components now. A mid tier bike is maybe $5k, and high end can easily be more than $10k.

Personally I really don't get why anyone would pay $10k for a bike. Amateurs won't benefit nearly enough to make it worth it, and pros are of course sponsored.

Re: Aerodynamics of Gravel Bikes

#115
post #50

I am an out of shape former racer who has ridden his bike 10 times in the last two years. I have a dad belly and rarely work out at all. I recently did The Rift this summer - a 200km gravel race here in Iceland that people come from all over the world to race. I did it on a carbon cyclocross bike from my racing days with file treads. I felt like the light weight of my bike outweighed just about every gravel fad that'…

Why don't you actually do some math, or experiments, rather than just telling us you have doubts? This is all really easy stuff to answer. For instance. 75kg rider + bike. Make the bike 1kg lighter. Go up a 8% grade for 1 kilometers at 300 watts Time saved by 1kg weight reduction? 30 seconds out of 40 minutes. Or suppose we add 300grams to the frame to make it aero, which is typical. If that reduces the CdA by .02 ou…

I know nothing about typical bike timings, but I was struck by that. Does it really take 40 minutes to go 1 km at an 8% grade? Would it be faster to get off the bike and walk? When you're not rolling, you don't have to output power to fight your own weight trying to roll back - the friction between your shoes and the ground counteracts that. (I assume a real race doesn't allow you to walk, just batting around thoughts hypothetically here.)

Re: Aerodynamics of Gravel Bikes

#116
post #6

These in-depth scientific studies always seem to neglect the weight and aerodynamics of the RIDER. That is surely the biggest factor when it comes to speed and efficiency.

It's always funny with people having paid $10k extra to save a kilogram on their bike, and then show up on the Sunday group ride with a beer belly. But I think these articles and study are mostly written for / paid by professionals, and they don't have that much more weight to lose. But reading "The secret race" by Hamilton (one of Armstrong's team mates), they do focus obsessively on it. They would often ride for ho…

When framed that way, it seems odd, but is it so strange that someone with means spends $10k on their hobby? That's really what it comes down to, more so than the weight-savings. If you like riding bikes, and have the money to spend on it, why not spend $10k on a fancy bike?

Re: Aerodynamics of Gravel Bikes

#117
post #68

Earlier quoted context omitted.

Reminds me of this bicycle subreddit where they spend thousands on bikes and cosplay attires to get smoked by 60+ years old dudes on 40 years old bikes As a casual rider you'll be the bottleneck for years before your gear matters even the slightest

There’s also a saying in bike communities, along the lines of, it doesn’t get easier you’ll only ride faster. Riding a heavy bike with no aerodynamics will lead to building strength faster. While it can be a bit frustrating if you’re new and riding in a group, joining more beginner friendly groups and upgrading the bike later is much better overall. It is however really important to get the posture and pedaling techn…

> push-only instead of a push-pull

My body never got this until using fixed gear. The whole circle is important.

Re: Aerodynamics of Gravel Bikes

#118
I ride a Trek Domane 5 AL which allows spacing for a 48mm tire ( odd for a roadie ) - so I put a 48mm gravel tire on it and started riding it on light gravel. Works very very well. Carbon would be even better but Id still be waiting on it to arrive from the factory alas the aluminum version will have to do. The best bike in the world is the one you have in the garage to ride today.

Re: Aerodynamics of Gravel Bikes

#119

Earlier quoted context omitted.

Dutch style bikes are perfect for casual city riding, sight seeing and well, riding slowly. Usually when you are commuting and you have more than a couple kilometers to ride you want to do it faster. Dutch omafiets are really bad in term of aero.

Would you happen to know the age at which Dutch commuters (shopping) start to give up cycling? Do people regularly cycle past 90?

I don't have that exact figure, but the 65+ age group has a higher bicycle mode share than 26-45 and 46-64: https://www.researchgate.net/figure/Bicycling-share-of-trips...

Re: Aerodynamics of Gravel Bikes

#120
post #50

I am an out of shape former racer who has ridden his bike 10 times in the last two years. I have a dad belly and rarely work out at all. I recently did The Rift this summer - a 200km gravel race here in Iceland that people come from all over the world to race. I did it on a carbon cyclocross bike from my racing days with file treads. I felt like the light weight of my bike outweighed just about every gravel fad that'…

Why don't you actually do some math, or experiments, rather than just telling us you have doubts? This is all really easy stuff to answer. For instance. 75kg rider + bike. Make the bike 1kg lighter. Go up a 8% grade for 1 kilometers at 300 watts Time saved by 1kg weight reduction? 30 seconds out of 40 minutes. Or suppose we add 300grams to the frame to make it aero, which is typical. If that reduces the CdA by .02 ou…

You're forgetting the effect of exertion on the rider under heavy loads like climbing.

I've ridden heavy bikes, and I've ridden light bikes. Light bikes feel better, rotational weight mattering more than anything else.

Post reply on HN