For those guessing the wattage penalty of gravel vs aero bike....

[ripvanrando]

Controlling for changes in temperature, barometric pressure, and wind would be needed to do a valid real world test. Easier said than done. It is easy to see 10-20 watt variations day to day if a warm, humid low pressure system moves in and stalls.

[fourflys]

Originally Posted by ripvanrando

Controlling for changes in temperature, barometric pressure, and wind would be needed to do a valid real world test. Easier said than done. It is easy to see 10-20 watt variations day to day if a warm, humid low pressure system moves in and stalls.

Agree, that was my point of a larger sample size of rides (at least 3 months each), that would likely cancel out the variations of each individual day. Certainly wouldn't be perfect, but I bet it would be pretty close to give a pretty accurate avg...

[spoonrobot]

You can get as much real world data as you want, the juice is getting people to believe in it.

[fourflys]

Originally Posted by spoonrobot

You can get as much real world data as you want, the juice is getting people to believe in it.

too true... and in the grand scheme, it doesn't really matter... folks will ride the bike/components they want and, as long as they're riding, that's fantastic!

[ripvanrando]

If we can believe the SwissSide's numbers, by picking the right bike and tires for the course/road/trail, we potentially save 39 watts at 30km/h. A better way to look at this "revelation" is in terms of energy savings, 39 watts times 3,6000 seconds/hr is about 140,000 Joules or around 140 "calories" saved per hour.

On a long ride, that is a lot less food to have to carry and then to eat.

[KonaSS]

Originally Posted by ripvanrando

If we can believe the SwissSide's numbers, by picking the right bike and tires for the course/road/trail, we potentially save 39 watts at 30km/h. A better way to look at this "revelation" is in terms of energy savings, 39 watts times 3,6000 seconds/hr is about 140,000 Joules or around 140 "calories" saved per hour.

On a long ride, that is a lot less food to have to carry and then to eat.

True - but I would guess most people are not limited by the amount a food they could carry. This is 3 extra Clif bars for a 4 hour ride. I would guess actually increasing your average watts by 39 for 4 hours is going to be the challenge.

[ripvanrando]

Originally Posted by KonaSS

True - but I would guess most people are not limited by the amount a food they could carry. This is 3 extra Clif bars for a 4 hour ride. I would guess actually increasing your average watts by 39 for 4 hours is going to be the challenge.

I like decreasing it 39 watts for the same speed. 2 Cliff bars is my puke threshold.

[Likes2ridefar]

Originally Posted by KonaSS

True - but I would guess most people are not limited by the amount a food they could carry. This is 3 extra Clif bars for a 4 hour ride. I would guess actually increasing your average watts by 39 for 4 hours is going to be the challenge.

I prefer stinger waffles and have them opened already in my pocket so I can just slide them out and shove them in For really long rides I stack 6 or more in each pocket and eat one each hour coupled with drink mix in my water..can go a very long time, so yea I don’t think it’s a limiting factor either.

[fourflys]

Originally Posted by Likes2ridefar

I prefer stinger waffles and have them opened already in my pocket so I can just slide them out and shove them in .

little bit of a thread drift, but this perplexes me... I'm not a racer, so finishing a ride in xxx time doesn't really mean much to me. As such, the idea of stopping in a pull-off (maybe with something pretty to look at) to grab my snack is just part of the ride for me... not saying there is anything wrong with your method, just that it makes riding seem more like a job (gotta be as efficient as possible)... I suppose that could be the draw for someone, but just not me I guess. I will say I don't ride in groups either, so I can see where eating on the go might be required if that's what you do.

similar to the original discussion in this thread, I guess it comes down to individual riding style or goals. All good, just a thought...

[Likes2ridefar]

Originally Posted by fourflys

little bit of a thread drift, but this perplexes me... I'm not a racer, so finishing a ride in xxx time doesn't really mean much to me. As such, the idea of stopping in a pull-off (maybe with something pretty to look at) to grab my snack is just part of the ride for me... not saying there is anything wrong with your method, just that it makes riding seem more like a job (gotta be as efficient as possible)... I suppose that could be the draw for someone, but just not me I guess. I will say I don't ride in groups either, so I can see where eating on the go might be required if that's what you do.

similar to the original discussion in this thread, I guess it comes down to individual riding style or goals. All good, just a thought...

Historically I never stop be it one or 6 hours. Rarely for photos.

[Waldo62]

It's not a wattage penalty, it's a speed penalty. You put out however many watts on whatever bike. An aero-er bike allows you to go faster, a dirty-air bike slows you down.

[Mark McM]

Originally Posted by Waldo62

It's not a wattage penalty, it's a speed penalty. You put out however many watts on whatever bike. An aero-er bike allows you to go faster, a dirty-air bike slows you down.

This assumes you are riding alone, at your own pace. If you are riding in a group, you have to go at the speed the group is going. So if the others in the group have lower rolling resistance tires, you are paying a wattage penalty to ride with them.

[KonaSS]

Originally Posted by Waldo62

It's not a wattage penalty, it's a speed penalty. You put out however many watts on whatever bike. An aero-er bike allows you to go faster, a dirty-air bike slows you down.

Originally Posted by Mark McM

This assumes you are riding alone, at your own pace. If you are riding in a group, you have to go at the speed the group is going. So if the others in the group have lower rolling resistance tires, you are paying a wattage penalty to ride with them.

There is some tomato / tomato here. But technically, the study as presented is a wattage penalty. It is the amount of extra watts needed to hold 30 kph and 40 kph.

[rain dogs]

Originally Posted by KonaSS

There is some tomato / tomato here. But technically, the study as presented is a wattage penalty. It is the amount of extra watts needed to hold 30 kph and 40 kph.

It is the extra amount of Watts needed for a gravel bike, set up as a gravel bike, to hold 30kmph (and then two "faster than outbound/ or gravel descent speeds"), vs an aero road bike, with deep dish wheels on the road.

I'll patiently (very patiently) wait for the same bikes to be compared by swiss side on grade 4 gravel. I wonder if you could even get that aero road bike to 20kmph on grade 4 gravel???

[Andy sti]

So I did a 4 hour road ride on my "gravel" bike Saturday. Ride was solo. Tires were 35mm G-One Speeds on Belgium+ rims. The route had about 9 miles of smooth dirt that is fine on 25s. I was on my gravel bike because I wanted comfy tires and there is still a bunch of cinder on various sections of road. Plus it's too early for the road bikes to come out.

I did not feel particularly fast and I was keeping it pretty easy, z2 ride.

I averaged 19mph or 30.5kph.
My average power was 220w with an NP of 241w.

I would have been flying on an aero S5!