Comparing Vendetta & DF power outputs

[RojoRacing]

Had a chance to ride with a rider who is a notch stronger then I today and strangely enough we averaged the exact same wattage over a 17 mile race segment. I started the segment one minute after Chris and we finished together. I caught him in the 7th mile and we sat on my wheel the rest of the way. @LarryOz is always asking for me to compare my V efforts against my DF efforts but there's so much change in the wind
out here that you just can't compare day to day. Now I know this comparison has it's own variables like the fact I rode the loop one minute faster as well as the fact that Chris drafted me for the last 10 miles but to have the exact same avg watts is interesting. We also have to consider that each of our power meters maybe read 20-30 watts higher or lower then the other per Larry's recent testing.

Here are the two links of each of our segment efforts.

Mine
https://www.strava.com/activities/755810642/analysis/680/2991
Chris
https://www.strava.com/activities/755901133/analysis/3261/5635

 

[hoyden]

Looks to me like the Vendetta vs DF power difference is within the signal/noise ratio of the power meters for two otherwise well matched bikers.

 

[RojoRacing]

Looks to me like the Vendetta vs DF power difference is within the signal/noise ratio of the power meters for two otherwise well matched bikers.

Except the V was 60 seconds faster and probably a further 20-30 seconds more so if Chris didn't draft me the last 60% of the route. Chris has a TT bike he's been dialing in for some kind of special TT race where he mentioned he has to hold 380 watts for 4km or something. I wonder how much better he could draft me on the TT bike and if being my aero himself would make up most of that 60 second difference.

When you bring up both rides as a whole and isolate a few of the straitaways toward the end where I'm holding a steady effort over 300 watts you will see both Chris and I are still within a few watts avg of each other even when going all out at 360 watts for a few mins.

Still for a proper test you need two riders of similar build and strength riding together side by side no drafting on the same day same ride same conditions with power meters calibrated to each other. All of that is hard to do for us with normal day jobs.

If I'm this fast on the V just imagine how fast an actual pro peloton rider would be?

 

[hoyden]

All of that is hard to do for us with normal day jobs.

Collecting the comparable objective data is daunting, and it's interesting to note that the accumulating subjective data highlights the Cruzbike's exceptional performance. Thanks for sharing your experience. You are pushing the boundaries of performance and showing Cruzbike's capabilities.

 

[trplay]

I'm interested in the differences in CDA using the thor seat compared to the stock seat. Could you be kind enough to measure from the top of your helmet, across the chest , lowest part of hiney, and the highest point your toe goes on the pedal stroke in inches (and anyone else who also uses a non stock seat)?

 

[ratz]

Take the bikes to the same hill that you can roll down without running out of road.
Stand next to each other and lift your feet.

If the bikes roll to a stop at the same spot; then you can compare power numbers
If one bike beats the other then we have to measure CdR and CdA and do math to compare the power need to move down the road.

You can say that really CdA is the only thing that matter but if we ignore CdR then your 20-30 becomes 30-40 watts error or rather +-15 / +-20 and then theres no point in comparing to much range.

I think I frustrate people now and then but here I go. Power meters really only do two things well. But it's a great thing: (1) The let you train consistently and measure your output regardless of weather. For a single athlete on a single bike they are a consistent measure. (2) The let you measure the impact of changing a single variable relative to you; which can be used for bike optimization. Power Meter and Rider must remain the constants.

What they really don't do is let you compare numbers to other riders; because you can't hold enough things constant outside a wind tunnel. Two riders can't ride on the same physical power meter, at the same time in the same conditions. So comparing numbers to someone else is really just folly so don't get too hung up on it; to much uncertainty in the variables.

Compare optimization on your equipment with your power meter;
Compare Rider performance with a finish line....
Save up for time in the wind tunnel

Of course the first thing I did was go look at the strava data and compare rider to rider

 

[RojoRacing]

Right? I mean how many times have you done a ride with another rider and ended up with identical watts for 39 mins? That begs to be studied even if you know it's in vain

 

[ratz]

Right? I mean how many times have you done a ride with another rider and ended up with identical watts for 39 mins? That begs to be studied even if you know it's in vain

As long as we know we are bragging about the speed of our fast ball from the days before radar guns, then it's all in great fun. I'm not a competitive person; until 3 feet off the back of someone's wheel then to hell with the theory....

 

[PeteClark]

As long as we know we are bragging about the speed of our fast ball from the days before radar guns, then it's all in great fun. I'm not a competitive person; until 3 feet off the back of someone's wheel then to hell with the theory....

Q: What's the definition of a bike race?
A: Two bikes going in the same direction.

 

[ratz]

Ignorance that the race is occurring doesn't mean you didn't lose.

 

[LarryOz]

Q: What's the definition of a bike race?
A: Two bikes going in the same direction.

Heck - I don't even need another person to have a bike race - just 2 power meters! (Hub based, and pedal based in my case!)

 

[RojoRacing]

Heck - I don't even need another person to have a bike race - just 2 power meters! (Hub based, and pedal based in my case!)

Your the type of guys who when using google maps to navigate to a destination thinks "challenge accepted" when it gives you the ETA.

I have never lost in a race against google

 

[LMT]

As Ratz mentioned to get a proper reading you'd have to go into the a wind tunnel. The V20 has got a lower CdA then the bike, I'm presuming this based on the Diamond Back Andean having a CdA of 0.221? I think it was in a promo video that I saw a few weeks ago, and this would have a lower CdA then the guy you was riding with. Larry's testing with the V20 came back with 0.154 which in line with 0.155 with what I got off a power data website.

 

[trplay]

Hmm is this going to be like pulling hens teeth? I'm just curious how much if any the modified seat puts the upper body into the open air. (oh and I forget the distance of the handlebar to the ground).

 

[McWheels]

Hello Chaps, I've been out looking, and there are a few scholarly articles out there you might be interested in.

Page 10 of this one, right hand side

A fairly recent article, but mostly theoretical. Nice that they support the FWD MBB concept.

And the one I was looking for all along. Page 5. I particularly liked the influence of the winter jacket!

And finally, something I've posted elsewhere, but the tyre rolling resistances have been done for you.

Therefore, is there a case for a Race-Only Machine in the vein of Windcheetah's FRO? I think we all agree a low-racer isn't great on the road, but on the track...?

 

[trplay]

Thanks, the air drag vs seat back angle at first look appear to support my thoughts. I do think our fast guys can get faster with a little tweaking of the vendetta.

 

[DavidCH]

If there is a fast peloton going uphill , think twice about passing it.

It was weird. A lot of expensive bikes wizzed pass me as I reached an intersection. These guys were motoring. 42kph. And then I said did I want to?

I only had plans of going out for a casual 150watt burn.

I eventually caught up with them and got my breath back. Then at a circular/roundabout things got more interesting. The riders at the front did a loop so that the riders behind could catch up and I found myself right in the middle of it.

So I decided the wolf amongst the pack had to get out. So plunked on the power and I thought I got away then I saw two DF riders break off and catch up with me.

Now if I had that titanium vendetta. It might be a different story.

 

[ak-tux]

Interesting comparison between DF and Carbon MBB up a 0.9Km road section of 9% grade by Marco Ruga. To ensure equal weight between the two bikes he carried some water in a "camel back" bladder on the DF.

https://biciclettereclinate.blogspot.co.ke/2017/10/il-test-dei-test.html#more

 

[RojoRacing]

I'd like to see his results on a 20-40 min climb. He'd also need to use calibrated power meters on both bikes to be sure one isn't 20 watts lower then the other. I've done this with my vector pedals against my neo trainer on both bikes. And yes a power meter is critical to prevent a biased rider from trying harder on their preferred bike then the one they aren't as comfortable with.

His results mirror my experience with small climbs. It isn't until you reach longer climbs with steep kickers that the difference becomes greater because you can't change position on the bent.

 

[ak-tux]

...

His results mirror my experience with small climbs. It isn't until you reach longer climbs with steep kickers that the difference becomes greater because you can't change position on the bent.

Good point. Yes, changing positions on the bent is the one major limitation. However, I find that I can achieve minor changes by sliding deeper and forward on the seat allowing me to "drop" my heel or sitting up a little every once in a while. That said it's still not the same as getting out of the saddle on a DF to stretch a little.