ANOTHER average speed thread..... sorry
 

I think I'm taking this "dead horse" topic from a different angle. I'm not asking if my average speed is good, or trying to impress anybody with my speed (or lack there of). I'm analyzing my average speed with all of my bikes over a specific Strava segment. I'm posting this to find out if I'm leaving any holes in my 'logic' as I analyze bikes and there relative speeds. Please look it over and let me know your thoughts.

For starters, I selected a segment near my house that I ride a ton (354 times). The segment is long enough (1.4 miles) and diverse enough (hilly and twisty) to be a good caparison.

Here is what I came up with:

http://bikeforums.net/attachment.php...hmentid=501119

I forgot to include a header row, the right most column is number of rides over the segment; to the right of Total Dist is the sum of distances for the count; to the left of the Total Time is the sum of times for the count; and Ave Speed fields are calculated by dividing Total Dist by Total Time (not averaging the average speed).

For reference, here are the bikes in this analysis:
http://bikeforums.net/attachment.php...hmentid=501120

Left to right: Kona Dew Drop, Mondonico, Felt Z85, Marin Nail Trail, Surly Pugsley, Globe Daily

My surprising take away is that the Felt (newer AL frame) has such an advantage on the Mondonico (classic steel frame). The Mondonico is the new (to me) bike and that may be the fact that I haven't ridden it as many times. Plus I spent last summer making lots of little tweaks and upgrades, so many of the rides were shake-down rides, not aggressive rides.

Steel is real ... slow .... ;) Science proves it.

(That'll get things started.)

T%he Felt has some red on the frame.

So?

It's even in bold to help you.

This project started out of an interest to see how the Felt and Mondonico compared. I honestly expected them to be on even footing. 5% to 10% difference is a little shocking.

My only question about your methodology is whether you're starting the segment from a dead stop and/or ending it with a stop. If so, your average speed may overly weight each bike's acceleration/deceleration profile (unless your riding style is to stop every 1.5 or so). Your method will tend to favor a bike that accelerates/decelerates quickly.

It really depends on your typical ride. When I commute, I stop and start every half mile or so. When I do a road ride, I can go 5 or more miles without a stop.

It's fun to have so many bikes to compare!

Nice point, and that was part of my consideration. The segment does not include any stops. Some of the rides are commutes, some are fitness rides, some are sunny days with a tailwind and some are snowy with a headwind. That's why I decided to try the 80/20 rule - kinda - to see overall, good day, and best days.

And thank you, I'm very lucky to have a collection of bikes. My garage is large enough that I don't need to get rid of old bikes for space, and I have been lucky enough to have two of these bikes to come to me at no cost - one was a gift and one was a prize.

All the data seems reasonable to me. The fact that there aren't as many rides with the Mondonico as with the Felt certainly can introduce bias, so I'd suggest riding more and then revisiting the data. But I suspect you'll find fairly similar results.

Afterthought: the question might be more about "how do you compare bike performance?". Other people have a number of similar bikes in the stable. If you have multiple bikes, do you you geek out and look at stats to understand which bike is faster/better? What are the measurements/methods you use when understanding your bikes' performance?

I strongly suggest you hire an independent bike tester to make sure all the tests are thorough and unbiased. PM me and I will send my resume.

HA! I spent 10 years selling mechanical test equipment to a variety of industries, including the bicycle industry. In fact during my years working with that company, my co-workers got me back into biking (lots of dedicated bikers). Some of these guys are uber-engineer and bike-geeks, it's one hell of a combo! I'm not an engineer, but working with engineers for decades (and some of the brightest), some of the thought processes rubbed off on me. So if you think your resume can compare with Rob's, you have the job: The Tularis (Not a bicycle, but give you a favor of the people I worked with)

This is pretty interesting, espeically your results of new Alum vs old steel. What's the weight difference on the bike? Gearing difference? If the old bike is 6 speeds and the new is 11, you would likely find a better "sweet spot" in your pedal cadence that might give you the edge- I could easily see that making a few % difference. However, take the wheels and groupset off the Felt and put it on the steel frame, and I think the difference would be negligible. Any thoughts?

How do you know you rode them equally hard? What are you using to measure power?

A more scientific test would be to get a PowerTap wheel and collect average watts and total Kj for your specific routes on different bikes. Average and weight all the data and then see which is faster for the amount of power. You need to try and maintain equivalent positions on similar types of bikes and collect data on days with similar wind conditions.

I have nothing to add except that it's cool that you own a Mondonico.

This^^^. I can post a 'wish list' of speeds that looks similar, but my wish is to ride my tandem fatbike solo faster than my time trial bike. Even if we take you at your word that you had the same perceived effort for all tests, all your chart shows us is that you rode certain bikes at certain speeds. The fact you were wearing a half-unzipped windbreaker one day and a skinsuit the next, or that you forgot to top up your tires with CO2 one day on your road bike, is not included.

I like geeking out on data, probably more than most people. I've got a power meter, use Golden Cheetah, etc.

For a while, I had two Cervelos. How their performance compared was pretty obvious to me without any real testing. I was always satisfied with my direct, unscientific observations (which were exactly what you'd predict).

Right, I'm kinda cheap and do not have any power sensors.

That's why averages over a number of rides and looking at top 80% and 20% - it helps eliminate the day I was riding into a head wind or it was pouring rain or I was just tired and dragging a$$. Same rider, same course allows for a good amount of leveling (no skin suit in my closet). And power is the final word, so without power, I feel I've done a good analysis.

The whole point of multiple rides isn't about how fast you are at a given power output. But how fast you are on a bike. Does a bike allow you/encourage you to ride harder? Does it make no difference in the real world?

One often-repeated argument on these forums is that, while a lighter/more aero/newer bike may be faster in theory, you will not be able to see that in the real world. Hypno Toad's data provides a good glimpse into that. You can see that his fatbike is significantly slower than his road bikes on that segment. Whether it is because of weight, rolling resistance, aero or simply because he doesn't feel like pushing it when he is on the Pugs doesn't matter.

Does anybody really think a fatbike is as fast as a road bike with skinny tires in the real world? I haven't seen that come up in the forums. I certainly can tell the difference between even relatively similar bikes, such as when I switch with my girlfriend and ride her Cross bike with cross tires, and she rides my road bike. I have a really hard time keeping up with her, even though I can easily blow by her with little effort when I'm riding my own bike. I think the most interesting thing about the data is the difference between relatively similar bikes, where smaller variances would make a difference.

So a couple recent posts make it clear that there is a theory that power sensors are the ONLY way to analysis and compare bike performance. However, the riders performance is measured by the power meter. So I could be putting out a lot more power to push the Pugsley at 14 mph than the Felt at 20 mph.

However, the speed of the bike is the true OUTPUT of the bike. The TdF doesn't give the yellow jersey to the rider with the best FTP... nope. Therefore, with competitive cycling, speed is the yard stick. And for a simple analysis of my bikes, looking at average speed over a specific section of road has merit. Comparing the Pugsley to the Felt is pointless, it was just easy to include all bikes and mildly interesting.

I am comparing only one rider, but across 350 rides. That is a statistically significant number to eliminate the day I didn't air up, or was riding with the jacket open, or the day I stopped to talk with Luke (his house is on this segment), or that day my wife was riding with me and wanted to see the open house on this segment.

Additionally, if you are looking at the data, the top 80% of rides per bike eliminates the previously listed reasons for a slow ride. And looking at the fastest 20% is looking at the rides when I was feeling strong, riding aired up tires, and likely had a tail wind. I would say that the Kona is the best example of this analysis, it is the daily commuter and rides in some terrible conditions, so it's number change dramatically when removing the bottom 20% and looking at only the top 20%.

My only real issue with the data I have is the smaller sample for the Mondonico. For the 2016 summer, I will be riding the Mondonico and Felt a lot more (I moved to a home office last year). And I will make a point of pushing this segment with both bikes to see what I can do to increase the sample size.

I used the Pugs to provide a clear example of how he was slower on one bike than other (although I have heard people argue that fatbikes are faster than road bikes on the road. Some people do believe fatbikes are the best thing ever) I agree that it is more interesting to see the abg speed difference between two road bikes. But I think the data is valuable on its own, even without power meters because it shows the actual effect of a bike.

Which bike do you enjoy riding the most? Which is most comfortable on a long ride? Which is the most fun?

I do. When you're riding in several feet of snow. Road bike is faster on bare pavement, mountain bike is faster on rocky, rooty single track, fat bike is faster in deep snow. All three are real world conditions. In other words, these are the best tools for different jobs, and each one of them will excel at what it was born for.

Indeed, but without a controlled input you cannot determine what causes the differences you're seeing.

It does. You have now identified that you are usually faster over one section on one bike than on another one. You cannot, however, determine why you are faster on one bike over the other. It could be that the fit allows you to generate more power, or maybe it puts you into a more aerodynamic position. Maybe it has better drivetrain efficiency, or it is lighter. Or maybe you get a tailwind more often on one than on the other, or you have a bigger breakfast when you ride one of them. Maybe even a bit of everything.

It would matter if he planned to invest on upgrades to make his ride faster. In that case knowing what the 'weak link' is so to speak would be crucial.