Scantlings

http://www.sciencealert.com/this-bike-j ... vel-speeds
Totally blows me away the amount of work and engineering that went into this bike. Enjoy.

Fascinating piece of engineering. I would be very curious to know what the thinking was for choosing a somewhat 'pointy' nose. Nothing that I have seen says a point on the front does anything but slow you down until you get up around mach .9 or so. Occasionally, an airplane with some sort of equipment (guns, radar, antenna etc.) in the nose will have a legitimate reason for a point on the front. Otherwise it is just styling.

Steve

I wonder if the internal workings dictated the frontal shape? Your 10 lbs of shit going into a 5 lb bag quandary.

This is amazing!!

I am astounded at the amount of surface area. The shape (no point on the front) should all be about attached laminar flow, so far as I know. The next optimization is to reduce the total surface area, which it looks like these guys haven't done much of. But what do I know? I'm a hack compared to these folks.

Another thought, once areo drag has been reduced this much, other stuff is probably starting to matter. I would hope they have solid wheels, as areo drag on spokes is a big deal on a bike going this fast. Also solid tires - or a lot of airpressure. Then there's the lose from the chain. I just took a look at a bike that had a beautiful two gear system which was reported as having about 1/8 the drag of a bike chain on sprockets. Of course, it was the ultimate "fixie".

BeauV wrote:This is amazing!!

I am astounded at the amount of surface area. The shape (no point on the front) should all be about attached laminar flow, so far as I know. The next optimization is to reduce the total surface area, which it looks like these guys haven't done much of. But what do I know? I'm a hack compared to these folks.

Another thought, once areo drag has been reduced this much, other stuff is probably starting to matter. I would hope they have solid wheels, as areo drag on spokes is a big deal on a bike going this fast. Also solid tires - or a lot of airpressure. Then there's the lose from the chain. I just took a look at a bike that had a beautiful two gear system which was reported as having about 1/8 the drag of a bike chain on sprockets. Of course, it was the ultimate "fixie".

Pretty interesting short video. They go over a lot of the details and claim that this version is some 42% smaller than the previous one and discuss the laminar flow requirements. Even show a map.

BeauV wrote:This is amazing!!

I am astounded at the amount of surface area. The shape (no point on the front) should all be about attached laminar flow, so far as I know. The next optimization is to reduce the total surface area, which it looks like these guys haven't done much of. But what do I know? I'm a hack compared to these folks.

Another thought, once areo drag has been reduced this much, other stuff is probably starting to matter. I would hope they have solid wheels, as areo drag on spokes is a big deal on a bike going this fast. Also solid tires - or a lot of airpressure. Then there's the lose from the chain. I just took a look at a bike that had a beautiful two gear system which was reported as having about 1/8 the drag of a bike chain on sprockets. Of course, it was the ultimate "fixie".

They say they're using "custom" tubulars and I assume they're condom-thin, but not all that narrow or high pressure. Wider, lower-pressure, tires are faster because they deform more easily when they roll. On "normal" bikes, the tradeoffs are in weight and forward surface. From what I can see, the tires are around 25 mm, which is what I ride most of the time. From what's on the Web, the wheels appear to be fairly normal-looking carbon rims with spokes, spinning inside vented housings, which cover them right down to the ground.

There must be a really interesting trade-off between running at 4,500' altitude at Battle Mountain vs having more air for the person turning the peddles at sea level.

258 watts for 100kph? And they only measure the last 200 meters?

Want to break that record?

Calling the Swiss Time Machine, please report to Battle Mountain.

Fabian would clobber that record.

And so would Mark, or Peter, or Tony, or any of the real powerhouse pro riders.

kimbottles wrote:258 watts for 100kph? And they only measure the last 200 meters?

Want to break that record?

Calling the Swiss Time Machine, please report to Battle Mountain.

Fabian would clobber that record.

And so would Mark, or Peter, or Tony, or any of the real powerhouse pro riders.

I didn't see that. I can put that out for a few minutes and I weigh less than that guy. For those not familiar with this measure the big boys can put out 10-15 W/Kg for a few minutes and 6 all the way up big mountains. Appears any journeyman pro would blow that record away.

Orestes Munn wrote:

kimbottles wrote:258 watts for 100kph? And they only measure the last 200 meters?

Want to break that record?

Calling the Swiss Time Machine, please report to Battle Mountain.

Fabian would clobber that record.

And so would Mark, or Peter, or Tony, or any of the real powerhouse pro riders.

I didn't see that. I can put that out for a few minutes and I weigh less than that guy. For those not familiar with this measure the big boys can put out 10-15 W/Kg for a few minutes and 6 all the way up big mountains. Appears any journeyman pro would blow that record away.

I read somewhere that Super Mario could hit 1600 watts for a few seconds!
300-400 watts during a climb is not unusual for the great climbers.

Mark does not weigh much and he is very compact, Tony likewise.

And then there is Sir Chris Hoy. I bet he can produce a ton of watts for 200 meters, even now as a retired guy.

kimbottles wrote:

Orestes Munn wrote:

kimbottles wrote:258 watts for 100kph? And they only measure the last 200 meters?

Want to break that record?

Calling the Swiss Time Machine, please report to Battle Mountain.

Fabian would clobber that record.

And so would Mark, or Peter, or Tony, or any of the real powerhouse pro riders.

I didn't see that. I can put that out for a few minutes and I weigh less than that guy. For those not familiar with this measure the big boys can put out 10-15 W/Kg for a few minutes and 6 all the way up big mountains. Appears any journeyman pro would blow that record away.

I read somewhere that Super Mario could hit 1600 watts for a few seconds!
300-400 watts during a climb is not unusual for the great climbers.

Mark does not weigh much and he is very compact, Tony likewise.

And then there is Sir Chris Hoy. I bet he can produce a ton of watts for 200 meters, even now as a retired guy.

Guys, these are a bunch of engineers. They don't have the budget to get a guy like Zabell (in his prime) or Canvendish. This only shows there is a LOT more speed that one can capture.

BeauV wrote:

kimbottles wrote:

Orestes Munn wrote:

kimbottles wrote:258 watts for 100kph? And they only measure the last 200 meters?

Want to break that record?

Calling the Swiss Time Machine, please report to Battle Mountain.

Fabian would clobber that record.

And so would Mark, or Peter, or Tony, or any of the real powerhouse pro riders.

I didn't see that. I can put that out for a few minutes and I weigh less than that guy. For those not familiar with this measure the big boys can put out 10-15 W/Kg for a few minutes and 6 all the way up big mountains. Appears any journeyman pro would blow that record away.

I read somewhere that Super Mario could hit 1600 watts for a few seconds!
300-400 watts during a climb is not unusual for the great climbers.

Mark does not weigh much and he is very compact, Tony likewise.

And then there is Sir Chris Hoy. I bet he can produce a ton of watts for 200 meters, even now as a retired guy.

Guys, these are a bunch of engineers. They don't have the budget to get a guy like Zabell (in his prime) or Canvendish. This only shows there is a LOT more speed that one can capture.

Whoaaaaaaaa, what a minute. The record is 144.17 kph not 100. And since the wind pressure increases with the square of the speed, 144.17 / 100 = 1.4417 and 1.4417 X 1.4417 = 2.08 and 2.08 X 258 watts = 536 watts.

Perhaps they already have a strong peddler?

Steve

All I know is that the shape is exquisitely suppositorial.

Panope wrote:

BeauV wrote:

kimbottles wrote:

Orestes Munn wrote:

kimbottles wrote:258 watts for 100kph? And they only measure the last 200 meters?

Want to break that record?

Calling the Swiss Time Machine, please report to Battle Mountain.

Fabian would clobber that record.

And so would Mark, or Peter, or Tony, or any of the real powerhouse pro riders.

I didn't see that. I can put that out for a few minutes and I weigh less than that guy. For those not familiar with this measure the big boys can put out 10-15 W/Kg for a few minutes and 6 all the way up big mountains. Appears any journeyman pro would blow that record away.

I read somewhere that Super Mario could hit 1600 watts for a few seconds!
300-400 watts during a climb is not unusual for the great climbers.

Mark does not weigh much and he is very compact, Tony likewise.

And then there is Sir Chris Hoy. I bet he can produce a ton of watts for 200 meters, even now as a retired guy.

Guys, these are a bunch of engineers. They don't have the budget to get a guy like Zabell (in his prime) or Canvendish. This only shows there is a LOT more speed that one can capture.

Whoaaaaaaaa, what a minute. The record is 144.17 kph not 100. And since the wind pressure increases with the square of the speed, 144.17 / 100 = 1.4417 and 1.4417 X 1.4417 = 2.08 and 2.08 X 258 watts = 536 watts.

Perhaps they already have a strong peddler?

Steve

I really doubt they have a rider as strong as Mark Cavendish. I bet Cav hits a lot more than 536 watts for the last 200 meters of one of his Tour de France sprint finishes. (Hell, I can hit more than 500 watts, I should check and see how long I can hold it. Maybe not 200 meters, but I am 68. Cav is less than half my age. And he is a sprinter, I was a time trial specialist for distances measured in miles, not meters.)

That 200 meters at speed lasts for about 5 seconds +/-, l wonder how long you have to hold it to build to the speed necessary. You clearly ramp it up and want to hit max for that last 5 secs or so.......

(My legs are starting to cramp just thinking about this!)

Panope wrote:

BeauV wrote:

kimbottles wrote:

Orestes Munn wrote:

kimbottles wrote:258 watts for 100kph? And they only measure the last 200 meters?

Want to break that record?

Calling the Swiss Time Machine, please report to Battle Mountain.

Fabian would clobber that record.

And so would Mark, or Peter, or Tony, or any of the real powerhouse pro riders.

I didn't see that. I can put that out for a few minutes and I weigh less than that guy. For those not familiar with this measure the big boys can put out 10-15 W/Kg for a few minutes and 6 all the way up big mountains. Appears any journeyman pro would blow that record away.

I read somewhere that Super Mario could hit 1600 watts for a few seconds!
300-400 watts during a climb is not unusual for the great climbers.

Mark does not weigh much and he is very compact, Tony likewise.

And then there is Sir Chris Hoy. I bet he can produce a ton of watts for 200 meters, even now as a retired guy.

Guys, these are a bunch of engineers. They don't have the budget to get a guy like Zabell (in his prime) or Canvendish. This only shows there is a LOT more speed that one can capture.

Whoaaaaaaaa, what a minute. The record is 144.17 kph not 100. And since the wind pressure increases with the square of the speed, 144.17 / 100 = 1.4417 and 1.4417 X 1.4417 = 2.08 and 2.08 X 258 watts = 536 watts.

Perhaps they already have a strong peddler?

Steve

Reichert, the rider, planned to go 350 W for the first 4 min and 600 for the last min on a previous record run, and ended up at 500. If he weighs 75 kg, he's a very strong amateur.

I hope this does not bore you guys, but I find this stuff very interesting. Feel free to skip this if the Human Powered Land Speed Record doesn't interest you.

Ok, because I once was a pretty good bicycle racer (ABLofA Class A Senior 1966 thru 1974) and I happen to have and use a Computrainer on a regular basis (http://www.racermateinc.com/computrainer/) I decided to check out this 536 watts for 5 second thing.

I am not nearly as smart or as talented as Steve, so I should have invited him down to monitor the test, but I didn't so we will just have to take the information I gathered this morning and mull it over.

I am not nearly as fit now as I have been in the past, but I am still pretty fit, I ride 3-6 times a week and I ride fairly fast. I am 6' and 190 pounds. I raced at 168 pounds many years ago and last time I was mega fit I was 176 pounds (in 2005).

I ride hill repeats on the Computrainer several times a month. I ride eight repeats of 500 meters at about 350-450 watts each with about 5 minute 100 watt rest periods in between. These watts for 500 meters are hard, but that is the whole idea of interval training. I remain seated during the climb almost always (with maybe a few out of the saddle efforts toward the top of the last interval or two.)

So this morning I warmed up for 10 minutes at 150 watts and then calibrated the Computrainer per their standard instructions.

I then rode a 15 mile flat effort with eight very hard intervals spaced throughout. The goal was to ramp up through the watts to arrive at 536 watts and hold it for 5 seconds. I kind of succeeded the first 4 times, holding somewhere around 530 watts (it is very hard to remain steady at that effort, so I was bouncing around +/- 530 or so for the 5 seconds.

I was able to hit the 530ish the last 4 tries, but faded down to around 475-500 watts by the end of the 5 seconds. My max wattage was 582 which I hit as a test on repeat #7 by getting out of the saddle, all other efforts were seated at about 130-140 rpm.

Now remember I was a time trialist, not a sprinter. I rode 10-25 mile individual time trials and the 100km 4 man team time trial. I also rode 60-125 mile road races and was a reasonable good climber. I rode the Madison two man event on the track, I was the stayer and was partnered with a sprinter (Jeff Spencer, Former Olympian.) I have trained and ridden with ProTour riders and many Olympians. (Came kinda close in the 1968 trials, but did not make the road racing team.)

I can ride for a very long time at 200 watts and for many miles at 250-300 watts. I am an endurance athlete not a max speed performer (interestingly my max HR during the ride this morning was only 145 which indicates my leg strength is not keeping up with my CV system. I usually hit 155-160 HR towards the end of an hour long motor pace at around 28 mph. My strength was always my CV system.)

So I think this indicates that if they put Cav (or a number of other ProTour sprinters) in that streamliner theywould demolish that 89mph record (if they could adapt to the recumbent position. I have a recumbent lowracer (Velokraft VK-2) and it does take some getting use to. Cav finishes off his sprints out of the saddle which can't be done in a recumbent, so there is that question.)

I am pretty confident that I could do better than 60 mph in that streamliner at my current age of 68, especially if I trained for 6-8 weeks beforehand and if I could fit my oversized body inside it. (Cav is much smaller than I am.)

Maybe we can crowd fund enough $ to get a ProTour rider in that streamliner.

I would crowd fund Kim to ride in that stream liner. Now what incentive could we dangle in front of that camera to motivate Kim. I just rode my bike and never paid attention to the math. You gents are speed freaks. Knowledgable ones at that.

Kim, thanks for running that test. Interesting data. I rode a friend's lay-down bike for a bit. He had shoulder braces that allowed me to push harder on the peddles than I could be simply standing up. As you know, when a good rider is standing they are pulling on the bars as well as using both legs against each other. I found the shoulder bracing to be much more effective than standing up on a normal bike. BV

OK, here is some REAL information:

My friend Kiel Reijnen who rides for treksegafredo in the ProTour (he just finished the Vuelta a Espana, one of the three Grand Tours) is visiting his Dad here on Bainbridge Island right now and going around and destroying all of the local records.

http://www.treksegafredo.com/team/riders/kiel-reijnen

His Chilly Hilly course average power was 351 watts FOR AN HOUR AND TWENTY MINUTES. And he is much smaller than I am. (Chilly Hilly is one of the classic rides in the USA and as the name says it is VERY Hilly.)

Put him in that egg (he would fit easy) and he goes well past 90mph! (He has a very good sprint having won a number of field sprints in the ProTour. Bet he can put out 700-1000 watts for a 200 meter sprint.)

(The previous CH record was 1:50!! )

Really interesting info! But, your pal is a Boulderite. So he's used to living at altitude!! He must feel like a GOD at sea level.

(I'm guessing he is Dutch, or his pappy was.)