WVU_Engineer

I watched parts of the tour de france the past couple days on TV for the first time and I couldn't believe the speed these guys were hitting.

Has me thinking, I am 6'5" and quite a big parachute, add in my 290 lbs, and a 40ish lb bike with 26 inch tires and over an hour I average about 11 mph with a top speed of about 20 mph. I really don't car about my speed since I bike just for the exercise but am wondering what my biggest hold backs are for more speed. When I hit 20 mph I can really feel the parachute effect pushing back on me.

FullGas

as an engineer, you're asking this as a serious question...?

WVU_Engineer

I am asking for peoples experience, I ride my bike around the neighborhood.

There isn't exactly an equation that takes these variables into account so I can see which one is the greatest contribution.

Serious question here, why be an ass?

CliffordK

Follow fast riders?

Many heavier riders can achieve good speeds on the flats, only to be snowed under on the hills.

However, consider body position. Road bike built for speed. Lightweight wheels. Aero here and there. Plus drop bars that position the body much lower. And not just hanging onto the bars, but often with the elbows bent and the rider as low as possible.

And those riders are STRONG.

Drafting helps a lot. I'm not sure how frequently riders in a paceline line rotate, but it means they also have the ability to recuperate quickly. So, say I ride 25 MPH for a half mile, it might take me quite some time to get my legs back. For the "pros", they do the 25 MPH pull, fall to the back of the paceline, and continue to pedal hard while drafting, and are recuperated by the time their next pull comes along.

Willbird

There are many calculators online and as aps for calculating the energy required to move a bike and rider a certain speed over a distance or course. One for IOS is called "bike calculator". It has changeable factors like bike type, ride position, rider weight. Steady state on flat ground rider weight is mostly insignificant.

Strava attempts to come up with a wattage output and or energy used figure. Garmin units do too. Strava ignores heart rate in it's calculations as far as I can tell, Strava logs it but must not factor it into calculations. It will show after a ride how much time you spent in each wattage output range.

But garmin uses heart rate. The battery in my wahoo tickr Heart Rate Moniter was dying on me yesterday....garmin was being told my heart rate was 45 beats per minute at 16mph....so garmin decided I only burned 313 calories to cover 30 miles. Strava decided 1000 calories.

Primitive Don

I'm more or less a novice, but I do register higher average speeds on my steel road bike with 700c wheels smoothish tires than I do on my heavier aluminum MTB with 26 wheels with small knobby tires. I am 250, and the weight difference between the bikes is only about 10 pounds, so it *shouldn't* make that much of a difference, but I suspect the larger diameter of the 700c wheels together with the smaller weight of the bikes makes a difference in the speeds I can manage. Also, when I bought newer wheelsets with better hubs with smoother bearings, I felt like that translated into lower resistance and faster speeds. My unscientific 2 cents.

Of course becoming more fit really helped me rack up higher average speeds as well. Once I started racking up higher speeds on Strava, then a more fit cyclist/racer friend took notice and invited me along for a ride. Of course I still had a bit of trouble keeping up.

jsigone

those riders also sacrifice body comfort for aero position so AT speed, they use less watts.

They also ride 120miles day after day over mountains or 50mph sprints.

Enjoyable to watch though.

brawlo

The 2 critical answers are your tyres and your body position. BTW I'm also 6'5" and not a huge amount lighter than yourself ~ I was heavier when I started.

Back when I rediscovered cycling I was on a Giant Sedona comfort mtb thing. The tyres rolled reasonably well when the pressure was at their upper limit. I was at the local velodrome just pumping some hard laps one day when a girl was there training on her track bike. She was riding around and I thought I was awesome because I was keeping up with her. Then she asked me to ride up high (it's not a steeply banked velo) while she did some efforts. Wow, that was the moment I knew I wanted a road bike! I remember it vividly!

I now (9yrs later) ride track and road bikes and dabble a little in MTB. I didn't sell the Sedona until last year as I kept it for pootling around with the kids. Every time I got on that bike with it's fat 26" tyres, even with higher pressures, it was like riding with the brakes on compared to the road bike.

So the tyres, higher road tyre pressures, and slightly larger wheel diameter will help you to roll along a lot easier. From there, going fast is about a mix of body position and power. Getting more aero with your body means you need less power to maintain speed as you're pushing less air. I can easily ride 3-4km/h faster in the drops on my road bike compared to on the hoods, even though it's not a big drop in height. If I bend my arms and get even lower, then I can go even faster!

On another note, are the dynamics of bunch riding. Despite the speeds that the bunches are doing, it is really only those riders at the front and the rear of the peloton that are working hard. When you ride within a large bunch like they do, it doesn't require a huge effort to cruise along, even if the speeds are high. The riders at the front are breaking the wind, while the riders at the rear are the victims of the slingshot effect.

deapee

Well you see, to propel yourself in a straight line, the main limiting factor is wind resistance.
When climbing a hill, however the main limiting factor will be gravity.

You look at your size as a disadvantage. But truthfully, it's an advantage on the flats, assuming your body's flexibility allows you to get into somewhat of an aerodynamic position. To assume that a person who is 5'8 and 155 pounds can generate anywhere near the wattage you can would be a poor assumption. Theoretically you should leave smaller riders on the flats and they should be able to pass you going up hills (theoretically -- obviously different people are different). Watts per killogram (that is the power you can output relative to your combined weight) affects one's climbing speed...obviously the amount of the grade is going to come into play here as different grades will result in different gravitational pulls that the rider is overcoming.

PS -- 20 mph isn't some magical number where something phenomenal occurs. Do you think people from other countries are like "man, at 32.1869 KPH exactly, I can really feel the wind pushing me back." 20 MPH is a mental hurdle. There is a non-linear curve involved, but nothing extraordinary occurs at exactly 32.1869 KPH...

Willbird

It would be interesting to setup a bicycle like what the op described and handicap each rider for weight and aerodynamics, then them ride a TT. The pro riders would still kick butt, but the data would be interesting no doubt.

andr0id

No they don't. You can't ride for 6 hours a day, 7 days a week being uncomfortable.

You can ride a TT bike for 50 minutes and give up some comfort, but I guarantee you every one of those guys are more comfortable on their road bikes (as far as fit) than you are.

Willbird

https://www.bicycling.com/training/2015-tour-de-france/you-versus-tour-de-france-pro

This sums it up pretty good, watts equals forward velocity :-).

jsigone

anyone would feel more comfy on a roadie vs a TT bike any day of the week

10 Wheels

Start by putting in 20,000 miles a year like the Pros do.
Then come back with your comment.

WVU_Engineer

Understand, that is just roughly the speed I can get up to on flat, and when I stop pedaling I can really feel myself decelerate. Much past 20 mph I start to feel uncomfortable as in I know I won't be able to stop very quickly if a runner crosses my path inadvertently, I took one out years ago that wasn't paying attention.

WVU_Engineer

My main reason for the original post was that to me it was completely inconceivable to hit these speeds on a bicycle, this is the first time I ever watched a road bike race.

CliffordK

I disagree.

I think it is a "magical number" and essentially the dividing line between a little effort and a lot of effort.

In metric, one could use 30 or 32 KPH, and it is still a lot of effort to maintain it.

Anyway, I do think it is a good goal (from which you can vary your goal by a few MPH). Maintain 20 MPH for a few miles, so try 21 MPH?

30 MPH is also one of those "magical numbers" where it can take a LOT of effort to reach and maintain 30 MPH on the flat without wind or drafting. And, you can use your favorite Metric equivalent, 48 or 50 kph. I can pretty easily reach 27 or 28 MPH, but that extra few MPH to get to 30 is tough.

Of course, it also depends on the bike. I'm finally getting to where I can maintain 20 MPH for about 10 miles, but doing that on a MTB with a 40T chainring would sink me.

deapee

Right, of course because when you hit your personal limit on an exponential curve (even a linear curve), you're going to feel like eeking out that extra 2-3 is tough.

Whether that number is 17, 22, 28, or 30. There's just nothing special that occurs at 20 mph in regards to the exponential function in relation to speed/power/wind resistance.

Jseis 

Download the app or enter data and play around with the calculator below, particularly with % slope... Very informative and gives a sense of what a pro watt output is.

Bike Calculator

Cosmic Hawk

Everyone seems to have ignored that these guys are riding 100 deep in a peloton. If you have ever ridden in a peloton, you will understand how a group that large goes faster than a single rider. that's why they ride in a peloton. They understand that they have to work together to get to the finish line.

You also forget that, sorry to say, but these guys are pretty much guaranteed to be on EPO, testosterone, etc etc etc.. You don't have to believe it, but people believe the Olympics are clean, too. You will never go as fast as them because they are physical freaks who reach their maximum level and then take exogenous drugs that make them even faster.

They also have power to weight ratio over you.. Wanna ride faster? be 160 pounds and maintain your power.. you'll be super fast. I averaged 24 MPH over 36 miles race last week at 215 pounds and guess what, I came in 22nd place. there are so many people in the world, you have to understand that some of them will be able to put out freak power numbers , and that out of those, many will add exogenous help.

Just my two cents. Ride your speed, have fun, and eventually, you'll get faster. reach for the distance or climbing goals and leave yourself impressed.

Willbird

I just watched YouTube highlights of stage 1 or 2 2016 the other day, the solo breakaway rider who eventually got reeled in was not riding 100 deep :-).

Cosmic Hawk

I watched it live. I was rooting for him but pelotons are faster as I said and they caught him. He got away during a lazy spot in the peloton ride. The peloton was almost riding in protest to the danger the organizers were creating with the course layouts. All thosenGC contenders crashing 2 days in a row doesn't sit well with them. You have to remember, a lot of people's some job on the tour is to make sure their team's contender finishes and finishes well.

Tdf is way more of a Chess match than it is a bike race to me.

Willbird

I have never watched any of it before so all new really :-). But yea there was really no doubt they would reel him in eventually :-)

WVU_Engineer

To shift topic slightly, I was amazed at the number of people that threw their hands out at the bikers or some blow up marketing toy. I saw one guy even throw his hand in the face of a rider.

squirtdad

to op, bike makes a big difference... as example, with similar tires on both bikes (700x28 and 700x25)

on this bike with it's upright position I am typically 1-2 mph slower for same effort (at under 15 mph difference gets greater as I go faster



than I am on this bike, with more aerodynamic position and improved leg biomechanics