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20130920 8:39 AM 
Veteran 821 Omaha, NE  Subject: wattage gain needed to go from 20 to 22 mph I know this is a broad question with so many variables, wind, course, position etc. But given a mostly flat course with rolling hills and very low wind, average to slightly better than average position and a very clean bike, what type of wattage gain would I need? Ok shoot me now so many variables lol. I don't have a powermeter, but I do have a NAshbar wattmaster trainer. I don't know how accurrate the nashbar computer is compared to a powermeter out on the road, but from my experience I do know it is accurate. I'm going to be using that for my training and running Jorge's program a few times and was just wondering what type of gains I might need to accomplish the above. My Training LogMy Race Log 

20130920 8:44 AM in reply to: 0 
Extreme Veteran 635 Ajo  Subject: RE: wattage gain needed to go from 20 to 22 mph Yep, a lot of factors, you didn't say over what distance? Sprint, Oly, HIM, IM??? but depending upon your cda... you're going to need 220 to 240 watts average. I know of smaller folks with super aero positions that can get 22 mph on about 185 to 190 watts, but the avg. Joe is going to need the above mentioned range. In order to achieve that you're going to need a 265 to 310 depending upon which race distance you're doing. Here is a good link that I use a lot for experimentation: http://www.cyclingpowerlab.com/cyclingpoweroutput.aspx I also read, but don't have a link, but to go just from 20 to 22, only a 10% increase in speed, requires a 25 to 30% increase in power, to go from 22 to 24 requires another increase of 40% from the previous level.... my 22 mph wattage is around 225, but my 25 mph wattage is around 300, to go 26 (a measely 1 mph extra) it is around 350.. get the picture, it's exponential. Road surfaces have a lot to do with these numbers, the crr... tires, wheels and contact area, good or bad roads... I did a TT last sunday, got 59:30 and required 314 watts avg. and 320 np... but the roads were rough chipseal with dents, holes and ripples... when I went over a concrete bridge the speed increase by 1 mph, then after the bridge back to the chipseal and like riding through rough sand. The road surface meant a lower avg. speed by about 1/2 mph. A screen shot of my power file: with the wind factor  my effort equates to 26.2 mph, so it was always against the wind like there was a 1.1 mph wind at all times. As for the power numbers from the trainer, just do an FTP test on it and use them for training... don't rack your brain over whether they're the same as the road, most likely they're not... my FTP on my trainer, a Cyclops Fluid Pro, is around 265... my outdoor watts are 315, so you'll go crazy trying to make them equal. Have fun!! Edited by tomspharmacy 20130920 9:09 AM (Untitled.jpg) Attachments  Untitled.jpg (136KB  7 downloads) My Race Log 
20130920 9:59 AM in reply to: #4859947 
Subject: RE: wattage gain needed to go from 20 to 22 mph Agree in general with the above except that the power required to go a certain speeed does not depend on race distance. The amount of fitness required to hold that power level throughout depends on distance or actually time, but the actual power level is the same all else being equal.My Race Log 
20130920 10:10 AM in reply to: Jason N 
Extreme Veteran 635 Ajo  Subject: RE: wattage gain needed to go from 20 to 22 mph Originally posted by Jason N Agree in general with the above except that the power required to go a certain speeed does not depend on race distance. The amount of fitness required to hold that power level throughout depends on distance or actually time, but the actual power level is the same all else being equal. Yes, I didn't complete a thought... I meant to mean: the range of 60 minute FTP required for different distances... to go 22 mph avg. over an IM will require about a 300 FTP, b/c you're riding at about 70 to 75% power, whereas a Sprint distance, only an FTP of 250 is required since the effort is at 90 to 95% FTP. My Race Log 
20130920 11:04 AM in reply to: cstoulil 
Pro 6421 Melbourne FL  Subject: RE: wattage gain needed to go from 20 to 22 mph Originally posted by cstoulil I know this is a broad question with so many variables, wind, course, position etc. But given a mostly flat course with rolling hills and very low wind, average to slightly better than average position and a very clean bike, what type of wattage gain would I need? Ok shoot me now so many variables lol. I don't have a powermeter, but I do have a NAshbar wattmaster trainer. I don't know how accurrate the nashbar computer is compared to a powermeter out on the road, but from my experience I do know it is accurate. I'm going to be using that for my training and running Jorge's program a few times and was just wondering what type of gains I might need to accomplish the above. The others have said it well regarding the general wattage required.In my experience a few years back I came off a winter of HM training I went from lowmid 20's to mid 22's in two local Sprints focusing training around Jorge's training plan using virtual power on the trainer and a long weekend ride. A year later did the training plan once in entirety and a few weeks later the last 8 weeks again I won my AG in a local sprint with a 23.4 mph average. You have to consider the tires in this too, the rolling resistance wattage gains if coming from a "bad" tire set to something like GP4000s+latex is pretty significant. My Training LogMy Race Log 
20130920 12:47 PM in reply to: cstoulil 
Elite 5143 Cleveland  Subject: RE: wattage gain needed to go from 20 to 22 mph 

20130920 1:58 PM in reply to: tomspharmacy 
Subject: RE: wattage gain needed to go from 20 to 22 mph Originally posted by tomspharmacy Originally posted by Jason N Agree in general with the above except that the power required to go a certain speeed does not depend on race distance. The amount of fitness required to hold that power level throughout depends on distance or actually time, but the actual power level is the same all else being equal. Yes, I didn't complete a thought... I meant to mean: the range of 60 minute FTP required for different distances... to go 22 mph avg. over an IM will require about a 300 FTP, b/c you're riding at about 70 to 75% power, whereas a Sprint distance, only an FTP of 250 is required since the effort is at 90 to 95% FTP. Yeah, I knew what you were getting at, but just wanted to clarify...which you just did better than I. My Race Log 
20130920 2:33 PM in reply to: 0 
Extreme Veteran 635 Ajo  Subject: RE: wattage gain needed to go from 20 to 22 mph Originally posted by cgregg
Here, plug in the pertinent variables and play around.
I used to use that calculator but have found the previous one far more adjustable and accurate. We don't know the assumptions of the bikecalculator setup...it always shows faster than I actually have ever gone by just using my weight as the input. I'd also recommend these links too: 1. http://www.cyclingpowerlab.com/PopularEventModels.aspx 2. http://www.cyclingpowerlab.com/PowerSpeedScenarios.aspx 3. http://www.cyclingpowerlab.com/TriathlonBikePace.aspx 4. http://www.cyclingpowerlab.com/ComponentAerodynamics.aspx 5. http://www.cyclingpowerlab.com/CyclingAerodynamics.aspx To show a few... what's interesting in link 4 is that you can play with different equipment and see theoretical time savings. Edited by tomspharmacy 20130920 2:36 PM My Race Log 
20130920 2:35 PM in reply to: tomspharmacy 
over a barrier  Subject: RE: wattage gain needed to go from 20 to 22 mph 
20130924 3:44 PM in reply to: cstoulil 
New user 8  Subject: RE: wattage gain needed to go from 20 to 22 mph Here is a good site...http://www.kreuzotter.de/english/espeed.htm It says that based on someone 180 pound, 20mph is 162 watts and 22mph is 209 watts, so, an increase of 47 watts. 
20130924 4:26 PM in reply to: cstoulil 
Champion 7082 Fayetteville  Subject: RE: wattage gain needed to go from 20 to 22 mph Watts? Hard to say, but to move forward, you have to overcome: Rolling Resistance (assume a linear change with velocity, because you cover greater distance per unit of time) Drivetrain Friction (similar linear change with velocity) Wind Resistance (which varies with velocity squared) So to increase from 20 to 22 mph (10% increase in velocity), you need to overcome 21% greater wind resistance and 10% greater rolling and drivetrain resistance. . If you assume 10% of your power overcomes drivetrain resistance and 20% rolling resistance, 70% is allocated to wind resistance. (0.1*0.1 + 0.1*0.2 + 0.21*0.7 = 0.177) 17.7% more watts than it takes you at 20 mph. My Training LogMy Race Log 

20130924 5:26 PM in reply to: JJFlyer 
Veteran 193 Havertown, PA  Subject: RE: wattage gain needed to go from 20 to 22 mph Originally posted by JJFlyer Here is a good site...http://www.kreuzotter.de/english/espeed.htm It says that based on someone 180 pound, 20mph is 162 watts and 22mph is 209 watts, so, an increase of 47 watts. cool calculator. thanks for posting. i entered my #s from a race on saturday and it was pretty much spot on! Some N=1 data for the OP, it took me 234w NP to avg 22mph over 112 miles on a pancake flat course at sea level which was at .695 IF...but i am a bit of a a mutant @ 6'5" 220lbs. My buddy weighs 25lbs less and did the same ride at 20mph on 189w NP. we were both on P2s with aero helmets and race wheels. not sure if that's helpful, but it was in your parameters, so i thought i would share.My Race Log 
20130924 9:35 PM in reply to: gergzos 
287  Subject: RE: wattage gain needed to go from 20 to 22 mph Originally posted by gergzos Originally posted by JJFlyer Here is a good site...http://www.kreuzotter.de/english/espeed.htm It says that based on someone 180 pound, 20mph is 162 watts and 22mph is 209 watts, so, an increase of 47 watts. cool calculator. thanks for posting. i entered my #s from a race on saturday and it was pretty much spot on! Some N=1 data for the OP, it took me 234w NP to avg 22mph over 112 miles on a pancake flat course at sea level which was at .695 IF...but i am a bit of a a mutant @ 6'5" 220lbs. My buddy weighs 25lbs less and did the same ride at 20mph on 189w NP. we were both on P2s with aero helmets and race wheels. not sure if that's helpful, but it was in your parameters, so i thought i would share. Improved body position on your bikeaerodynamicscan altered this equation as can weight loss. At 6'5" it is likely you present a larger than normal frontal area on your bicycle than most other competitors and your watts are likely going to have to be higher to ride at the same speed. At 220 lbs, climbing hills is going to require higher watts than that lightweight goat in your age group. Good luck.My Race Log 
20130925 7:52 AM in reply to: 0 
Veteran 821 Omaha, NE  Subject: RE: wattage gain needed to go from 20 to 22 mph Thanks for all the replies guys. Distance I was wanting to see the gains at was for sprint distance. I know racing towards a speed number in mph isn't ideal because every day even the same course will very. I was targeting this towards a local race next year. It's a fun small race, but also the only race my family ever gets to see me race. Being a smaller race, based on the results from the last 4 years, 22 mph would put me FOP for sure. As far as the bike, I've done a pretty good job with it on a budget, I've got about $1550 or so into no counting the wheels/tires. I have a Flo 60/90 or disc combo and GP4's. I also have latex tubes, but I've yet to actually race with the tubes. For my front end I modified an Ozero base bar to bring the cables out the back. I know I could still work on my cda. Losing about 20 lbs would help with that and probably a better position, I only have about 7.5cm of drop right now, but I think I have a decent position. I just have to work on turtling more, which isn't a problem for a short sprint, but I get lazy for HIM lol. Best speeds to date. 20.6 on a long sprint course (19 miles) 18.66 on a HIM 17.23 on the only IM I've done. Edited by cstoulil 20130925 7:56 AM (front.jpg) (side.jpg) Attachments  front.jpg (55KB  8 downloads) side.jpg (78KB  8 downloads) My Training LogMy Race Log 
First 20 mph ride, errrrrrr maybe? Pages: 1 2  
The 20 mph barrier Pages: 1 2  
 

 

 

