I think you missed the number one free upgrade. Optimize your position on the bike, and develop the core and arm'shoulder strength to hold it. Obviously, you can't know precisely what that is without a wind tunnel, but getting your back flat and air off your chest ought to be at the top of the list.
I appreciate the tire pressure calculator -- I wonder how old classic tublar tires (sew-up's) stack up against newer tubeless -- in the early 80's, we used to ride Clement Criterium and Clement Paris-Roubaix Seta's (silk). Looking back with the more recent knowledge about rolling resistance, it seems the fatter Paris-Roubaix tires which we ran at lower pressures may have been the faster ones. We would run the Criterium Setas at 110-120PSI. Maybe 100PSI for the Paris-Roubaix's.
Josh can you please explain why is it that shaving saves watts, yet aero socks reduce drag by adding micro vortex around the calf, why doesn't hair accomplish the same thing? Can you make a video explaining that?
You're going to end up looking like a NCAA or Olympic competitive swimmer! I thought the original reason for bicycle racers shaving their legs was to make changing the gauss bandages easier after you got road rash from a sliding crash. Especially important with Italian racers with Gorilla Legs!
Love your vids Josh. I ran into this gem but wonder what happened to the tire pressure calculator (page not found)? Is there another I can access that info?
Not sure if I could maintain 50kph for more than a minute however... Riding endurance events lasting 24hours or more can be beneficial if you're saving 10-20 watts for every minute riding over that distance or time.
While wattage savings are reduced at slower speeds, the time saving and calorie savings grow as the rider is on course for longer.. the beauty of these types of gains is that you can either go faster/farther on the same energy expenditure, or go the same speed/distance on less energy expenditure.
Excellent video as always, would it be possible to do a similar comparison with weight? Eg cleaning your chain has the same power saving as dropping X kg in the same conditions?
Have tried hot waxing the chain and with dry lube wax based lubricants. The chain runs noticeably smoother than with oil based. Neither wax seems to do as much to fight rust. Wax doesn't attract much dirt but eventually a cleaning would be beneficial. Wear metals must accumulate as well as a small amount of abrasive dust.I prefer not to use any acetone because of toxicity. Water will not dissolve either type wax unless it is hot. Others have said boiling water poured over a chain will remove wax. An ultrasonic cleaner if it could withstand that temperature might be good in that role. The manufacturer warns not to run it to long at a time or transducer life may be compromised. Could that statement be due to heat generation by the transducer, or could the heater element overheat the transducer? Wax melts below boiling point of water.
You want to use a low polar/non polar solvent like ethanol/methanol/isopropanol if you want something that somewhat disolves wax. Hot isopropanol/methylated spiritis(when I'm feeling cheap) is what I use the most to clean waxed chains to increase intervals between deep wax chain cleans. In terms of cleaning power for single solvent application, here are the solvents in ascending efficacy in cleaning wax: Water > Methanol > Ethanol(methalyted spirits is 90% ethanol + 10% methanol) > Isopropanol > Acetone > Ethyl acetate> Benzene > Carbon disulfide > Hexane
Thought experiment. I was thinking about 3D printing non structural forms to elongate the trailing edge of round tubes, eg seat or down tubes. Wouldn’t win a beauty contest. What do you think?
There is excellent research on this dating back to the 1930's.. this is called a Thwaites Flap and can reduce the Cd of a cylinder by up to 50% depending on reynolds number.. it can even be decent at some lower yaw angles! This worked well for the early Rossin pursuit bikes in the 80's and looked awesome before being later refined by Cinelli in the Laser - josh
SILCA Velo much appropriated, Josh. I will check checkout the studies and do a lit search on similar papers. I like the Silca RU-vid channel because it illustrates the concepts covered on the Marginal Gains Podcast. I think you and your MG pod team make the material fairly easy to conceptualize.
Yes! The easiest way to convert savings at the industry standard 50kph to your speed is to take the wattage savings and multiply by Snew^3/Soriginal^3 so in this case 10w X 30^6/50^3 = 2.16w
Another question... if using latex tubes a spare tube needs to be carried as they cannot be repaired like butyl. Does the weight of a spare tube negate the watts saved by using latex tubes?
I don't know about you, but I ALWAYS carry at least ONE spare (butyl) tube, AND 2 of the Park Tool little adhesive backed patch kits when I ride anywhere. I (very successfully, without much flatting, unlike DroneScene above) ride latex inner tubes all of the time, but if I flat one, it is a bit quicker/easier/less time spent on the side of the road being OCD about the install to just throw in a butyl until I get home and change back to a fresh, new latex tube. Since I do NOT have anyone to call to come pick me up (and I am not even too sure about AAA honoring their promise to get me home if I called them!), I don't care if it negates the gains of using latex tubes by carrying a spare of any material by 10 times, I will STILL use latex inner tubes for their response, 'suppleness', and yes, even self-motivating sound in a good, high TPI cotton casing 'open tubular' type clincher (like the better Vittoria Corsa series). NOT every joyous thing about riding a bike can be measured in a lab in wattage. 😉
Material. It's all about hysteresis, the deformation of the tyre over an imperfect road surface. Essentially, a latex tube returns to its original shape far more quickly than butyl.
Hi Josh, unfortunately I cant use your Inner Tubes. I have tried 5 from you plus 5 more from different companies and they all get flat on the first ride or just blow in the middle of the night while I am sleeping. My wheels are Enve 4.5 with GP4000 Tires. I though issue was the tire so I replaced for a brand new GP4000 and same result. Then I called enve, they though maybe the wheel tape was bad, we put a new one and same result! Lol. Is a mystery really lol
They can be very tricky to install and may not work on some tire/rim combinations as it might be impossible to get them installed without pinching.. we have some good video content on our channel about this, the latex is so stretchy that it can get caught or pinched by the bead during install leading to this type of instant failure right after the install.
SILCA Velo Yep, weird part the front wheel is fine, rear one fails within a day lol! As you said is probably the combination of wheel and tired used. Thanks for the rely :)
I shave my upper arms for vanity. :-) There's no way on this current Earth that I'm gettin' around with hairy bi's and tri's, or delts, for that matter
it's all about boundary layer thickness and location of flow separation..even more aero than shaved arms are the modern body suit materials with localized textures optimized for the specific flow over that area.. so think of aero socks, with the thin vertical ribs to trip the flow to turbulent.. same effect as dimples, but more tailored to the calf, similar materials are used in the upper arm sleeves of TT suits.. the challenge with wheels/tires is that they are spinning, so you have very little control over what part of the surface is in what type of flow at any given time.. dimples are a great solution for these conditions as they give you general roughness over a very broad range of possibilities.
If you have listened to Josh for any amount of time you'll know that he puts very little weight on weight. He thinks weight (on the bike especially) is really the last thing you want to think about when making yourself more efficient on the bike.
So does drawing on the anger you feel at the guy who got your teenage Mommy pregnant. And being a Sociopathic asshole on and off the bike to everyone who won’t go along with, or raises questions about, your career-long drug cheating. There is no way he would have ridden as strongly as he did without chemical enhancement. Floyd Landis is another example of cheating to make up for lack of true greatness.@@timtaylor9590
@@EdwardTBurke-pv3qr lol ok. Greatness always spawns from disaster. Lance was the best who ever did it in a pelaton full of dopers he was just better. Is he your ex boyfriend or something why you so butt hurt
