If you are looking to take your training to the next level then consider one of my online science based training plans available here: www.trainingpeaks.com/coach/dylanjohnsontraining#trainingplans
If wider tires have lower rolling resistance and assuming this does not apply to bicycle tires only, then that means putting wider tires in cars can actually improve efficiency?
@@sepg5084 as it was said in the video, there is a limit in both directions. As far as i know, car tyres are already very very wide as the are optimised for grip, not for rolling efficiency. Look at the electric car tyres where efficiency (= range) is critical, the are much thinner :)
Let me know if you liked this style of video and if I should include more guests in the future. There is a lot more from this conversation that I plan on releasing. Find your optimal tire pressure with the Silca Professional Tire Pressure Calculator: silca.cc/pages/sppc-form Find out which tires are faster or slower with BicycleRollingResistance.com: www.bicyclerollingresistance.com/
Hi Dylan, I very much enjoyed this style of video. I was hoping Josh/you would get into discussing the pros/cons of various tread types & tire manufacturers. I've been on nothing but Rene Herse tires for years -> Barlow Pass 38mm slicks which actually measure 43mm on my FSE 27mm internal width wheels... However, I've had my eye on some Vittoria tires as well. Thanks again for the great content!!
I got a new bike! I ran 25mm tires at 120 psi on my old bikes for many years. My new bike came with 32mm tires. I used a tire pressure calculator and I currently run them at 55/60. I don't think these tires roll faster, but they are much more comfortable on the chip seal road surfaces I ride around here. I'm old, so comfort is a priority.
Id say the big guys are actually working for the rubber producing companies like maxxis but for sure its great insight although i would have loved context on especific tire recomends and pressures for different types of riding? Hard choice when there is 490,000 tire options
This was so useful. Used the linked calculator and found I was about 10 psi too high. Let the excess air out and sure enough the bike feels much better and no noticeable change in speed over the last 3 weeks. Thanks Dylan + Josh 😃
Thanks Dylan I am one of those guys that ran as much pressure in my tire as I good back in the day. (1980) Know that I am a bit older (68) I can use every bit of help I can get. LOL I've been running lower pressure for years and it helps make the ride more enjoyable and at the same time faster. Good tires at the right air pressure, the best chain you can afford, best chain rings and cassette, then bearings and a frame that allows the peddle stroke to move the bike forward with no energy loss. With that in place we have NO Exceuses. Ride hard and with passion. Rick
I hear ya, I’m 68 also, raced bikes in 76, and mountain bikes in the 90’s. I always used 110 in my sew ups for races on the road. Now I use 100 lbs. in the rear, and 90 lbs in the front (700x25 clinchers) for rides. My mountain bike I use tubeless tires at 35 to 40 lbs. hard tail with 110mm Fox front shock. I still love to ride regularly.
Josh is amazing and definitely knows all the details and has all the experience working with cycling teams and testing products. I buy Silca products because of his insight.
I've been buying Silca products LONG LONG before Josh took over (I have an orange Silca Pista floor pump, and an ancient Silca Impero frame pump from over 52 YEARS AGO, when I first started racing on tubulars, both still fully functional!!). But yeah, this man most definitely knows his subject matter, and then some! (He might even be able to change my old school, died in the wool
I remember when Vredestein sold road tires with their advertisement that you can pump them up to 150 psi for decreased rolling resistance. It is interesting how things have changed.
Right on! We ALL have left countless watts on the course because of this. I found the insert discussion especially valuable! A deeper dive on this would be great! 👊🏻💥
I was drawn to tire inserts (Vittoria Airliner) for a 28mm road bike rim. I don't compete, but I was looking for added confidence that my tubeless setup would not leave me stranded in a rural area - - where I live. At the time I was running Continental GP 5k (TL), and they were notoriously hard to acquire, and even harder to mount. The Airliner just made it impossible for me. I never tried the insert with the Pirellis that I used to replace the GP5K's, but these are much easier to mount. In the end, with this new ease of installation, I have abandoned the inserts for the road bike, in favor of carrying a few patches, a boot, and an innter tube.
Very interesting! As a downhill/enduro bro, I actively look for a tyre with high hysterisis to keep grip on trails. Michelin tyres are a great example; very low durometer, very slow rebound. Those characteristics keep the tyre from feeling bouncy or "pingy" when riding through fast, chunky sections.
I like the discussion. Remember years ago, seeing a set of roll down tests of different tires and pressures, and a 'quick and dirty' correlation between how easy it was to deflect the UNINFLATED tire on say the sales rack and the rolling resistance; the easier to deflect, the easier to roll. Goes along with the hysteresis losses examined in the vid. Not foolproof and lots of qualifications but workable.
Great content. Great guest. Love the MG podcast. Please consider a conversation with Jan Heine, Rene Herse. If I recall correctly, Josh has hinted on the MG podcast that he may disagree with some of Jan's findings/testing/data on wider tires not being slower. If you could get a full length panel discussion with both of those guys - THAT would be gold. Keep up the good work, Dylan.
I definitely agree. It's hard to have a conversation about low tire pressure and rolling resistance without mentioning the huge contribution of Jan Heine!
After looking into the TIRE PRESSURE CALCULATOR and seeing how low the suggested tire pressure should be, I'm very enthusiastic to try it out! It's pretty sweet tool. Thank you for the insight!
@@ighfirlee If I were to worry about damaging my bike, I would ride slow, flat, boring tail trails... However, I can't worry about that! I would rather have the traction to make the turn and grip to dirt accordingly! Plus, my ENVE carbon rims have a lifetime warranty :) Ride On!
Engineer here, the reason low pressure is faster is down to idea gasses being perfectly elastic, meaning that compressing air is much more efficient than compressing your tire will ever be, making the tire lower pressure puts a lot more of the burden of deforming on the air rather than the tire. That's the real reason it's faster to run lower pressure
Mmmm, I would push back on that. (Pun unintentional but I'll roll with it). Ideal gas which behaves adiabatically is a valid first order assumption, but that would mean that it's not absorbing any of the energy. Thus, if we limit the control volume to the tire and air, the losses are due to inelastic deformation of the tire. However, I suspect that if we expand the control volume to include the entire bike & rider system, the power required to vibrate the mass of the system is a function of both tire pressure (neglecting sidewall stiffness), and surface roughness of the road. Thus, I would expect for perfectly smooth surfaces maximum tire pressure to be fastest. I would speculate based on the observed trend that an optimal tire pressure exists for a given roughness, that what I am assuming are vibratory losses scale as a function of pressure faster than tire deformation. (At least in the local space of sane tire pressures.) I suppose at the limit one gets either train wheels, or that one time JPL made 20 foot tall experimental rover tires made of parachute nylon inflated to something like 0.5psi, which were super efficient when going over giant boulders
Yes, please do more in this style! And definitely let us hear the immediate follow-on from this one. I'm on Tubolight in two different wheelsets per your recommendation and I'm convinced they (insterts in general rather than tubolight specifically) are the most underrated tech in gravel/cx at the moment. It was really fascinating to hear more of the science behind how and why they work and what sets different types apart from one another!
Really enjoyed this. So many interviewers love to jump in and take the show. But this was an interesting dude and you kept the convo moving forward. Loved it.
My experience is that the more expensive lightweight high-performance racing tires seem to be more prone to punctures . They usually have thiner sidewalls and less rubber overall in their construction.
Of course, but it isn't a 1 to 1 correspondence. The Continental 5000S variants for instance are very fast and pretty durable. As you go to tires much faster than that, you need to consider the course, and replace them sooner.
Explanations were very understandable and made sense. This content and others that you have shown have helped shift my perspective. That's been very helpful and have provided for a more enjoyable experience on and off the road. Thanks.
Super interesting discussion. I felt like we could have kept going with the topic. I think it’s nice you’ve brought in industry experts and pioneers to discuss a subject. Would love to see more. Maybe you have podcasts in your future?
The rheology of tires and the rubber compounds used to make them is so interesting. The balance between elasticity and energy dissipation in polymer systems especially in the context of real world performance is very fascinating to study.
So you are confirming something I've been observing for a while but never really checked deeply. I've been thinking about this loss of energy when going with high pressure on road with loose gravels
Absolutely outstanding video; your contributor Josh was excellent and informative - the perfect mix of technology, application and real-world knowledge.
Yes, this was a helpful video and my tire pressure was too high 10 PSI in the front and 20 PSI in the back. If you are on a track having high pressure and thin tires is the way to go. However, on the road with thin tires may be fast but if you get flats your gain is not worth much. I went on a bike ride and I saw other riders getting flats left and right and I did not get any flats. I think due to poor tire selection that many riders were getting flats and it took them out of the ride for a chunk of time.
So the days of two people putting as much force into their pumps to get 150 lb into 23 mm tyres have gone .I m thankful for seeing this vid.Used the Silka tool and lowered my 25 mm s to 80 lb and I m not only more comfy I ve already beat my 30 mile time on my usual course plus I m too bothered about bad gritty roads now .Handlebar buzz also nearly all gone
Great conversation,Dylan. On a side note, while understanding this was a completely different setup, the audio of your voice was significantly better sounding than recording in your (assuming) garage. Was much easier to listen to.
Unreal stuff. Way too much info that I have been looking at, from the silica wax vs one I'm using, to the vittoria foam inserts added resistance. That man is a wealth of info.
Hi Guys, I like your talk about tires and tire pressure. Because of it I tell you what are three players which influence RRC on the smooth drum: hysteresis, deformatin and volume of material Those tree players have in paralel impact to: wet grip, robustness, footprint, stiffness - > effect: grip, durability handling &comfort. Good balance of tire design or selection is key to success 😊
Hi Dylan your my go to guy for everything cycling racing related, your very specific in you videos and all the stuff is 100% related to my cycling,, keep it up, don’t change a thing, your by far the most informative
This is what I like the science and engineering part on how to be more efficient and faster . In this case it's about rolling resistance and how to maximize that to a riders advantage . That's why constant tinkering can help to improve performance . It can be 30 percent or more of your overall effort figuring things out . If not your wasting your brain power and just focusing on athleticism . Now some ( not many ) can rely on that but most of the rest will have to find an advantage to keep up .
I'm so glad you asked about the inserts. (I was not surprised you did though!) I don't think I've ever heard authoritative, objective information on them before.
Jan Heine from Rene Herse Cycles was describing this 15 to 20 years ago and got a lot of flack for it. He did a lot of test with power meters and also with different tire width to prove his findings. Still today there are riders who still believe in maxing out their tire pressures and has still yet to figure it out. Great video, I have heard Josh Poertner talk about this in the past and together with Jan Heine.
Great video.. really love Josh.. he really thinks outside the box and challenges the general consensus.. WHICH IS AWESOME!! I’ve followed his and Tom Anhalts thinking on this in great detail.. all great stuff! VeloNews’ did an analysis where they used a air shock as stand-in for a ‘flappy meat bag’ (aka a rider 😀) not sure everyone noticed, but if you look carefully at data it actually demonstrates that some of the attributes that you might assume would be predicted to be correlated with optimal tire pressure e.g. tire width and tire rolling resistance are not. These are the inputs for for tire calculators like Silcas’ which means that these calculators are not in fact good tools for determining optimal tire pressure.. inconvenient truth that each individual tire appears to have characteristics that make higher or lower pressure faster or slower.. cannot make generalizations.. my hypothesis is that this is due to a particular tire of particular size having its own resonant frequencies that make impedance assumption about impedance losses not as predictable as you might assume.. so in fact the only way to know the optimal tire pressure for a tire on a particular surface is to test THAT on THAT surface..
Adding some diversity to the channel format is good. We all enjoy your scientific format, but branching out can be good, and I found this chat interesting. Maybe once the race calendar starts you might want to do a video with some of the new teammates. Unbound pre or post race video with The jukebox crew.
Your video helped me to understand the 'why' behind the what better than others have. I knew that a 'more supple' sidewall helped reduce resistance. Now I have a better sense for why. That's cool and thank you.
Love it, Dylan! I like letting the specialists in their field figure it all out, such as yourself. Then I can just go ride smarted not harder and go faster, because who doesn't want to go faster.
Dylan, Really good video. Your training videos are the best but introducing other topics/styles such as this is really interesting. Great to learn from experts.
Very interesting video, However I would like to add two other consideration for tire pressure. 1. Higher pressure makes descending more stable\ 2. Higher pressure is more puncture resistant when biking on more marginal roads, that have potholes. To me that is a big consideration not be stranded with a flat tire on a remote road
Dylan, loved the content but I actually love the typical format of scientific analysis with a touch of personal perspective. Either way will keep watching! Best mtb training info out there.
Interesting different format/directions for a video on your channel. Personally my take on this specific question is that I used to worry about tyre selection and tyre weight and tyre pressure in terms of maximising my speed… until I realised that it was all pointless and the one thing that cost me the most time was simply avoiding punctures. Now I just run as bulletproof a setup as I can get and cover ground both faster overall and with less annoying stoppages/mechanicals. Perhaps marginal gains in rolling resistance matter more to pros who have a team car and can simply swap wheels/bikes if they puncture but for the rest of us it does seem to make more sense to simply aim for avoiding mechanicals and all other considerations really are secondary or irrelevant
Tubeless solved the puncture problem years back. I've ridden 28mm road tyres on brutal MTB type terrain and not exactly tentatively either, sometimes it's chasing KOMs. Though I swapped to light 33mm CX tyres after realizing they were just as fast on road, and obviously faster/more comfortable on rougher stuff.
Interesting format. I‘d love to see more, especially on the MTB side. I plan to race XCM again this years after a long break and on a 5 or more hour race a few watts saved make a difference.
Nice talking. It make me think that FMB try to make his tires thiner and softer. Many Paris-Roubaix were win with them from 2008 to almost 2015 I think ! I love the way your talking about de foam that is being push and don't have the time to reform so you just "hit the rigid". More you have a tire which filter the vibration of the road, less you loss watt
Selecting the right chain lube can save 1.1mph based on my last ride. I just bought a specialized Roubaix sl8 comp. Im in love! Its been on 3 rides. 1 shakedown ride, then some adjusting, then a second ride. After the second ride i converted my drivetrain over to wax, degreasing everything and waxing the chain. And i just got back from my 3rd ride. My 1st ride averaged 14.5 mph. But i was tinkering with the computer on and spinning around the block a couple times. My second ride was the 1st real ride. After giving myself a makeshift bike fit (fixed my pain!). The 2nd ride I averaged 15.2mph over 20 miles. Then i switched to wax, got a spare tube for a longer ride, and i was off. 40 miles later i had averaged 16.3mph, a 1.1mph increase while also doubling the distance. It was my first time hitting 40 miles, its been a goal for so long i lost track. I got close months ago when i was new to biking, but my body wasnt ready and i was trying far too hard i came home @ 38 miles stoked to be so close only to find i popped a blood vessel in my eye. I gave up the goal for a while and learned about zone 2 training. Next goal is 50 miles! I almost pushed for it today...😅
Great Video. I enjoy that you vary the style of your videos. The scientific-paper ones are nice, but interviews and alternative approaches to topics really spice up your channel. I like it. Also: Great topic here
Proceed with caution.. haven't experience myself, but word is that these inserts are great functionally.. but make removal of tire almost impossible... reports that teams that used them literally cut tires off to remove rather than trying to pry them off with levers 😳
I've had no issues with my Vittoria gravel insert. I only installed one on my rear wheel since I didn't want to spend for both wheels. They were really easy to install. Basically just like an inner tube. They give me that extra piece of mind when I do rougher trails and small jumps on the gravel bike. I'd say it's worth for the rear wheel. 😊
I have a MTB which I removed the suspension to add a carbon rigid fork. But the mayor update was to go tubeless with Schwalbe G one speed tires. Now my bike feels like a complete new bike, so fast. With regular mtb tires on flat road 33-35km/h was hard to maintain and go above was crazy, now with the same effort I can go 55km/h. I have right now a fun gravel bike.Of course the traction is not the same off road but the speed is amazing (I’m not fan to go down of the hill, I love to climb in my bike fast)
One of the best and most tecnical videos about tires I have ever seen. And from my experience I agree 100%. On the Silca link I miss the rim width variable and afew more details like disc or rim brake, comfort average or performance and also dry, mixed or wet surface, that in the old “my mavic” app were. But still very sweet link
To be fair, it asks for "measured width" of the tire, which takes into account the effects of rim internal width (i.e. how it affects the width of a particular tire when mounted). Brake type doesn't have any appreciable effect on the pressure requirements either.
Wow, amazing video, very well explained. Would be interesting to make a video about different tyre puncture protection and their cost in watts (for road if possible) and if it's worth it, for example vittoria cinturato velo tlr, as i found on bicyclerollingresistance those tyres are the most puncture proff yet not the lowest rolling resistance as they were expected at that puncture score.
Thanks Dylan for sharing. Quite fascinating. We were debating this issue recently in our cycling club. I shared your video with our members. We may all be faster next weekend LOL
I liked the commentary. I'm glad you found someone with experience and an open mind to change. Josh Poertner strikes that balance of modern thinkers in an industry sometimes that is stuck in its ways. It was refreshing to hear someone state that comfort and traction are real considerations. It was also nice to hear that he agrees that roller tests do scale to real world results. Arguing that there is little or no value in roller tests is the new vogue of the retro grouch. Finally, my take is that the product mentions were relevant, and I didn't feel he was a shill for one company or brand. Nice.
Exactly...as long as you stay below the "breakpoint" pressure for a particular tire/load/speed/surface, the results scale exactly. In fact, that's how the "breakpoint pressure" was first identified, i.e. the pressure at which the roller data diverged from the field test data...which, of course means that as long as you're prudent about pressures, they're a valuable (and relatively easy) testing methodology.
Sometimes, I only increase pressure to avoid pinch flats on the metal manhole covers I encounter on my road bike... with my commuter bike, with Schwalbe Marathons, (and a bigger carcass anyway) I have much lower pressures. I'm a heavy guy (100kg) and always had the idea that more pressure was a compensation for my weight so as to not deform the tyre too much... I know that higher pressures on my indoor trainer (driven off the tyre, not via the cassette) is a better thing, I notice the difference in my numbers, but that is a very controlled environment... This video raises some interesting points, and like you do with your other subjects, uses actual science stuff to make the case... BHD might reconsider running those solid silicone tyres he uses for chasing KoM's...
Ive put conti 5000 on my bikes. I love the feel on long rides and mixed surfaces plus rhey give a lot of confidence on long fast alpine descents. Im 181 and 72kg on a 7.5kg s works. Calculator tells me to inflate 6.3 but i tend to underinflate to about 5.5. Subjecrive to accuracy of my pump meter. 25mm wide
This was awesome. I really learned a lot of things from this discussion that I don't really hear anywhere else. Thanks for sharing. And I'm definitely going to check out that podcast.
If you are looking to take your training to the next level then consider one of my online science based training plans available here: www.trainingpeaks.com/coach/dylanjohnsontraining#trainingplans
If wider tires have lower rolling resistance and assuming this does not apply to bicycle tires only, then that means putting wider tires in cars can actually improve efficiency?
Oooooooooooooooo
@@sepg5084 oooooooooooooooo ooooooooooooooooooooooooooooooooooooooooooooooooopoooopooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooopp
@@sepg5084 as it was said in the video, there is a limit in both directions. As far as i know, car tyres are already very very wide as the are optimised for grip, not for rolling efficiency. Look at the electric car tyres where efficiency (= range) is critical, the are much thinner :)
Let me know if you liked this style of video and if I should include more guests in the future. There is a lot more from this conversation that I plan on releasing.
Find your optimal tire pressure with the Silca Professional Tire Pressure Calculator:
silca.cc/pages/sppc-form
Find out which tires are faster or slower with BicycleRollingResistance.com:
www.bicyclerollingresistance.com/
Great content. Thanks. I am going out to lower my psi. lol
Great information and insight into tire/tube air pressures. Very interesting and educational. Thanks for this excellent material...
Hi Dylan, I very much enjoyed this style of video. I was hoping Josh/you would get into discussing the pros/cons of various tread types & tire manufacturers. I've been on nothing but Rene Herse tires for years -> Barlow Pass 38mm slicks which actually measure 43mm on my FSE 27mm internal width wheels... However, I've had my eye on some Vittoria tires as well. Thanks again for the great content!!
Your normal videos are better.
Bro you left me hanging! I wanna hear the second part
I got a new bike! I ran 25mm tires at 120 psi on my old bikes for many years. My new bike came with 32mm tires. I used a tire pressure calculator and I currently run them at 55/60. I don't think these tires roll faster, but they are much more comfortable on the chip seal road surfaces I ride around here. I'm old, so comfort is a priority.
This is great. I love hearing people who know what they're talking about address issues that we usually don't have any good data on
There's lots of good data out there and has been for the last couple of decades. Guys like Tom Anhalt have been testing tires for the longest time...
Id say the big guys are actually working for the rubber producing companies like maxxis but for sure its great insight although i would have loved context on especific tire recomends and pressures for different types of riding?
Hard choice when there is 490,000 tire options
This was so useful. Used the linked calculator and found I was about 10 psi too high. Let the excess air out and sure enough the bike feels much better and no noticeable change in speed over the last 3 weeks. Thanks Dylan + Josh 😃
Thanks Dylan I am one of those guys that ran as much pressure in my tire as I good back in the day. (1980) Know that I am a bit older (68) I can use every bit of help I can get. LOL I've been running lower pressure for years and it helps make the ride more enjoyable and at the same time faster. Good tires at the right air pressure, the best chain you can afford, best chain rings and cassette, then bearings and a frame that allows the peddle stroke to move the bike forward with no energy loss. With that in place we have NO Exceuses. Ride hard and with passion. Rick
I hear ya, I’m 68 also, raced bikes in 76, and mountain bikes in the 90’s. I always used 110 in my sew ups for races on the road. Now I use 100 lbs. in the rear, and 90 lbs in the front (700x25 clinchers) for rides. My mountain bike I use tubeless tires at 35 to 40 lbs. hard tail with 110mm Fox front shock. I still love to ride regularly.
Josh is amazing and definitely knows all the details and has all the experience working with cycling teams and testing products. I buy Silca products because of his insight.
I've been buying Silca products LONG LONG before Josh took over (I have an orange Silca Pista floor pump, and an ancient Silca Impero frame pump from over 52 YEARS AGO, when I first started racing on tubulars, both still fully functional!!).
But yeah, this man most definitely knows his subject matter, and then some!
(He might even be able to change my old school, died in the wool
I remember when Vredestein sold road tires with their advertisement that you can pump them up to 150 psi for decreased rolling resistance. It is interesting how things have changed.
Track Riders 150 to 200 psi
I always Ride @ 120 - 125 psi Clinchers Specialized Training Tyres
@@Robert-mn8gc too much
@@Robert-mn8gcwell, Dygert just won the pursuit at worlds running tubeless 25mm tires that were probably under 90psi
@@veganpottertheveganuh...no. 150+ psi more likely
@lunam7249 no, the beads would blow on the tires they used at 150psi sitting still. No way could they handle the force of the banks on the track
Needs an interviewer who knows what he's talking about. Let Backwards Hat Dylan take the next one.
Seriously though, great video!
Right on! We ALL have left countless watts on the course because of this. I found the insert discussion especially valuable! A deeper dive on this would be great! 👊🏻💥
I was drawn to tire inserts (Vittoria Airliner) for a 28mm road bike rim. I don't compete, but I was looking for added confidence that my tubeless setup would not leave me stranded in a rural area - - where I live. At the time I was running Continental GP 5k (TL), and they were notoriously hard to acquire, and even harder to mount. The Airliner just made it impossible for me.
I never tried the insert with the Pirellis that I used to replace the GP5K's, but these are much easier to mount. In the end, with this new ease of installation, I have abandoned the inserts for the road bike, in favor of carrying a few patches, a boot, and an innter tube.
This style of video is a nice change of pace from the regular "what do the studies say" videos. I like both styles.
Love love love this content. This channel is all about getting faster in a practical data based way. Give us more!
Very interesting! As a downhill/enduro bro, I actively look for a tyre with high hysterisis to keep grip on trails. Michelin tyres are a great example; very low durometer, very slow rebound. Those characteristics keep the tyre from feeling bouncy or "pingy" when riding through fast, chunky sections.
I like the discussion. Remember years ago, seeing a set of roll down tests of different tires and pressures, and a 'quick and dirty' correlation between how easy it was to deflect the UNINFLATED tire on say the sales rack and the rolling resistance; the easier to deflect, the easier to roll. Goes along with the hysteresis losses examined in the vid. Not foolproof and lots of qualifications but workable.
Yes please release more of this conversation. The insight offered is great and I lost track of time listening to it.
This is a must podcast ! Can’t wait for the rest of this conversation.
Definitely think you doing a podcast is the way forward !!
Great content. Great guest. Love the MG podcast. Please consider a conversation with Jan Heine, Rene Herse. If I recall correctly, Josh has hinted on the MG podcast that he may disagree with some of Jan's findings/testing/data on wider tires not being slower. If you could get a full length panel discussion with both of those guys - THAT would be gold. Keep up the good work, Dylan.
I definitely agree. It's hard to have a conversation about low tire pressure and rolling resistance without mentioning the huge contribution of Jan Heine!
Excellent! Your guest was very knowledgable and articulate
After looking into the TIRE PRESSURE CALCULATOR and seeing how low the suggested tire pressure should be, I'm very enthusiastic to try it out! It's pretty sweet tool. Thank you for the insight!
u will regret it when u hit a pothole at high speed. Bye bye to ur carbon rim.
@@ighfirlee If I were to worry about damaging my bike, I would ride slow, flat, boring tail trails... However, I can't worry about that! I would rather have the traction to make the turn and grip to dirt accordingly! Plus, my ENVE carbon rims have a lifetime warranty :) Ride On!
Engineer here, the reason low pressure is faster is down to idea gasses being perfectly elastic, meaning that compressing air is much more efficient than compressing your tire will ever be, making the tire lower pressure puts a lot more of the burden of deforming on the air rather than the tire. That's the real reason it's faster to run lower pressure
Define “lower” pressure.
@@traderstatusquo a gauge pressure lower than the expectation that most people have (70psi being faster than 110 psi for a 150lb rider)
Mmmm, I would push back on that. (Pun unintentional but I'll roll with it). Ideal gas which behaves adiabatically is a valid first order assumption, but that would mean that it's not absorbing any of the energy. Thus, if we limit the control volume to the tire and air, the losses are due to inelastic deformation of the tire.
However, I suspect that if we expand the control volume to include the entire bike & rider system, the power required to vibrate the mass of the system is a function of both tire pressure (neglecting sidewall stiffness), and surface roughness of the road. Thus, I would expect for perfectly smooth surfaces maximum tire pressure to be fastest. I would speculate based on the observed trend that an optimal tire pressure exists for a given roughness, that what I am assuming are vibratory losses scale as a function of pressure faster than tire deformation. (At least in the local space of sane tire pressures.)
I suppose at the limit one gets either train wheels, or that one time JPL made 20 foot tall experimental rover tires made of parachute nylon inflated to something like 0.5psi, which were super efficient when going over giant boulders
This’s only true on rough surfaces. The smoother the surface, the higher the pressure, the lower the rolling resistance.
@@traderstatusquo jordan peterson is that you?
Yes, please do more in this style! And definitely let us hear the immediate follow-on from this one. I'm on Tubolight in two different wheelsets per your recommendation and I'm convinced they (insterts in general rather than tubolight specifically) are the most underrated tech in gravel/cx at the moment. It was really fascinating to hear more of the science behind how and why they work and what sets different types apart from one another!
Really enjoyed this. So many interviewers love to jump in and take the show. But this was an interesting dude and you kept the convo moving forward. Loved it.
Damn, that was just straight up excellent. So robustly and concretely communicated.
This guy is awesome. Just straight shooting without any garbage P/R words.
I'm a big fan of Josh Poertner! Thanks for having him on the show! 🙌🏻
My experience is that the more expensive lightweight high-performance racing tires seem to be more prone to punctures . They usually have thiner sidewalls and less rubber overall in their construction.
It is. Cheaper tires are always more puncture resistance, at the cost of rolling resistance, comfort (higher TPI) and weight.
They last less too the more expensive they are .
Of course, but it isn't a 1 to 1 correspondence. The Continental 5000S variants for instance are very fast and pretty durable. As you go to tires much faster than that, you need to consider the course, and replace them sooner.
Awesome video! Dylan you lead the way with science based cycling content! Really an eye opener when it comes to tires and pressure.
Great video. Post up the entire conversation. I would listen to the whole thing!
I watch this video every season. Idk why but the third time watching still fascinates me.
Glad you asked insert question. I’ve been curious
Excellent, having two people talking makes it more entertaining. Very informative!
Explanations were very understandable and made sense. This content and others that you have shown have helped shift my perspective. That's been very helpful and have provided for a more enjoyable experience on and off the road. Thanks.
Super interesting discussion. I felt like we could have kept going with the topic. I think it’s nice you’ve brought in industry experts and pioneers to discuss a subject. Would love to see more. Maybe you have podcasts in your future?
So glad you asked about inserts. Was thinking just that when he was explaining hysteresis 👍🏼 super interesting info, thanks for sharing!
The rheology of tires and the rubber compounds used to make them is so interesting. The balance between elasticity and energy dissipation in polymer systems especially in the context of real world performance is very fascinating to study.
You’ll be a great curator interviewer of this type of content it’s a great complement to your other work
So you are confirming something I've been observing for a while but never really checked deeply.
I've been thinking about this loss of energy when going with high pressure on road with loose gravels
Absolutely outstanding video; your contributor Josh was excellent and informative - the perfect mix of technology, application and real-world knowledge.
Great content, Dylan I would be a non-stop listener if you had a podcast.
Yes, this was a helpful video and my tire pressure was too high 10 PSI in the front and 20 PSI in the back.
If you are on a track having high pressure and thin tires is the way to go. However, on the road with thin tires may be fast but if you get flats your gain is not worth much. I went on a bike ride and I saw other riders getting flats left and right and I did not get any flats. I think due to poor tire selection that many riders were getting flats and it took them out of the ride for a chunk of time.
So the days of two people putting as much force into their pumps to get 150 lb into 23 mm tyres have gone .I m thankful for seeing this vid.Used the Silka tool and lowered my 25 mm s to 80 lb and I m not only more comfy I ve already beat my 30 mile time on my usual course plus I m too bothered about bad gritty roads now .Handlebar buzz also nearly all gone
Great conversation,Dylan. On a side note, while understanding this was a completely different setup, the audio of your voice was significantly better sounding than recording in your (assuming) garage. Was much easier to listen to.
Unreal stuff. Way too much info that I have been looking at, from the silica wax vs one I'm using, to the vittoria foam inserts added resistance. That man is a wealth of info.
Hi Guys, I like your talk about tires and tire pressure. Because of it I tell you what are three players which influence RRC on the smooth drum: hysteresis, deformatin and volume of material
Those tree players have in paralel impact to: wet grip, robustness, footprint, stiffness - > effect: grip, durability handling &comfort.
Good balance of tire design or selection is key to success 😊
Just the little intro clip with the pressure calculator was new to me. Thank for that .
Hi Dylan your my go to guy for everything cycling racing related, your very specific in you videos and all the stuff is 100% related to my cycling,, keep it up, don’t change a thing, your by far the most informative
This is what I like the science and engineering part on how to be more efficient and faster . In this case it's about rolling resistance and how to maximize that to a riders advantage . That's why constant tinkering can help to improve performance . It can be 30 percent or more of your overall effort figuring things out . If not your wasting your brain power and just focusing on athleticism . Now some ( not many ) can rely on that but most of the rest will have to find an advantage to keep up .
Loved hearing Josh talk tires!
This kind of detail will save a lot of tears and guess work. Great stuff👍
I'm so glad you asked about the inserts. (I was not surprised you did though!) I don't think I've ever heard authoritative, objective information on them before.
Great vid. Look forward to the rest of that conversation!
This video actually got better as it went along. Thumbs up!
Yes,more like this please Dylan.
Great video. Great guest and information. Format is good and only adds to the content you provide!
Jan Heine from Rene Herse Cycles was describing this 15 to 20 years ago and got a lot of flack for it. He did a lot of test with power meters and also with different tire width to prove his findings. Still today there are riders who still believe in maxing out their tire pressures and has still yet to figure it out. Great video, I have heard Josh Poertner talk about this in the past and together with Jan Heine.
Why would publicists take any interest in the arcane intricacies of bicycle tyres?
This was awesome, he was talking to us and not "at" us, very clear and super interesting
This was the excellent, please keep providing this type of content. Thanks!
Great video.. really love Josh.. he really thinks outside the box and challenges the general consensus.. WHICH IS AWESOME!! I’ve followed his and Tom Anhalts thinking on this in great detail.. all great stuff!
VeloNews’ did an analysis where they used a air shock as stand-in for a ‘flappy meat bag’ (aka a rider 😀) not sure everyone noticed, but if you look carefully at data it actually demonstrates that some of the attributes that you might assume would be predicted to be correlated with optimal tire pressure e.g. tire width and tire rolling resistance are not. These are the inputs for for tire calculators like Silcas’ which means that these calculators are not in fact good tools for determining optimal tire pressure.. inconvenient truth that each individual tire appears to have characteristics that make higher or lower pressure faster or slower.. cannot make generalizations.. my hypothesis is that this is due to a particular tire of particular size having its own resonant frequencies that make impedance assumption about impedance losses not as predictable as you might assume.. so in fact the only way to know the optimal tire pressure for a tire on a particular surface is to test THAT on THAT surface..
Adding some diversity to the channel format is good. We all enjoy your scientific format, but branching out can be good, and I found this chat interesting.
Maybe once the race calendar starts you might want to do a video with some of the new teammates. Unbound pre or post race video with The jukebox crew.
Your video helped me to understand the 'why' behind the what better than others have. I knew that a 'more supple' sidewall helped reduce resistance. Now I have a better sense for why. That's cool and thank you.
Love it, Dylan! I like letting the specialists in their field figure it all out, such as yourself. Then I can just go ride smarted not harder and go faster, because who doesn't want to go faster.
Dylan, Really good video. Your training videos are the best but introducing other topics/styles such as this is really interesting. Great to learn from experts.
Good Stuff, I just bought one of these Vittoria inserts to try on the gravel setup here soon. So glad to hear he gave some real world info on it.
Fascinating would love to hear more about tire inserts.
Very interesting video,
However I would like to add two other consideration for tire pressure.
1. Higher pressure makes descending more stable\
2. Higher pressure is more puncture resistant when biking on more marginal roads, that have potholes.
To me that is a big consideration not be stranded with a flat tire on a remote road
Super interesting! Back when I was working in a shop it was all about the highest psi possible. If you ran lower, it was just for comfort.
Dylan, loved the content but I actually love the typical format of scientific analysis with a touch of personal perspective. Either way will keep watching! Best mtb training info out there.
I definitely would love to see more of this kind of videos!
Interesting different format/directions for a video on your channel. Personally my take on this specific question is that I used to worry about tyre selection and tyre weight and tyre pressure in terms of maximising my speed… until I realised that it was all pointless and the one thing that cost me the most time was simply avoiding punctures. Now I just run as bulletproof a setup as I can get and cover ground both faster overall and with less annoying stoppages/mechanicals. Perhaps marginal gains in rolling resistance matter more to pros who have a team car and can simply swap wheels/bikes if they puncture but for the rest of us it does seem to make more sense to simply aim for avoiding mechanicals and all other considerations really are secondary or irrelevant
So whats your pick?
@@romelagz Schwalbe Marathon Plus SmartGuard? :)
Tubeless solved the puncture problem years back.
I've ridden 28mm road tyres on brutal MTB type terrain and not exactly tentatively either, sometimes it's chasing KOMs.
Though I swapped to light 33mm CX tyres after realizing they were just as fast on road, and obviously faster/more comfortable on rougher stuff.
Awesome video! Great to hear an expert talking tech
Interesting format. I‘d love to see more, especially on the MTB side. I plan to race XCM again this years after a long break and on a 5 or more hour race a few watts saved make a difference.
Awesome video with a lot of good info, looking forward to more
Nice talking. It make me think that FMB try to make his tires thiner and softer. Many Paris-Roubaix were win with them from 2008 to almost 2015 I think ! I love the way your talking about de foam that is being push and don't have the time to reform so you just "hit the rigid". More you have a tire which filter the vibration of the road, less you loss watt
Pushing the limits of nerdy content. Love it 😁
Thank you for this video. The knowledge about the tires really helped me.
Selecting the right chain lube can save 1.1mph based on my last ride.
I just bought a specialized Roubaix sl8 comp. Im in love! Its been on 3 rides. 1 shakedown ride, then some adjusting, then a second ride. After the second ride i converted my drivetrain over to wax, degreasing everything and waxing the chain. And i just got back from my 3rd ride.
My 1st ride averaged 14.5 mph. But i was tinkering with the computer on and spinning around the block a couple times. My second ride was the 1st real ride. After giving myself a makeshift bike fit (fixed my pain!). The 2nd ride I averaged 15.2mph over 20 miles. Then i switched to wax, got a spare tube for a longer ride, and i was off. 40 miles later i had averaged 16.3mph, a 1.1mph increase while also doubling the distance.
It was my first time hitting 40 miles, its been a goal for so long i lost track. I got close months ago when i was new to biking, but my body wasnt ready and i was trying far too hard i came home @ 38 miles stoked to be so close only to find i popped a blood vessel in my eye. I gave up the goal for a while and learned about zone 2 training. Next goal is 50 miles! I almost pushed for it today...😅
Great Video. I enjoy that you vary the style of your videos. The scientific-paper ones are nice, but interviews and alternative approaches to topics really spice up your channel. I like it. Also: Great topic here
This was amazing. Very much appreciated an additional expert to cover such a topic.
Great video. As someone obsessed with gravel tires, this was very insightful.
this is so cool and I love how technical it is
You make the best stuff ... thanks and keep it coming!
This is awesome. I am a tire-phyle and eat up this kind of information. Thanks...
Great video. Please do one solely focused on mountain bike tires! Thank you!
This was really interesting! I had wondered if the Vittoria inserts were worth the cost, and now I think they might actually be.
Proceed with caution.. haven't experience myself, but word is that these inserts are great functionally.. but make removal of tire almost impossible... reports that teams that used them literally cut tires off to remove rather than trying to pry them off with levers 😳
I've had no issues with my Vittoria gravel insert. I only installed one on my rear wheel since I didn't want to spend for both wheels. They were really easy to install. Basically just like an inner tube. They give me that extra piece of mind when I do rougher trails and small jumps on the gravel bike. I'd say it's worth for the rear wheel. 😊
Good stuff, Dylan. I really enjoyed the conversation. Very informative.
Bro I would watch the whole podcast, post it up!
This was great. I listened to the entire session. Please share the rest of it.
Definitely enjoyed this style of video and came away with some good takeaways.
I have a MTB which I removed the suspension to add a carbon rigid fork. But the mayor update was to go tubeless with Schwalbe G one speed tires. Now my bike feels like a complete new bike, so fast. With regular mtb tires on flat road 33-35km/h was hard to maintain and go above was crazy, now with the same effort I can go 55km/h. I have right now a fun gravel bike.Of course the traction is not the same off road but the speed is amazing (I’m not fan to go down of the hill, I love to climb in my bike fast)
most informative bike video of the year.
I'm really happy that I found your channel ! The content is super interesting !
One of the best and most tecnical videos about tires I have ever seen. And from my experience I agree 100%. On the Silca link I miss the rim width variable and afew more details like disc or rim brake, comfort average or performance and also dry, mixed or wet surface, that in the old “my mavic” app were. But still very sweet link
To be fair, it asks for "measured width" of the tire, which takes into account the effects of rim internal width (i.e. how it affects the width of a particular tire when mounted). Brake type doesn't have any appreciable effect on the pressure requirements either.
Wow, amazing video, very well explained. Would be interesting to make a video about different tyre puncture protection and their cost in watts (for road if possible) and if it's worth it, for example vittoria cinturato velo tlr, as i found on bicyclerollingresistance those tyres are the most puncture proff yet not the lowest rolling resistance as they were expected at that puncture score.
Thanks Dylan for sharing. Quite fascinating. We were debating this issue recently in our cycling club. I shared your video with our members. We may all be faster next weekend LOL
I liked the commentary. I'm glad you found someone with experience and an open mind to change. Josh Poertner strikes that balance of modern thinkers in an industry sometimes that is stuck in its ways. It was refreshing to hear someone state that comfort and traction are real considerations. It was also nice to hear that he agrees that roller tests do scale to real world results. Arguing that there is little or no value in roller tests is the new vogue of the retro grouch.
Finally, my take is that the product mentions were relevant, and I didn't feel he was a shill for one company or brand. Nice.
Exactly...as long as you stay below the "breakpoint" pressure for a particular tire/load/speed/surface, the results scale exactly. In fact, that's how the "breakpoint pressure" was first identified, i.e. the pressure at which the roller data diverged from the field test data...which, of course means that as long as you're prudent about pressures, they're a valuable (and relatively easy) testing methodology.
Sometimes, I only increase pressure to avoid pinch flats on the metal manhole covers I encounter on my road bike... with my commuter bike, with Schwalbe Marathons, (and a bigger carcass anyway) I have much lower pressures. I'm a heavy guy (100kg) and always had the idea that more pressure was a compensation for my weight so as to not deform the tyre too much... I know that higher pressures on my indoor trainer (driven off the tyre, not via the cassette) is a better thing, I notice the difference in my numbers, but that is a very controlled environment...
This video raises some interesting points, and like you do with your other subjects, uses actual science stuff to make the case... BHD might reconsider running those solid silicone tyres he uses for chasing KoM's...
Ive put conti 5000 on my bikes. I love the feel on long rides and mixed surfaces plus rhey give a lot of confidence on long fast alpine descents. Im 181 and 72kg on a 7.5kg s works. Calculator tells me to inflate 6.3 but i tend to underinflate to about 5.5. Subjecrive to accuracy of my pump meter. 25mm wide
As a track rider I put 16 bars pressure, on the road i put only between 5.5 and 6.5 😅
This was awesome. I really learned a lot of things from this discussion that I don't really hear anywhere else. Thanks for sharing. And I'm definitely going to check out that podcast.
That was very interesting Dylan excellent job.