Absolutely! I have to ride on good and not-so-good pavement, so this video tells me what I need to know in a concise manner! Another great video #GTN Team !
Why is everyone so obsessed with speed? At least when it comes to recreational riding/commuting, don't we enjoy being on our bikes? So why do we want maximum possible speed thus shortening the time on the bike? I'm likely in the wrong comment section to make that argument. I commute on a 21lb 26" wheel Ti hardtail with an 80 mm travel fork with lockout. Riding Maxxis Maxlite 310g 1.5" tires--set around 40-50psi. With a road bike I could likely trim 15 minutes off my average commute time-but I don't really want to shorten the time on my bike. Certainly not worth spending 3K or more to acquire a decent road machine. On my XC race bike I can hit some trails, ride down steps, and off curbs during my commute with no worries. Anyone who thinks a 26er is a bad choice for commuting--I recently met a guy who worked as a bike courier in Vancouver for several years riding a 26er.
I switched to 28mm tires a few years ago, and now I won't ride anything else. In terms of comfort and speed and just overall feel of the bike, they are my absolute fave for both my road and Tri bikes. I ride 80PSI on the rear tire and 75PSI on the front. I'm 181cm and 75KG for reference.
@@gtn I don't think I would go wider. I feel 28mm checks all the boxes for me, which is good, because both of my bikes don't have the clearance for anything wider than 28mm. On my road bike they only just barely fit without rubbing on the frame.
@@ironmantooltime no I didn't change my wheels, I run Mavic R-SYS SLR wheelset, which can easily run a 28mm tire. I also run them tubeless, as they are a full tubeless rim setup, which is why they are awesome. no rim tapes or anything needed. Just put on a tubeless compatible tire, add sealant, and you are good to go :)
TT's and triathlons, 23/25 mm front and 25/28 mm rear, depending on rim width, weight, road surface, frame clearance, brake clearance, and speed. Pressure according to road surface. Don't ride too low of pressure due to potential pinch flats. Yes, you can pinch flat a tubeless tire, and you are screwed unless you have a tube, etc, to deal with it.
- Any bike tech question - Well... it depends... That's one thing I don't really appreciate about the biking, honestly. Sill, I can ignore most of it and enjoy my old bike with no pretense on being a top performer so... everyone's happy. 😉
This is so useful information. Specifically the part about matching tyre width with rim width. I bought a bike with carbon OEM wheels that optimised for 25mm. Now I know I can try 28mm on the back but not on the front. Great content.
I rewatched the GCN video, and they compared 28 to 32mm tyres, and found no difference at 30 kmh, but an advantage for 28mm tyres at 40 kmh. I note they were running this test on some 26mm wide external rims, which are not aerodynamically suited to either 28 or 32mm tyres. There are plenty of modern rims with 30-31 mm external width rims which are aero with 28 mm tyres. Finding wheels which are aero with 32mm tyres is a lot harder.
well explained, without promoting the propaganda of wider tires= always better (just because the industry is going that way now, same with the disc brake propaganda). GCN does just that...
Do tires of different widths really have the same rolling resistance? Or is it the lightly taller profile of the wider tires that is not taken into account when calculating rolling resistance, and thereby giving an edge to wider tires?
I am about 85kg (+/- 2 kg depending the time of the season). On my TT I have 23mm front and 25mm back. My wheels are 25mm outside width so the 23 in the front fits nicely. In the rear i think 25mm is as big as i can fit on my 2016 cervelo p3. Haven't really played with 28mm yet but can't possibly see me fitting 28s in the rear. On my road bike (older bike maybe 2010-2012) I can't fit anything bigger than 23mm on the back (It will rub during hard cornering, I tried it). Then i have my waaa bike.... the one i use when its nasty out or towing the kids... that one has 32 all around and feels pretty nice (this bike is an older schwim flatbar converted to drop bar as i upgraded my other bike...)!!
Great video, thank you James! You indicated a higher tire pressure is generally faster due to a higher casing tension (all else equal). Intuitively this makes sense but I know there’s been a recent trend towards lower tire pressure. I’m wondering what the science behind that trend is - I think it’s surface area?
It's implied on the video. It's because rolling resistance isn't the only energy loss. There is aerodynamic losses (also explained) but also vibration losses (hinted behind "comfort" but there's more to that). Vibration is an actual energy loss, it's not just a problem of comfort. Vibration is forward kinetic energy transformed into vertical kinetic energy (through small oscillation) that is then absorbed by the rider causing fatigue and by the bike causing heat. When only focusing on pure rolling resistance, we tend to over-inflate. If we want to minimize all the losses, it's better to soften a bit the tyre, causing a bit more rolling resistance but far less vibration loss. The sweet spot depending on the average "bumpy-ness/roughness" expected on the ride. The "sudden discovery" that rolling resistance isn't everything even performance-wise is the reason we start to go wider, even on pro peloton. To be able to ride a bit softer (optimize overall losses not just rolling) and keeping the same safety margin from pinch flat punctures.
Not much I think - it's more about having a smooth wheel to tyre interface. It gets much worse if the tyre's significantly wider than the rim. And this doesn't matter too much for shallow rims
@@themindgarage8938 Does not matter at all for shallow rims. At least does no negate the wider tires advantage. I estimated it on long descends with 23 - 25 - 28 mm tires. The 28 are faster and wider than rims. The 23 were "junk" stock and slowest, the others same model. I am not sure that "4 mm narrower" tires would aid to the aero advantage. But who knows? May be the dense air pocket will form and help?
Thin tyres harder pressure equals faster it’s a fact, don’t fall for the industry shite, oh I’m a team mech 20yrs, the cycle industry are just a money machine, stop them.
![[[OFFICIAL MV]] เอิ้นขวัญให้อ้าย- อ๊ะอาย สกุณาพร | ค่ายเพลงเป็นหนึ่ง](http://i.ytimg.com/vi/83x6L3X3qh0/mqdefault.jpg)
Is tyre pressure important to you? Let us know 🤔
Absolutely! I have to ride on good and not-so-good pavement, so this video tells me what I need to know in a concise manner!
Another great video #GTN Team !
Why is everyone so obsessed with speed? At least when it comes to recreational riding/commuting, don't we enjoy being on our bikes? So why do we want maximum possible speed thus shortening the time on the bike? I'm likely in the wrong comment section to make that argument. I commute on a 21lb 26" wheel Ti hardtail with an 80 mm travel fork with lockout. Riding Maxxis Maxlite 310g 1.5" tires--set around 40-50psi. With a road bike I could likely trim 15 minutes off my average commute time-but I don't really want to shorten the time on my bike. Certainly not worth spending 3K or more to acquire a decent road machine. On my XC race bike I can hit some trails, ride down steps, and off curbs during my commute with no worries. Anyone who thinks a 26er is a bad choice for commuting--I recently met a guy who worked as a bike courier in Vancouver for several years riding a 26er.
I switched to 28mm tires a few years ago, and now I won't ride anything else. In terms of comfort and speed and just overall feel of the bike, they are my absolute fave for both my road and Tri bikes. I ride 80PSI on the rear tire and 75PSI on the front. I'm 181cm and 75KG for reference.
Great to hear you have joined the wide tyre crew! Would you ever go wider? 👀
@@gtn I don't think I would go wider. I feel 28mm checks all the boxes for me, which is good, because both of my bikes don't have the clearance for anything wider than 28mm. On my road bike they only just barely fit without rubbing on the frame.
Hear hear
Did u change ur wheels or were they already suited to 28s?
@@ironmantooltime no I didn't change my wheels, I run Mavic R-SYS SLR wheelset, which can easily run a 28mm tire. I also run them tubeless, as they are a full tubeless rim setup, which is why they are awesome. no rim tapes or anything needed. Just put on a tubeless compatible tire, add sealant, and you are good to go :)
TT's and triathlons, 23/25 mm front and 25/28 mm rear, depending on rim width, weight, road surface, frame clearance, brake clearance, and speed. Pressure according to road surface. Don't ride too low of pressure due to potential pinch flats. Yes, you can pinch flat a tubeless tire, and you are screwed unless you have a tube, etc, to deal with it.
I made the leap last year. I now run 28mm tubeless tyres on 25mm internal width hookless rims, 55psi front & 60psi rear, super fast and super plush!
Well done James on doing a very complex subject justice, while still keeping it simple and understandable.
Thanks Andrew, James always smashes the tech content! 🙌Do you ride wider tyres?
- Any bike tech question
- Well... it depends...
That's one thing I don't really appreciate about the biking, honestly. Sill, I can ignore most of it and enjoy my old bike with no pretense on being a top performer so... everyone's happy. 😉
Just keep pedalling on 🙌 Great to hear that you just love getting out on your bike!
Silca has a nice free tire pressure calculator for anyone wondering.
This is so useful information. Specifically the part about matching tyre width with rim width. I bought a bike with carbon OEM wheels that optimised for 25mm. Now I know I can try 28mm on the back but not on the front. Great content.
I have been tossing about changing my rear tyre to 28mm. Currently I am running 25mm on both.Thanks for answering that question. I is a yes.
Ride what is comfortable for you and you will be faster.
I ride 28 I won’t go back to skinnier.
Great vid, with way more nuance than most discussions on this topic!
One of the best and informative "tech" videos this year......thanks very much James for the clear explanations .....👏👏👏
Skinnier for front, wider for rear, best of both worlds aero and comfort
Nice video. GCN also did some experiments and found thinner is faster for same power (for multiple power levels I think too)
Only in labs. In the real world it's the opposite, given that you adjust the tire pressure to match the width and volume.
@@panzervepsI believe the experiment they did was on real roads
I rewatched the GCN video, and they compared 28 to 32mm tyres, and found no difference at 30 kmh, but an advantage for 28mm tyres at 40 kmh.
I note they were running this test on some 26mm wide external rims, which are not aerodynamically suited to either 28 or 32mm tyres.
There are plenty of modern rims with 30-31 mm external width rims which are aero with 28 mm tyres. Finding wheels which are aero with 32mm tyres is a lot harder.
well explained, without promoting the propaganda of wider tires= always better (just because the industry is going that way now, same with the disc brake propaganda). GCN does just that...
Do tires of different widths really have the same rolling resistance? Or is it the lightly taller profile of the wider tires that is not taken into account when calculating rolling resistance, and thereby giving an edge to wider tires?
Lest we forget the turbo encabulator and rotor trunnions !
I am about 85kg (+/- 2 kg depending the time of the season). On my TT I have 23mm front and 25mm back. My wheels are 25mm outside width so the 23 in the front fits nicely. In the rear i think 25mm is as big as i can fit on my 2016 cervelo p3. Haven't really played with 28mm yet but can't possibly see me fitting 28s in the rear. On my road bike (older bike maybe 2010-2012) I can't fit anything bigger than 23mm on the back (It will rub during hard cornering, I tried it). Then i have my waaa bike.... the one i use when its nasty out or towing the kids... that one has 32 all around and feels pretty nice (this bike is an older schwim flatbar converted to drop bar as i upgraded my other bike...)!!
Great video, thank you James! You indicated a higher tire pressure is generally faster due to a higher casing tension (all else equal). Intuitively this makes sense but I know there’s been a recent trend towards lower tire pressure. I’m wondering what the science behind that trend is - I think it’s surface area?
It's implied on the video. It's because rolling resistance isn't the only energy loss. There is aerodynamic losses (also explained) but also vibration losses (hinted behind "comfort" but there's more to that).
Vibration is an actual energy loss, it's not just a problem of comfort. Vibration is forward kinetic energy transformed into vertical kinetic energy (through small oscillation) that is then absorbed by the rider causing fatigue and by the bike causing heat.
When only focusing on pure rolling resistance, we tend to over-inflate. If we want to minimize all the losses, it's better to soften a bit the tyre, causing a bit more rolling resistance but far less vibration loss. The sweet spot depending on the average "bumpy-ness/roughness" expected on the ride.
The "sudden discovery" that rolling resistance isn't everything even performance-wise is the reason we start to go wider, even on pro peloton. To be able to ride a bit softer (optimize overall losses not just rolling) and keeping the same safety margin from pinch flat punctures.
@@nounours2627 thank you for the helpful explanation!
Thank you.
Excellent video 🤘
They said that the tire should be 2 to 4 mm narrower than the wheel. What is the loss on a tire that is exactly the same width as the rim?
Not much I think - it's more about having a smooth wheel to tyre interface. It gets much worse if the tyre's significantly wider than the rim. And this doesn't matter too much for shallow rims
@@themindgarage8938 Does not matter at all for shallow rims. At least does no negate the wider tires advantage. I estimated it on long descends with 23 - 25 - 28 mm tires. The 28 are faster and wider than rims. The 23 were "junk" stock and slowest, the others same model.
I am not sure that "4 mm narrower" tires would aid to the aero advantage. But who knows? May be the dense air pocket will form and help?
24 August 2023
No
Thin tyres harder pressure equals faster it’s a fact, don’t fall for the industry shite, oh I’m a team mech 20yrs, the cycle industry are just a money machine, stop them.