Tire chat (nerds only)

7/22/2026 12:46am
AndehM wrote:
The Specialized take on radial seems more like what I want, except that the 2 current tread patterns don't appeal to me, and the casing is...

The Specialized take on radial seems more like what I want, except that the 2 current tread patterns don't appeal to me, and the casing is really freaking heavy.  Cannibal / Hillbilly would be intriguing.

Cannibals, my favourite summer tyre are on sale in the uk for £22 (less than half price)at the moment which makes me wonder if they are clearing stock ready for a refresh

6
7/22/2026 5:34am
AndehM wrote:

Shredda Front it looks like.

https://www.schwalbetires.com/GRAVITY-PRO-Shredda-F-Radial-11654553.01

Amaury ran them on that amazing mudder race a few years ago where he won by some crazy margin.

Beat me to it. I'd wager they've been on every single podium for years.

It's a cut Dan - that's the only one with the weird dew claw knobs outside the regular knobs.

Good eye! I didn't notice the claw knobs. I believe Amaury was also on a cut Dan during his winning run in Val di Sole 24:

Screenshot 2026-07-22 at 14.29.30

As it stands, I don't believe radial tires have made it onto a DH podium (or even a practice/quali run for that matter unless anyone knows otherwise?)

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1
1 day ago Edited Date/Time 1 day ago

Beat me to it. I'd wager they've been on every single podium for years.

It's a cut Dan - that's the only one with the weird dew claw knobs outside the regular knobs.

Good eye! I didn't notice the claw knobs. I believe Amaury was also on a cut Dan during his winning run in Val di Sole 24:As...

Good eye! I didn't notice the claw knobs. I believe Amaury was also on a cut Dan during his winning run in Val di Sole 24:

Screenshot 2026-07-22 at 14.29.30

As it stands, I don't believe radial tires have made it onto a DH podium (or even a practice/quali run for that matter unless anyone knows otherwise?)

Well from team muc off atleast Amaury have been running radials for the past two years, Myriam and the Alran brothers maybe less than that. So there is plenty of podiums. I'd bet that even the Dan he was using is an radial tyre.

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pejzaż
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I'd like if someone with actual insider info can comment but my impression is that radial casings are not used much at all in WCDH, certainly nowhere near 'on every podium'. The only time I've actually seen a radial Tacky Chan was on Reece and Hattie's bikes in South Korea. Never seen one on a commencal. I'm not 100% on whether the fronts are sometimes radial but the fact that everyone is using cut Dans very frequently with "no plans to release a radial Dirty Dan" makes me think probably not.

IMO a radial casing in the rear at WC speeds on most tracks would be completely ridiculous. Not as sure for a front tire because they work up to my skill level but I have to imagine they are loading the front a great deal more than I am

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AndehM
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I put my radial Trail TCs back on after having reverted to HR3 EXO+/ DHR2 DD for a few weeks. Jesus, the squirm/vagueness in the back is sketchy AF. I had forgotten just how weird the radial Trail is in the back. The rear just felt like it was wandering all over when climbing, and then randomly steps out in corners before catching (especially flat corners). Lots of grip, then zero and rapidly sliding, then tons of grip again. For some reason, it doesn't do that on the front for me. It's like the sensation of the dead zone a tentative rider gets with a DHF, but in the back... really strange. I was running 22.5 psi front, tried 25.5, 26.5, 26.0 rear (compared to my Maxxis pressures of 19.5/22.5). I think I've gotta run a normal tire in the rear. Time to see if anyone local wants to swap some Maxxis or Conti with me.

I think the Trail is fine for a front casing for weekend warriors, but it's just too soft in the rear unless you're really going slow or riding very soft dirt all the time.  I didn't notice most of this sensation in the rear when I ran Gravity (other than the weird step-out in corners).  I have a theory the step-out comes from running a higher pressure, so that when you unweight the rear a little, it snaps back to full round shape and lose grip until it gets weighted and deformed again.  It's hard to explain the sensation - it's quite different from the usual DHR lateral drift where you can feel the tire dragging on the ground but not digging in.  This feeling comes on all of the sudden, without much if any of the lateral slide feel.  I've had several cases where it happens and all of the sudden the front is oversteered pointing back across the trail, then I have to correct back in the opposite direction.

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TEAMROBOT
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1 day ago Edited Date/Time 1 day ago

Beat me to it. I'd wager they've been on every single podium for years.

It's a cut Dan - that's the only one with the weird dew claw knobs outside the regular knobs.

Good eye! I didn't notice the claw knobs. I believe Amaury was also on a cut Dan during his winning run in Val di Sole 24:As...

Good eye! I didn't notice the claw knobs. I believe Amaury was also on a cut Dan during his winning run in Val di Sole 24:

Screenshot 2026-07-22 at 14.29.30

As it stands, I don't believe radial tires have made it onto a DH podium (or even a practice/quali run for that matter unless anyone knows otherwise?)

Amaury was on radials when he won at Val di Sole in the rain and mud, which I guess means he was on radial Dans? Definitely not a production tire.

Update: and he won on Schwalbe radials at Les Gets that same year. Source: the Schwalbe radial page on their website.

"Amaury Pierron made a brilliant comeback this year after his return. With our radial tires, he won in Val di Sole by almost 5 seconds and in Let Gets by well over 6 seconds - an eternity in racing!"

One caveat: Only Schwalbe knows what was really inside the casing of Amaury's tires at those two races, so I'm going on their word here.  Entirely possible they were stock casings or a completely different third casing we've never heard of with "radial" slapped on the side.

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AndehM
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Is the Shredda Front essentially a cut Dirty Dan in Radial casing then?

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aaronufl
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1 day ago Edited Date/Time 1 day ago

It's a cut Dan - that's the only one with the weird dew claw knobs outside the regular knobs.

Good eye! I didn't notice the claw knobs. I believe Amaury was also on a cut Dan during his winning run in Val di Sole 24:As...

Good eye! I didn't notice the claw knobs. I believe Amaury was also on a cut Dan during his winning run in Val di Sole 24:

Screenshot 2026-07-22 at 14.29.30

As it stands, I don't believe radial tires have made it onto a DH podium (or even a practice/quali run for that matter unless anyone knows otherwise?)

TEAMROBOT wrote:
Amaury was on radials when he won at Val di Sole in the rain and mud, which I guess means he was on radial Dans? Definitely...

Amaury was on radials when he won at Val di Sole in the rain and mud, which I guess means he was on radial Dans? Definitely not a production tire.

Update: and he won on Schwalbe radials at Les Gets that same year. Source: the Schwalbe radial page on their website.

"Amaury Pierron made a brilliant comeback this year after his return. With our radial tires, he won in Val di Sole by almost 5 seconds and in Let Gets by well over 6 seconds - an eternity in racing!"

One caveat: Only Schwalbe knows what was really inside the casing of Amaury's tires at those two races, so I'm going on their word here.  Entirely possible they were stock casings or a completely different third casing we've never heard of with "radial" slapped on the side.

This is where I'm at with radials these days. They are great in a specific use case (like our PNW winters) but outside of that I prefer standard casings. 

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TEAMROBOT
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AndehM wrote:

Is the Shredda Front essentially a cut Dirty Dan in Radial casing then?

Very similar tires, but still come from different molds. This is like one of those "spot five differences between the two images" challenges in kid's magazines:

Schwalbe Dirty Dan Super Gravity 27.5 Tire | Jenson USA

owl-x
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backhanded attacks all day in here. First it’s the “tentative rider” DHF thing, and now I’m not an adult because I read Highlights mag wtf

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TEAMROBOT
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owl-x wrote:

backhanded attacks all day in here. First it’s the “tentative rider” DHF thing, and now I’m not an adult because I read Highlights mag wtf

No one's saying you're not an adult, you're just "young at heart."

Remember in the movie Billy Madison, when Ms. Lippy read the story "The  Puppy who Lost His Way." Well, todays version of that story is about this  guy. He lost his way

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johann377
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Does anybody know what tires Reece Wilson was running during his second place finish at Andorra?Watching his GoPro footage, it looks like he is running a...

Does anybody know what tires Reece Wilson was running during his second place finish at Andorra?

Watching his GoPro footage, it looks like he is running a Shredda and during pre-race interviews I think he said he was running a spike.

Screenshot 2026-07-21 at 18.17.33.png?VersionId=ajqz 6HoGma28uZqWaNpkm

I ask because I'm curious if radial casings have made it to a DH podium.

AndehM wrote:

Shredda Front it looks like.

https://www.schwalbetires.com/GRAVITY-PRO-Shredda-F-Radial-11654553.01

Amaury ran them on that amazing mudder race a few years ago where he won by some crazy margin.

Beat me to it. I'd wager they've been on every single podium for years.

Were Jordan and Finn running the radial Specialized tires during their wins this season? Can't find anything about it now that I went through the old pit bits. 

1
1 day ago

Idk whats going on in this forum lately. 

 

Amaury: I'm using radials. 

Schwalbe: our riders are all using radials. 

 

Us: no one's using radials. 

 

My personal experience, riding them in every condition imaginable, including snow: the biggest improvement in mountain bike technology since we figured out 64 degree HTA could apply to non DH bikes.

 

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Friday
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Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a double down tire I fully cracked my wheel. Are most of yall running inserts, or are the i9 aluminum trail wheels just junk? 

Any opinions on the AL MK4 Flow rim? 

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seanfisseli
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Friday wrote:
Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a...

Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a double down tire I fully cracked my wheel. Are most of yall running inserts, or are the i9 aluminum trail wheels just junk? 

Any opinions on the AL MK4 Flow rim? 

Always look at rider weight when looking at tire pressure. Nino Schurter weighs 150 lbs. he can get away with 17psi. I weigh 200. I cannot get away with 17psi.

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ColinL
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22 hours ago
Friday wrote:
Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a...

Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a double down tire I fully cracked my wheel. Are most of yall running inserts, or are the i9 aluminum trail wheels just junk? 

Any opinions on the AL MK4 Flow rim? 

Always look at rider weight when looking at tire pressure. Nino Schurter weighs 150 lbs. he can get away with 17psi. I weigh 200. I cannot...

Always look at rider weight when looking at tire pressure. Nino Schurter weighs 150 lbs. he can get away with 17psi. I weigh 200. I cannot get away with 17psi.

tire carcass matters a lot, also. radials generally need more air than bias ply.

inserts won't save a rim if you have a very hard hit as the spokes are going to give and then the rim breaks, then you're a sad person who was riding too little air pressure for too little gain.

even if you've bought a wheel with lifetime NQA warranty it will get old waiting on replacements, and also expensive if their warranty says rim only and you rebuild the wheel.

me? 84kg, no inserts, 25psi rear for trail only. rocky dh, 28+. zero rear wheels destroyed, and I have broken single spokes a number of times.

AndehM
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Friday wrote:
Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a...

Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a double down tire I fully cracked my wheel. Are most of yall running inserts, or are the i9 aluminum trail wheels just junk? 

Any opinions on the AL MK4 Flow rim? 

I weigh <155 lbs and local trails don't have many rocks.

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AndehM
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Idk whats going on in this forum lately.  Amaury: I'm using radials. Schwalbe: our riders are all using radials.  Us: no one's using radials.   My personal experience, riding them in...

Idk whats going on in this forum lately. 

 

Amaury: I'm using radials. 

Schwalbe: our riders are all using radials. 

 

Us: no one's using radials. 

 

My personal experience, riding them in every condition imaginable, including snow: the biggest improvement in mountain bike technology since we figured out 64 degree HTA could apply to non DH bikes.

 

If you look at the hot patch of the Schwalbe sponsored pros, they almost never include the "Radial" text.  Another telltale sign when they run "diagnonal" tires is the tread pattern of the Tacky Chan is different in diagonal vs. radial.  I've seen them running radials more often in Enduro but big guys like Richie are never on radials.

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22 hours ago
Friday wrote:
Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a...

Bit of a thread de-rail, but I keep seeing people running like 22 psi in the rear wheel. Last time I tired 24 PSI on a double down tire I fully cracked my wheel. Are most of yall running inserts, or are the i9 aluminum trail wheels just junk? 

Any opinions on the AL MK4 Flow rim? 

There is a lot of factors, and I can't comment on that rim.  That said I've found the Wolftooth calculator to be an accurate tool for me and simplifies it.  It takes into account the bike weight, casing and type of riding.  For me I err on the side of caution and put in "enduro, steeps, rocks" for my riding conditions as I live in Colorado (its rocky) and I enjoy pulling for the blind double last minute and sometimes it doesn't work (dumb lines).  If your denting rims you need to up the pressure, even 1-2 will do a lot.  If you don't like that pressure, up the casing.  I wouldn't worry about inserts.  When I ran them (I don't now) I dented more rims than ever as I thought "oh I can run less pressure", but then I would end up with slashes anyways and carrying a messy pool noodle on the trail and swearing at it installing the repaired or new tire. 

The tool for me changes my Enduro bike from 25 psi with (enduro) riding conditions to 19 with XC/Trail Soft.  (thick casing, 192 total gear weight).  I would never go that low, and have found at lower pressures on tracks that are fast with catch berms the tire roll is no good or I burp the tire.  If it is an all natural, slower non rocky trail sure, but I don't like those trails.  And it basically says I would need to run 2-3 PSI with thin casing, which probably sounds right.  

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aaronufl
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Idk whats going on in this forum lately.  Amaury: I'm using radials. Schwalbe: our riders are all using radials.  Us: no one's using radials.   My personal experience, riding them in...

Idk whats going on in this forum lately. 

 

Amaury: I'm using radials. 

Schwalbe: our riders are all using radials. 

 

Us: no one's using radials. 

 

My personal experience, riding them in every condition imaginable, including snow: the biggest improvement in mountain bike technology since we figured out 64 degree HTA could apply to non DH bikes.

 

I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best choice for someone depends on a number of factors. In the summer when I'm hitting higher speeds I just prefer the support of a standard casing. In the winter when things are wet I find the radials work better because I need all the compliance/grip I can get. Horses for courses.

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ColinL
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aaronufl wrote:
I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best...

I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best choice for someone depends on a number of factors. In the summer when I'm hitting higher speeds I just prefer the support of a standard casing. In the winter when things are wet I find the radials work better because I need all the compliance/grip I can get. Horses for courses.

pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation has a cost, after all.

and DH pros are trying to go faster.

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TEAMROBOT
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aaronufl wrote:
I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best...

I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best choice for someone depends on a number of factors. In the summer when I'm hitting higher speeds I just prefer the support of a standard casing. In the winter when things are wet I find the radials work better because I need all the compliance/grip I can get. Horses for courses.

ColinL wrote:
pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation...

pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation has a cost, after all.

and DH pros are trying to go faster.

Could you please share links for where people have tested the rolling resistance of radial tires vs bias ply? Haven't seen that yet.

storm.racing
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16 hours ago
aaronufl wrote:
I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best...

I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best choice for someone depends on a number of factors. In the summer when I'm hitting higher speeds I just prefer the support of a standard casing. In the winter when things are wet I find the radials work better because I need all the compliance/grip I can get. Horses for courses.

ColinL wrote:
pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation...

pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation has a cost, after all.

and DH pros are trying to go faster.

TEAMROBOT wrote:

Could you please share links for where people have tested the rolling resistance of radial tires vs bias ply? Haven't seen that yet.

Sources are for squares. This is 2026 Robot.

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Evil96
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16 hours ago
aaronufl wrote:
I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best...

I'm not saying no one should use them. I'm just saying like everything else they have pros and cons so whether or not they're the best choice for someone depends on a number of factors. In the summer when I'm hitting higher speeds I just prefer the support of a standard casing. In the winter when things are wet I find the radials work better because I need all the compliance/grip I can get. Horses for courses.

ColinL wrote:
pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation...

pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation has a cost, after all.

and DH pros are trying to go faster.

TEAMROBOT wrote:

Could you please share links for where people have tested the rolling resistance of radial tires vs bias ply? Haven't seen that yet.

I believe it’s the enduro mag test of tyres 

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ColinL
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ColinL wrote:
pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation...

pretty sure that every time radials have been tested against bias ply they do in fact roll slower. the additional surface area contact and carcass deformation has a cost, after all.

and DH pros are trying to go faster.

TEAMROBOT wrote:

Could you please share links for where people have tested the rolling resistance of radial tires vs bias ply? Haven't seen that yet.

Evil96 wrote:

I believe it’s the enduro mag test of tyres 

that's the easiest one to find. magic mary was tested in ... 4 variants, I think?

https://enduro-mtb.com/en/mtb-tire-test-weight-rolling-resistance-punct…

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AndehM
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TEAMROBOT wrote:

Could you please share links for where people have tested the rolling resistance of radial tires vs bias ply? Haven't seen that yet.

Evil96 wrote:

I believe it’s the enduro mag test of tyres 

ColinL wrote:

that's the easiest one to find. magic mary was tested in ... 4 variants, I think?

https://enduro-mtb.com/en/mtb-tire-test-weight-rolling-resistance-punct…

That's the one.  It was even done in Schwalbe's own lab using their equipment.

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TEAMROBOT
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Evil96 wrote:

I believe it’s the enduro mag test of tyres 

ColinL wrote:

that's the easiest one to find. magic mary was tested in ... 4 variants, I think?

https://enduro-mtb.com/en/mtb-tire-test-weight-rolling-resistance-punct…

AndehM wrote:

That's the one.  It was even done in Schwalbe's own lab using their equipment.

The test methodology in that Enduro MTB test leaves a lot to be desired. They measured the tires' rolling resistance on a steel drum (bad for measuring any tire) and with all tires inflated to the same pressures (which is bad for measuring radial vs. bias ply tires).

Measuring rolling resistance on a large steel drum is like picking tires based on how cool the patch on the sidewall looks. And this section in their article about tire pressure proves that the methodology is whack. They found the same results for all brands of DH tires, too (Conti, Schwalbe, Specialized):

"The biggest surprise in our test came from the MAXXIS ASSEGAI: despite identical dimensions and rubber compound, the DH casing version rolls better than the Doubledown. One possible explanation: the DH casing features a coarser 60 TPI fabric, whereas the Doubledown uses a finer 120 TPI weave. The coarser DH fabric might offer more deformation resistance, causing it to flex less under the set pressure of 1.5 bar – meaning less energy is lost to deformation. However, this “phenomenon” can’t be transferred one-to-one to real-world trail riding: in reality, a DH casing would typically be run at a lower pressure – one of its core advantages. That, in turn, would increase rolling resistance again."

The DH tires measured as lower rolling resistance than the lighter casing tires because on a steel drum the faster tire is the hardest tire. A DH tire with 1.5 bar is harder than a single ply or dual 120 tpi tire, so it's "faster." This is nonsense, for the exact reason listed in the paragraph above.

Are there any radial vs. bias ply tests that don't use a steel drum, or that vary tire pressure to reflect the manufacturer's own recommendations?

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codahale
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A note regarding the Enduro MTB test:

This ensures fair comparisons: every tire undergoes the same procedure under identical conditions — 50 kg wheel load, a tread speed of 20 km/h, and an internal pressure of 1.5 bar.

In freedom units that’s a rider weight of 185 lb, a bike weight of 35 lb, and a tire pressure of 21 psi. With the Schwalbe radials, that’s not just going to roll slow, it’s also going to ride like absolute shit. These kinds of tests are useful for comparing within product families but not between product families. It’s like putting a bunch of forks on a dyno with 75 psi in them and four clicks out on all the knobs or running fuel efficiency tests on cars running on 85 octane fuel -- it’s an attempt to control for confounding factors, yes, but the resulting synthetic model is so far removed from the natural setting that its predictive value craters.

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AndehM
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ColinL wrote:

that's the easiest one to find. magic mary was tested in ... 4 variants, I think?

https://enduro-mtb.com/en/mtb-tire-test-weight-rolling-resistance-punct…

AndehM wrote:

That's the one.  It was even done in Schwalbe's own lab using their equipment.

TEAMROBOT wrote:
The test methodology in that Enduro MTB test leaves a lot to be desired. They measured the tires' rolling resistance on a steel drum (bad for...

The test methodology in that Enduro MTB test leaves a lot to be desired. They measured the tires' rolling resistance on a steel drum (bad for measuring any tire) and with all tires inflated to the same pressures (which is bad for measuring radial vs. bias ply tires).

Measuring rolling resistance on a large steel drum is like picking tires based on how cool the patch on the sidewall looks. And this section in their article about tire pressure proves that the methodology is whack. They found the same results for all brands of DH tires, too (Conti, Schwalbe, Specialized):

"The biggest surprise in our test came from the MAXXIS ASSEGAI: despite identical dimensions and rubber compound, the DH casing version rolls better than the Doubledown. One possible explanation: the DH casing features a coarser 60 TPI fabric, whereas the Doubledown uses a finer 120 TPI weave. The coarser DH fabric might offer more deformation resistance, causing it to flex less under the set pressure of 1.5 bar – meaning less energy is lost to deformation. However, this “phenomenon” can’t be transferred one-to-one to real-world trail riding: in reality, a DH casing would typically be run at a lower pressure – one of its core advantages. That, in turn, would increase rolling resistance again."

The DH tires measured as lower rolling resistance than the lighter casing tires because on a steel drum the faster tire is the hardest tire. A DH tire with 1.5 bar is harder than a single ply or dual 120 tpi tire, so it's "faster." This is nonsense, for the exact reason listed in the paragraph above.

Are there any radial vs. bias ply tests that don't use a steel drum, or that vary tire pressure to reflect the manufacturer's own recommendations?

How would you set it up to be representative?  I know Vital did a rolling resistance test several years ago, but it was rolling down a straight section of asphalt and timing them.  Not sure asphalt is better than a steel drum.  The RojoDH guy posting on this forum does timed laps at a bike park comparing front tires, but that ends up including line choice, etc. and each time it's new tire vs. Assegai.

Schwalbe doesn't even provide any specific guidance on how much higher to run their radials other than a vague statement that riders often run slightly higher pressures than normal.  If the argument is that you can run them higher pressure so that they'd have less rolling resistance, then you'd also trade off some of that added grip.  We've seen lots of posts by users here stating that they increase pressures by anywhere from  5% - 30% from their normal pressures, clearly no hard and fast amount you could assume for testing.

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codahale
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16 hours ago

AOL keyword: Chung method

You pick a track with some nice characteristics -- varied speed, nice saddle shape in the profile -- then set up your bike how you’d actually want to ride it, then ride the track in as repeatable a manner as you possibly can. You take high precision speed and power measurements, then do post-hoc statistical analysis which gives you both aerodynamic drag (which varies superlinearly w.r.t. speed) and rolling resistance (which does not).

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