Squared vs rounded tyre profiles

What do you like?

I mounted a Michelin Wild Enduro Front on a 30mm rim and noticed it looking very squared off compared to other tyres I’ve had. At the opposite end of the spectrum is my rear tyre, a Schwalbe Tacky Chan which is very rounded. I haven’t died yet.

Found a few articles discussing it, mainly this one. I’ll try and summarise what I learnt – Squared loads the edge knobs sooner so has more initial bite at lower lean angles, or in flat corners. Rounded is more predictable at the limit of grip or at high lean angles, as it’ll feedback and drift rather than let go abruptly. Rounded is meant to feel more agile and reactive, whereas squared is more stable and predictable. Tyres for soft wet or low grip conditions tend to be squarer than those for drier or hardpack conditions.

From roundest to squarest of what I had to hand I reckon it’s Tacky Chan, Dissector, DHR2, Kryptotal Fr, Kryptotal Re, Wild Enduro Front

For the stuff I mostly ride I like a more square profile; this tends to be slower, steeper, more technical and awkward trails rather than fast and flowing. I’m happy with the compromise for the fast stuff.

Squarer tyres are great for softer conditions, those Michelin corner knobs will dig in amazingly in loam.

Rounder tyres can feel more predictable in firmer conditions, especially loose-over-hard.

The WE front is great in softer conditions, but also fine on hardpack. When you push hard though the corner knobs on hardpack it makes a brbrbrbraaaaaaap noise. I find that quite reassuring as it tells me I am pushing hard enough. Rounder tyres don’t make that noise.

Halfway?

The curve of a rounded tyre does not need to be a constant radius…so a nice flatter section, curving off to chunky side knobs please.

As above really –

Softer/Wetter = More edge and shoulder

Harder packed / Drier =  More rounded profile

My Maxxis Shorty’s and Forekasters have much more shoulder edge and squarer shape than my DHR’s and Rekons.

This review agrees, great UK winter tyre https://bikerumor.com/review-michelin-wild-enduro-front-and-rear-specific-tires-w-gum-x3d-compound/

The WE front is great in softer conditions, but also fine on hardpack. When you push hard though the corner knobs on hardpack it makes a brbrbrbraaaaaaap noise. I find that quite reassuring as it tells me I am pushing hard enough. Rounder tyres don’t make that noise.

When doing that I found it needed more pressure than other tyres to not burp sealant, even with a Rimpact installed. That’s consistent with how easy they were to fit, sidewall was very supple. Another factor for the noise might be how the big gaps between the side knobs.

Halfway?

The curve of a rounded tyre does not need to be a constant radius…so a nice flatter section, curving off to chunky side knobs please.

That’s basically what all the more rounded ones are – Tacky Chan, Dissector, DHR2.

I think about tyres way too much and I’m sorry to say that I’ve never really thought about this aspect. However I’ve had a look at the bike I was riding tonight and the bike I was riding earlier today and I think I’m tending to run a rounder cut-spike style tyre at the front and a squarer intermediate tyre at the back, but they’re not that far apart in shape. The front tyres are a Magic Mary 2.35 (older casing) and Hillbilly 2.6 and the rear are an Eliminator 2.3 and Butcher 2.3, all on 30mm rims.

I think I like front tyres like this because although you have to lean them a fair way to engage the side knobs the centre knobs are good at both cornering and braking, unlike say a DHR2 whose centre knobs stop but don’t turn or a DHF which is vice versa.

My local trails are rarely hero dirt and never loose loam, they’re either loose over hard or slippery mud and roots, depending on the weather.

I don’t think I like really squared off tyres as you tend to have to lean them a lot to get the edges biting in. That’s fine when you’re in the zone and confident but when you aren’t and you go into something a bit tentative there’s less grip.

That said I liked the 2.4” front Wild Enduro Magi-X on a 30mm rim whilst it lasted. Probably only got 3 or 4 months out of it before the knobs were looking really undercut and mangled. Managed to get it warranty replaced and sold the new one on. I’ve never done that to a front tyre before – I’m not a heavy rider and mostly not on aggressive trail surfaces.

People are considering that’ll it’ll look totally different at the contact patch, right?

I don’t think I like really squared off tyres as you tend to have to lean them a lot to get the edges biting in

Surely it’s the opposite?

People are considering that’ll it’ll look totally different at the contact patch, right?

Yep. There were a few remarks about this in the linked article.

Surely it’s the opposite?

Id love to know for sure as I’m not a confident leaner and was bitten by a High Roller many years ago and have since defaulted to rounded tyres.  I am a “confidence” rider though so if modern tyres have evolved to take account for low lean angles yet greater edge grip at the same time to provide greater confidence up front I’d be up for a square edge XC race recommendation different to a Barzo.

Surely it’s the opposite?

A rounder profile tyre will have more consistent grip as it’s leaned through diffferent angles.

A more square profile tyre can feel best if you lean it aggressively and push the edge blocks into the ground.

I’ve just gone back to a WTB Verdict on the front, a pretty square tyre which feels amazing – and which the new Maxxis HR3 seems suspiciously similar to.

A more square profile tyre can feel best if you lean it aggressively and push the edge blocks into the ground.

I’m not following. I’d reason that the edge blocks on a squarer tyre begin to load up at lower lean angles. This is echoed by remarks in the article I linked in the OP.

But squared profile means you can get beyond the bite point more easily and you’re eating dirt without a warning

Yep I’d be more hesitant about squared tyres for fast or bike park stuff where you’re riding more dynamically and pushing on a bit.

I like square-ish, it’s not so much better or worse, I just find it tons more confidence inspiring and tbf that’s the msot important thing a tyre can do at my sort of level, no use in grip that you don’t use because you don’t trust it. Not super square mind you, just the square side of the middle.

In the end I think the individual tyre is more important though.

I’m not following. I’d reason that the edge blocks on a squarer tyre begin to load up at lower lean angles. This is echoed by remarks in the article I linked in the OP.

I’m not talking about specific lean angles, just that a squarer tyre gives you more of an edge to work with – especially on soft ground.

Yep I’d be more hesitant about squared tyres for fast or bike park stuff where you’re riding more dynamically and pushing on a bit.

Yes, I suggested that three weeks ago, thinking about bike park kind of trails:

Rounder tyres can feel more predictable in firmer conditions, especially loose-over-hard.

blackhatFree Member
But squared profile means you can get beyond the bite point more easily and you’re eating dirt without a warning

I’ve found this with a few tyres – a 2.3” dhr2 on the front wheel and a 2.3” Butcher T9 – also on the front wheel. Felt good for grip until the moment it didn’t and I was lying on my face taking soil samples with my teeth.

I’m much happier with a more gradual loss of traction which you seem to get when tyres are more rounded.

Rear tyres I’m less bothered about the profile of.