Tyre sidewall split/crack

[Dadam]

Just photoing the tyres on my folder to buy the right size tubes and noticed these "cracks" going most of the way round the tyre, both sides. Bike is a Carrera Intercity Disc 9 from Halfords.

Bike (and hence tyre) is 6 months old, less than 50 miles on it. It's not been ridden off road or hard, it's been stored in my garage the whole time. The tyres have never been off the rims and have always been inflated. I just pumped them up the other day (to about 90) as the pressure had dropped a bit. They're rated to 110 psi but to my knowledge have never been pumped above 100.

Is this something to be concerned about?

 

[Dadam]

The photos are both sides of the same tyre. I can't remember if I checked the other one but I will

 

[Cycleops]

Doesn't look good to me. I should return it to Halfords and ask for a replacement bike or tyres.
Bikes are often supplied with budget tyres but those cracks shouldn't be there, even on low cost rubber. Might be an idea to ask for a discount on replacement tyres with better puncture protection as these will likely have none. Perhaps some Schwalbe or Contis.

 

[wafter]

This seems to be a decent tyre pressure calculator that caters for a range of sizes.

90psi sounds a bit much for the size (and your front and rear pressures should be different to reflect their differing loads), however I'd not expect this to damage the tyres - especially given that their rated pressures are around 20% higher.

Often sidewalls are damaged by running at an inadiquate pressure; but this usually manifests as criss-cross delaminations rather than what you're seeing here.

I don't know the brand and I'd be inclined to suggest that the issue is down to manufacturing quality. As it stands I'd not think it to be a safety-critical issue (yet), but it's not ideal and obviously isn't going to get any better. Be concerned when you can see the crack opening up, exposing threads (which in time will break; warning of imminent failure).

Were it me I'd take it back and flag the issue; making sure they're aware that you;re inflating to an appropriate pressure / at least one that's within the tyre's stated max. See what they want to do about it, if they brush it off get as many miles as you can from it then take the tattered remains back and demand a new set of tyres.

 

[Jenkins]

Just checked mine (same bike/tyre combination, approx 150 miles, kept in indoors/shed) and I can't see the same cracking on my tyres. Although you've only owned the bike for 6 months, the tyres may have been sitting around in a factory for some time prior to that awaiting fitting or been fitted to the wheels and left underinflated for a while prior to sale.

 

[Dadam]

@wafter I’ve not personally inflated them beyond 90 but they were pumped up quite hard when I bought the bike and I’ve read quite a few people running Bromptons at 100 or more, so assumed this was common practice on small wheel bikes. 🤷‍♂️
They’re cheap tyres but nearly new ones shouldn’t look that.
I’ll take it in and ask about the tyres but I love the bike and they’ve discontinued this model, so I don’t want to return the whole bike

 

[Emanresu]

This is the manufacturer

https://www.veetireco.co.uk/about-us

This is what they say so follow what they say and take it back to Halfords to complain. Consumer Rights Act 2015 covers it.

 

[wafter]

@wafter I’ve not personally inflated them beyond 90 but they were pumped up quite hard when I bought the bike and I’ve read quite a few people running Bromptons at 100 or more, so assumed this was common practice on small wheel bikes. 🤷‍♂️
They’re cheap tyres but nearly new ones shouldn’t look that.
I’ll take it in and ask about the tyres but I love the bike and they’ve discontinued this model, so I don’t want to return the whole bike

Cool - fair point about the pressure but tbh it's hard to get up to these sort of heights with normal pumps so someone would have had to have made a concerted effort.

Brompton tyres are also typically rated at 110-115psi, but this is a max. safe working limit, rather than a target. I'm currently running my rear at around 100, bit it's significantly smaller and narrower than yours. I'd expect maybe 70-80psi to be more appropriate for yours (rider weight depending) - give the tyre pressure calculator a go.

IMO it's all on the tyres rather than you and would definitely take it back. Doubt they'll want to take the whole bike back and might just change the tyres to minimise the grief... suspect it will largely depend on the individal member of staff you deal with.

 

[Yellow Saddle]

That tyre is just fine. All rubber of the kind used in tyres and tubes stored whilst stressed (such as when folded) will crack in time. However, the rubber on a bicycle tyre is not structural. The tyre's integrity is in the casing - a web of cords spun diagonally from bead to bead. This web contains the air pressure in the tyre and is woven at an angle that shrinks the tyre slightly when inflated, keeping a good hold on the rim.

If the casing is compromised, you'll notice a bulge or a "broken nose" wobble in the tyre's true as it rotates.

Of course cracked and peeling rubber could become an issue. For instance, if it starts to peel off the tread and starts flapping about or, hitting the brakes or such. Other than that, small cracks in the sidewall or tread are of no consequence.

Even when cracks trap grains of sand in the tread, it is of no consequence since those grains will NOT work through the thread. If they don't punch through on the first rotation (like a shard of glass does), then it is harmless.

Go ride, let those tyres live a long and useful life before replacing and save the planet.

 

[fossyant]

As above tyre is fine. Got bigger crack in my commuter tyre near where the main tread to sidewall area is due to the not very flexible puncture protection layer in my Lifeline Commuter tyres. So long as the casing is solid and there is no damage to it or the rubber isn't delaminating then it's ok for this sort of crack on a newish tyre.

 

[I like Skol]

I'm going to sit on the fence between the @Yellow Saddle POV and the OPs concern. The crack shouldn't be there, never used to happen 'back in the day' and seems to be getting increasingly common with current tyres.

I think (suspect) it is due to weight/material saving more than anything else. The sidewalls seem to consist of little more than carcass and just enough rubber to keep it in place. Light tyres = more sales to weight conscious customers (even I use weight as a deciding factor, all else being equal). Less material= lower manufacturing cost/bigger profit potential.

IMO it's not right. The tyre should only develop cracking like that when old and perished. I don't have a problem when it does occur provided the tyre still retains it's shape and there are no other issues.

 

[Dadam]

Thanks all. I pass near the branch I bought the bike on a regular basis visiting my mum and my experience is they were a pretty helpful bunch, unlike some other branches. If I remember I'll put the bike in the boot and pop in with it

 

[Dadam]

Google suggests multiple causes such as age, exposure, over-use, under-use, under-inflation, over-inflation.
None of those is really plausible in this case except under use which tallies with this article (about car tyres but same principle)
https://www.theguardian.com/money/2023/may/27/covid-pandemic-blamed-for-uk-rise-in-cracked-tyres

I assumed they were cheapo tyres but the website suggests an RRP of £39.99!
Plus this nugget:

The honeycomb center tread provides virtually zero rolling resistance

Just checked mine (same bike/tyre combination, approx 150 miles, kept in indoors/shed) and I can't see the same cracking on my tyres. Although you've only owned the bike for 6 months, the tyres may have been sitting around in a factory for some time prior to that awaiting fitting or been fitted to the wheels and left underinflated for a while prior to sale.

What pressure do you keep them at?
Tyre calculator suggests around 68 front and 74 rear for me + bike + stuff.

 

[wafter]

Thanks all. I pass near the branch I bought the bike on a regular basis visiting my mum and my experience is they were a pretty helpful bunch, unlike some other branches. If I remember I'll put the bike in the boot and pop in with it

Cool - IMO the best outcome would be for them to issue another pair of tyres and let you keep these; which you can then run until they actually start to fall apart. In practice since it's potentially a liability issue, if they choose to do anything they'll probably want to replace them themselves and retain the originals..

 

[Yellow Saddle]

I'm going to sit on the fence between the @Yellow Saddle POV and the OPs concern. The crack shouldn't be there, never used to happen 'back in the day' and seems to be getting increasingly common with current tyres.

I think (suspect) it is due to weight/material saving more than anything else. The sidewalls seem to consist of little more than carcass and just enough rubber to keep it in place. Light tyres = more sales to weight conscious customers (even I use weight as a deciding factor, all else being equal). Less material= lower manufacturing cost/bigger profit potential.

IMO it's not right. The tyre should only develop cracking like that when old and perished. I don't have a problem when it does occur provided the tyre still retains it's shape and there are no other issues.

Have a good look at some older tyres. The sidewalls were extremely thin, to the point where the cords were often exposed halfway in their diameter. They were sensitive to UV and tan walls used to crumble, nevermind crack. Back in the day only gets better as our memory fades. Weight saving has nothing to do with it. It has to do with rubber that's stressed (stretched) by folding and time. I'm sure you've seen handlebar gadgets held onto the bar with stretched O-rings where the O-rings routinely crack in situ, but the spare ones in the packet survives several decades without damage.

UV protection has improved as has rubber polymers. Things really are better now than in the good old days.