New cracks in tyre wall. Help!

efunc

Hi all,

being relatively new to cycling I haven't encountered this before. I just use this bike for short trips to the shops a couple of times a week, nothing strenuous.

The tyres were new when I bought it a year ago and have been fine. Yesterday however I noticed some cracks in the front tyre wall have suddenly appeared and I'm fairly concerned. Up until then they were fine. Ever since I've had it I've never done anything but ride it, not even pump up the tyres. Last week however I bought a new foot-pump from Aldi though so I thought I'd better top up both tyres for the first time as the rear one was fat. My pocket pressure gauge tells me the rear is now 30psi and the front 40psi. Have I gone too far?? Has this caused the cracks? Is the front now unsafe?!

Pics:

YeehaaMcgee

Cheapie tyres, probably deteriorated due to UV - seen it happen a few times over the years to budget tyres, but I'm not 100% certain what the cause is.

efunc

But it stays in the shed, out of any light. I ride it or tarmac roads about half an hour in the evening, and then it's back in the shed again.

You may be right, however I thought maybe it's no coincidence that I topped up the tyre pressure last week for the first time. I pumped them up until it was getting difficult to pump any more - about 40psi on the front. I weigh about 11-12 stone, so what should the pressure be out of interest?

cooldad

Probably riding them flat - the sidewall folds and cracks.
Time for new ones.
Most people run slightly higher pressure at the back as that's where most of your weight is.
Pressure is a personal thing, but I'm much heavier than you and run 30-35 psi in the rear, 25 -30 psi in the front depending on tyres, terrain etc.

cooldad

Just read you're riding it only on the road. Then higher pressures and maybe get some slick or semi slick tyres.

efunc

cooldad wrote:

Probably riding them flat - the sidewall folds and cracks.
Time for new ones.

Yes, that makes sense about running them flat, that's why I was on an urgent hunt for a bike pump and stopped riding until I had the tyre pumped back up. However it was the rear tyre that was flat. The front tyre is the one with the cracks suddenly appearing, and that was never even remotely flat. the pressure was fine. Maybe I should let the pressure back down to about 30psi.

Are these no longer safe? I'm not doing anything particularly 'off road' with it.

cooldad

I wouldn't use them, faceplanting onto tar if one blows is no fun.
But as Yeehaa said, it happens, doesn't really matter why, it's happened.

YeehaaMcgee

It's your call whether or not they're safe.
If you're playing with traffic at 30mph, or throwing yourself down treacherous trails, you're going to have different criteria (and consequences) to someone who just uses their bike to pootle about.

Nancy Luger

You don't want less air in them, you want more if your riding on tar. I've never seen a tyre damaged like this by being to high. As has been said, too low a pressure has very likely contributed to their state as the tire contorts itself much more easily at low pressures. If you're only using the bike on tarmac to go down the shop and back i'd bin them and get a decent pair of slicks and pump them to a decent pressure.

majormantra

The cracks are probably superficial - i.e. just in the rubber and not through the casing. You can check by removing the tyres.

In any case, if you're riding on tarmac you'll have more fun on slicks as others have pointed out.

efunc

Thanks for all the advice. I primarily wondered why it happened, so that I don't get the same problem again, and if they were still safe for light use.

I intend to buy another bike with hybrid tyres (carrera subway 8), and wanted to keep these chunky ones for trails and canal paths. Anyone have a recommendation for a budget tyre that will at least be safe, if not the best performance?

YeehaaMcgee

I've always got on reasonably well with budget Continentals or Maxxis.

efunc

Oh dear, carrera subway 'eight' appears as subway 8)

Unintended!

paul20v

Tyres look on there last legs in the centre anyway
If it was me i would get them done
As already said falling off isnt fun especially on the black stuff .

IT66T

efunc wrote:

Thanks for all the advice. I primarily wondered why it happened, so that I don't get the same problem again, and if they were still safe for light use.

The usual reason for this happening is normally down to the tyres aging and the rubber drying out so they will no longer stretch like they should and therefore they split and crack as the surface of the rubber becomes brittle and being in dry warm conditions can also cause this .

felix.london

efunc wrote:

My pocket pressure gauge tells me the rear is now 30psi and the front 40psi. Have I gone too far??

The tyres should have manufacturers recommended pressures on the tyre wall, no?

As others have said - if you're only riding tarmac you want to have them at the upper end of this scale.

Northwind

Are those Factory XCs? Bloody awful tyres if they are tbh. Heavy, slow, unpredictable. The cracks may improve them

efunc

felix.london wrote:

efunc wrote:

My pocket pressure gauge tells me the rear is now 30psi and the front 40psi. Have I gone too far??

The tyres should have manufacturers recommended pressures on the tyre wall, no?

As others have said - if you're only riding tarmac you want to have them at the upper end of this scale.

It says 250 - 450 kPa (65 - 65 LBS). Not sure if anyone can translate that :oops:

Chunkers1980

Dunno, but pretty sure google will know the answer.

efunc

Northwind wrote:

Are those Factory XCs? Bloody awful tyres if they are tbh. Heavy, slow, unpredictable. The cracks may improve them

The front one with the cracks is a new'ish Tioga Extreme XC 26 X 2.10. Ridden lightly, always correctly inflated, kept in the shed at all times. Not sure what I've done wrong really. So these should just be avoided at all costs?

Northwind

Well, to be fair they're normally durable, and very cheap. But yeah, they're not good tyres even when they're not unexpectedly falling apart.

YeehaaMcgee

efunc wrote:

It says 250 - 450 kPa (65 - 65 LBS). Not sure if anyone can translate that :oops:

250KPa = 36PSI
450KPa = 65PSI

efunc

Thanks for that.

dhobiwallah

It says 250 - 450 kPa (65 - 65 LBS). Not sure if anyone can translate that :oops:

1 Kilopascal (kPa) = 0.145037738 Psi (Pound Per Square Inch)

"kpa in psi" in google - wasn't that hard :roll:

36 - 65 psi

dhobiwallah

too slow!

cooldad

dhobiwallah wrote:

too slow!

By a day? That's not slow, that's speshul.