Folding tyre sidewalls

[jorgemartin]

Hello,


are the folding tyre sidewalls weaker than sidewalls on wire bead tyres?

Cheers

 

[jorgemartin]

Sidewall blowing up under heavy load?

 

[brockers]

To answer the OP's question. No. The wired and kevlar (folding) versions of any particular tyre are made from the same kinds of pixie dust.

 

[accountantpete]

Nope - but you can get folders with sturdier sidewalls than other folders if you are at all worried.

 

[RecordAceFromNew]

Sidewall blowing up under heavy load?

Iirc I read tyres are tested to 2x maximum pressure listed on the tin without blowing, so I would have thought if a tyre hasn't been over-inflated, over-heated, damaged, etc. and is installed on an appropriate sized modern rim an increasingly heavy load is going to cause pinch flat first, since the increase in pressure up to that point must* be relatively modest and still be within the safety margin.

* all else being equal halving the volume is required to double the pressure

 

[jorgemartin]

I've read this 3 times and can't really understand. Would you mind rephrasing or expanding a bit? Thanks!

Iirc I read tyres are tested to 2x maximum pressure listed on the tin without blowing, so I would have thought if a tyre hasn't been over-inflated, over-heated, damaged, etc. and is installed on an appropriate sized modern rim an increasingly heavy load is going to cause pinch flat first, since the increase in pressure up to that point must* be relatively modest and still be within the safety margin.

* all else being equal halving the volume is required to double the pressure

 

[jorgemartin]

How do I know which folders have sturdier sidewalls?

Nope - but you can get folders with sturdier sidewalls than other folders if you are at all worried.

 

[jorgemartin]

Not that I'm aware of...

Has it taken any damage from a rubbing brake block, or a cut from a stone or road debris?

 

[Herzog]

How do I know which folders have sturdier sidewalls?

I really wouldn't worry about it.

Get a decent tyre made by a reputable maker and, providing you don't go massively over the max pressure value, it'll be fine (unless it's a dodgy batch of course... but I think that's a whole new thread)

 

[RecordAceFromNew]

I've read this 3 times and can't really understand. Would you mind rephrasing or expanding a bit? Thanks!

I believe your concern is the tyre blowing up under heavy load.

Under heavy load, the tyre and tube will be depressed, and the contact patch at the ground will increase in size. Eventually the rim will pinch the tyre and in particular the tube as it gets too closer to the kerb/ground/rock, causing a pinch flat, which is not uncommon. I am pretty sure the vast majority of punctures are either caused by sharp foreign objects or pinch flats, while tyre/tube blowing up is rare.

I am not sure if looking for a tyre with "sturdier" side wall is the way to address that - performance tyre manufacturers take pride in offering supple side wall to reduce rolling resistance, I have not noticed any manufacturer advertising how "sturdy" their tyres' side walls are or indeed how to measure that. Imho the way to handle heavy load is to pick a tyre that a) is larger, or failing that b) can take higher pressure and pump it up to such pressure.

 

[jorgemartin]

Great explanation and very useful link to choosing the right tyre. Thanks!

Imho the way to handle heavy load is to pick a tyre that a) is larger, or failing that b) can take higher pressure and pump it up to such pressure.

 

[jorgemartin]

Regarding the tyre that blew up, I just had this realisation. I was using a 47 mm (1.85inch) wide tyre while the rim was too narrow: 22 mm. First I got pinch flats and then the sidewall ripped. Does this make sense?

 

[RecordAceFromNew]

Regarding the tyre that blew up, I just had this realisation. I was using a 47 mm (1.85inch) wide tyre while the rim was too narrow: 22 mm. First I got pinch flats and then the sidewall ripped. Does this make sense?

If the original pinch flats were caused by heavy load on an under-inflated tyre then the tyre sidewall could also have been damaged. Rims are reasonably tolerant of different tyre widths, some suggestions are at the bottom of this page.

 

[jorgemartin]

I was riding a 47 mm wide tyre on a 16 mm rim. According to the chart, that's very far from the safety margin... and this I presume is what happened to me. A too wide tyre in a too narrow rim plus air pressure and heavy load playing a part too. The tyre was 5 days old...

 

[RecordAceFromNew]

To stop it happening again, for road I would suggest look up the graph in the chart here and see what pressures you need to apply front and back of widths you want, then select tyres of whatever make/model/feature/price that can take those pressures.