Rear wheel buckle.

[wafter]

That damage seems very odd - must have taken a lot of force to distort the rim so much, yet there are no obvious impact / abrasion marks in the area of damage while the tyre appears fine and evidently remained inflated.

Was there anything on the inside / bead seat of the rim that might give us a clue as to what happened?

Also, beware ally work-hardening. IME you can often bend stuff back to close to where it started, however this will weaken it and the closer you get to the starting point the more brittle it will become. I had this with the bars on my Routier - the closer to "correct" they got the more the load required to bend them seemed to ramp up exponentially... I suspect if I'd pushed them all the way they'd probably have snapped or perhaps started bending elsewhere.

 

[Binky]

That damage seems very odd - must have taken a lot of force to distort the rim so much, yet there are no obvious impact / abrasion marks in the area of damage while the tyre appears fine and evidently remained inflated.

Was there anything on the inside / bead seat of the rim that might give us a clue as to what happened?

Also, beware ally work-hardening. IME you can often bend stuff back to close to where it started, however this will weaken it and the closer you get to the starting point the more brittle it will become. I had this with the bars on my Routier - the closer to "correct" they got the more the load required to bend them seemed to ramp up exponentially... I suspect if I'd pushed them all the way they'd probably have snapped or perhaps started bending elsewhere.

Yeah it's odd. I'd just crested a short but very steep climb, there was a slight downhill and I braked for a bend after a flat section and was aware something definitely not right. No indication before of issue and I hadn't gone into pothole.
I straightened it out yesterday and had a short 20 mile ride today. It's fine but not perfect and as you say I'm reluctant to do much more with it as aluminium will only take so much before weakening too much.
I'm planning on new bike in a couple of weeks but I'll keep this as back up so I'll aim to source a replacement wheel when a bargain comes around.

 

[SuperGalactian]

That's way too high. It says on sidewall Max 116 psi

All the sizes of the GP5000 have recommended minimum pressures. For those with maximum 116, the minimum is either 85 or 95psi.

 

[Binky]

All the sizes of the GP5000 have recommended minimum pressures. For those with maximum 116, the minimum is either 85 or 95psi.

I suggest you go to Silca or a similar site, enter in total system weight etc and see.
95psi way above requirement.

Also check out various GCN videos on tyre pressure.
From what you are saying I suggest you are probably running your tyre pressure way too high.
Don't take my word for it though, go check.

Also it was wheel rim that got damaged, I didn't puncture and no damage to tyre which would be far more likely if pressure was too low which it wasn't.

 

[C R]

I suggest you go to Silca or a similar site, enter in total system weight etc and see.
95psi way above requirement.

Also check out various GCN videos on tyre pressure.
From what you are saying I suggest you are probably running your tyre pressure way too high.
Don't take my word for it though, go check.

Also it was wheel rim that got damaged, I didn't puncture and no damage to tyre which would be far more likely if pressure was too low which it wasn't.

For the rim to hit something to damage it like that the tyre needs to be squashed enough for the rim and the something to come into contact. Higher pressures make that encounter less likely.

 

[SuperGalactian]

From what you are saying I suggest you are probably running your tyre pressure way too high.
Don't take my word for it though, go check.

OK, I’ve just done that. The Silca calculator suggests 101/102 psi for my everyday bike. I actually use 100 front and back.

However, the calculator doesn’t take into account the specific brand of tyre. As tyres are designed quite subtly, I listen to what the manufacturer advises. For those currently in my stable:
Michelin Pro 87-116 (my everyday bike)
Vredestein Fortezza Senso 115-175
Schwalbe Marathon Plus 60-95
Conti Ride Tour 70- 80 psi

If you choose to ignore the manufacturer and ride on lower psi, it seems to me obvious that you risk rim damage.

 

[Ajax Bay]

I suggest you go to Silca or a similar site, enter in total system weight etc and see.
95psi way above requirement.
From what you are saying I suggest you are probably running your tyre pressure way too high.
Don't take my word for it though, go check.

The Silca calculator suggests 101/102 psi for my everyday bike. I actually use 100 front and back.
However, the calculator doesn’t take into account the specific brand of tyre. As tyres are designed quite subtly, I listen to what the manufacturer advises.
If you choose to ignore the manufacturer and ride on lower psi, it seems to me obvious that you risk rim damage.

@SuperGalactian - we don't know tyre width or system weight of @Binky so you are 'shooting blind'.
100 psi seems extraordinarily high but perhaps you are running 23s and are 16 stone, in which case fine.
Conti suggests a "recommended" pressure for their 5000s. Is this a minima? Imho it's b****x - without specifying load. Maybe they are 'aiming off' for the litigious median 'American' male recreational rider.
70F and 80R here for system load 85kg on 5000 28s,

All the sizes of the GP5000 have recommended minimum pressures. For those with maximum 116, the minimum is either 85 or 95psi.

https://www.continental-tires.com/products/bicycle/tires/grand-prix-5000/

 

[SuperGalactian]

@SuperGalactian - we don't know tyre width or system weight of @Binky so you are 'shooting blind'.
100 psi seems extraordinarily high but perhaps you are running 23s and are 16 stone, in which case fine.

Fair comment. But to me, 65psi for a performance road tyre seems 'extraordinarily' low.

I am on 23x622 and weigh 11 stone. Total weight with steel frame bike is 81.3 kg. Poor paved road surfaces, mid-range tubed tyre, and choose the ride how you like. Try it in Silca and see.

 

[Ajax Bay]

Let's say @Binky is a normal rider (of bike/wheel described) an is rolling on 28x622 and weighs 75kg. Total weight with steel frame bike is 85kg so 40/45 split. Front wheel = 65psi.
Congrats at your steadfastness at maintaining that 23s are best, to hell with the vibes. It used to be that "performance road tyres" weren't made wider than 25mm. They are now! Try some, though I guess you may not have the clearance, with guards.

 

[SuperGalactian]

View attachment 811600

View attachment 811601
Let's say @Binky is a normal rider (of bike/wheel described) an is rolling on 28x622 and weighs 75kg. Total weight with steel frame bike is 85kg so/45 split. Front wheel = 65psi.

What is that graph based on? Presumably theoretical considerations, as there are no data points (and I don’t know what a ‘15% wheel drop’ is.) What would be instructive in the current thread would be data on wheel damage per distance travelled, plotted against tyre pressure - with separate families of data points for each tyre width, of course.

Congrats at your steadfastness at maintaining that 23s are best

I don’t/didn’t. My everyday ride is a steel bike from the 1980s, when, as you say, fast meant narrow. So the rims and clearances don’t allow much deviation. I did once try cramming some Gatorskins in there, but actually I hated them anyway.

I have another road bike on 23s, but also a tourer on 32s. My wife uses 28s on her e-converted hybrid, but I’m planning to switch her to 32s when she next needs tyres. I favour wider tyres increasingly because of our absentee road surfaces. However, for my taste, on good roads they don’t match the feel of a nippy bike on narrow tyres.

I still don’t understand why you believe manufacturers don’t know what they are talking about. Perhaps I’m naïve, but I’m inclined to think there is reason and/or testing behind their recommendations.

 

[Ming the Merciless]

My everyday ride is a steel bike from the 1980s

When 27 x 1 1/4 “ was the norm outside racers. In other words 32mm wide as near as makes no difference.

 

[SuperGalactian]

When 27 x 1 1/4 “ was the norm outside racers. In other words 32mm wide as near as makes no difference.

Are you suggesting they reinvented the wheel?

But actually modern bike tyres are sophisticated items compared with those on roadsters of the last century. And with a price to match - some bike tyres now cost more than a car tyre.