New Mavic Open Pro

[Brucey]

well in this case they must have done something to have decided not to bother with a disc-brake variant in 24 drilling; with some (most?) front hubs braking loads are borne mainly by just six spokes, which is pretty horrendous. Having seen what I've seen, I'd expect 28 hole disc-brake rims to be vulnerable to cracking, especially if the hub flanges are relatively small.

cheers

[The utility cyclist]

Mavic Pro Exalith 'Haute Route', I reckon about 2.3mm braking surface thickness

[reohn2]

Mavic Pro Exalith 'Haute Route', I reckon about 2.3mm braking surface thickness

If it is it's more than any Mavic rim braking surface I've ever seen,1.3mm would be nearer the mark.

[The utility cyclist]

Mavic Pro Exalith 'Haute Route', I reckon about 2.3mm braking surface thickness

If it is it's more than any Mavic rim braking surface I've ever seen,1.3mm would be nearer the mark.

rookie mistake, incorrect measuring method in the early hours, I'll measure again when I've come to my senses!
Can't wait to try them this winter though and I've just been reading up about woven silicon carbide ceramic materials that is lighter than the solid variant but can handle very high temperatures without deforming. Already used in disc brakes on aircraft and motor racing in solid form, would be very interesting as a wheel rim material impregnated into a carbon rim or used as a singular material as opposed to being simply applied as a process to alu based braking tracks.

[pwa]

If I were buying particularly expensive rims (eg Exalith) in the hope of better life expectancy I would be doing my best to protect them from impact damage on potholes and the like. I'd avoid running tyres at low pressure. I've damaged old style Open Pros by going over something in the road with 25mm tyres at too low a pressure. And yesterday a neighbour of mine was trying to straighten the walls on the rim of a factory made wheel after a similar incident. It would be very annoying to ruin an Exalith rim in that way.

[reohn2]

Mavic Pro Exalith 'Haute Route', I reckon about 2.3mm braking surface thickness

If it is it's more than any Mavic rim braking surface I've ever seen,1.3mm would be nearer the mark.

rookie mistake, incorrect measuring method in the early hours, I'll measure again when I've come to my senses!

I thought it must be,you're normally more thorough than that

..... I've just been reading up about woven silicon carbide ceramic materials that is lighter than the solid variant but can handle very high temperatures without deforming. Already used in disc brakes on aircraft and motor racing in solid form, would be very interesting as a wheel rim material impregnated into a carbon rim or used as a singular material as opposed to being simply applied as a process to alu based braking tracks.

Sounds interesting but I'm think they'll cost an arm and a leg.

[reohn2]

If I were buying particularly expensive rims (eg Exalith) in the hope of better life expectancy I would be doing my best to protect them from impact damage on potholes and the like. I'd avoid running tyres at low pressure. I've damaged old style Open Pros by going over something in the road with 25mm tyres at too low a pressure. And yesterday a neighbour of mine was trying to straighten the walls on the rim of a factory made wheel after a similar incident. It would be very annoying to ruin an Exalith rim in that way.

I regularly hop up and down 20cm hard edged steps on my 36spoke touring rims shod with 37mm Hypers at low pressures without any problems and Im no lightweight these days

[pwa]

If I were buying particularly expensive rims (eg Exalith) in the hope of better life expectancy I would be doing my best to protect them from impact damage on potholes and the like. I'd avoid running tyres at low pressure. I've damaged old style Open Pros by going over something in the road with 25mm tyres at too low a pressure. And yesterday a neighbour of mine was trying to straighten the walls on the rim of a factory made wheel after a similar incident. It would be very annoying to ruin an Exalith rim in that way.

I regularly hop up and down 20cm hard edged steps on my 36spoke touring rims shod with 37mm Hypers at low pressures without any problems and Im no lightweight these days

I've got the same 35/37 Hypers on touring rims and yes, I can be a bit more carefree with those. But with my old style Open Pros and 25mm tyres I just make allowances for their more fragile nature. And I don't run the tyres soft. It's too risky. They make up for it by being faster up hills. Neither is better than they other. They are both good in different ways.

[NATURAL ANKLING]

Hi,
Off the top of my head, IIRC Old Mavic module E2 argent come out at 1.93 mm appx.
I don’t run tires low pressures for obvious reasons simply not worth it.
If you’re like me and still running rim brakes.
I would rather have Robust rims don’t save a few grams, quite common to arrive at re-rimming wheels Only to find rim discontinued New spokes needed, option might be a new wheel.

Not suffered flats on rims Since leaving behind steel rims in my green lanning days..........Discovering Aluminium.

What Pips soggy tires? An old steel frame

[reohn2]

If I were buying particularly expensive rims (eg Exalith) in the hope of better life expectancy I would be doing my best to protect them from impact damage on potholes and the like. I'd avoid running tyres at low pressure. I've damaged old style Open Pros by going over something in the road with 25mm tyres at too low a pressure. And yesterday a neighbour of mine was trying to straighten the walls on the rim of a factory made wheel after a similar incident. It would be very annoying to ruin an Exalith rim in that way.

I regularly hop up and down 20cm hard edged steps on my 36spoke touring rims shod with 37mm Hypers at low pressures without any problems and Im no lightweight these days

I've got the same 35/37 Hypers on touring rims and yes, I can be a bit more carefree with those. But with my old style Open Pros and 25mm tyres I just make allowances for their more fragile nature. And I don't run the tyres soft. It's too risky. They make up for it by being faster up hills. Neither is better than they other. They are both good in different ways.

I think a lot of it it the sort of cycling you do,I'm finding the older I get the less tarmac I like.
I ride some pretty rough gravelly stoney tracks,bridleways and towpaths where anything fragile would leave me walking,so I just don't take that risk,my lightweight wheels/bike days are over in favour of durability,comfort and a go anywhere attitude to cycling.
That's not a criticism of lightweight stuff,if it suits a riding style then that's what's best for it,it just doesn't suit mine.
Disc brakes are another source of friction(sorry)on the forum,but again they suit the kind of conditions I find myself riding in more often than not these days,and where rim brakes end up a sludge mess when I could hear the sludge and grit grinding away at rims in an alarming fashion.
To each his own

[reohn2]

Hi,
Off the top of my head, IIRC Old Mavic module E2 argent come out at 1.93 mm appx.
I don’t run tires low pressures for obvious reasons simply not worth it.
If you’re like me and still running rim brakes.
I would rather have Robust rims don’t save a few grams, quite common to arrive at re-rimming wheels Only to find rim discontinued New spokes needed, option might be a new wheel.

Not suffered flats on rims Since leaving behind steel rims in my green lanning days..........Discovering Aluminium.

The thickest brake track on Mavic rims I've ever measured have been 217's @ 1.6mm their A719's are 1.4mm.
By comparison Sputniks are 1.9mm and wear at a slower rate than Mavics indicating they're a better quality aluminium.

What Pips soggy tires? An old steel frame

That depends a lot on where you ride,old steel frames that are considered comfy on small section HP tyres don't handle rough tracks and trails well.
If the two,compliant steel frame/big supple rubber,are combined that's another matter

[Gattonero]

...and after 11 pages no one has yet posted what numbers mean: does anyone have a decent number of rims that have been measured before and after they've failed after the wear on the braking track got the tyre pressure able to crack the rim?

Since wheels can be built different from each other (spoke tension and pattern, to name a few) and used with tyres of different width and pressure, by riders of different weight on much different terrain, I've never really bothered to actually "measure" a rim for its wall thickness.
Having seen people going trough almost any type of road rim in one year -let alone the wear of the brake pads- while there's folks who commute no less than 50 miles a week for many years on the same rims, you see it becomes like the chain wear measurements: the smooth and careful cyclist may ride many many miles on a chain that is slightly worn, while the "angry racing commuter" or the "weekend warriors" or the "Strava obsessed" will wear out a chain and get it to skip in a very short time.
Each to their own

[Brucey]

... I've never really bothered to actually "measure" a rim for its wall thickness....

well maybe you should. The stress in the rim roughly goes with the cube of the thickness; this means that things can go bad very quickly and ever-smaller amounts of rim wear cause much higher stresses in the rim, out of all proportion with the amount of material removed each time. I posted this in another thread but if you want a simple takeaway re braking surface thickness this is one:

If a rim is 'safe'

- at 1.0mm thickness then

-at 0.8mm wall thickness the stress in the rim is doubled (vs the 1.0mm stress) and

-at 0.7mm thickness the stress in the rim is tripled (vs the 1.0mm stress)

cheers

[reohn2]

I reckon(from experience)that below 1mm wall/brake track thickness you're skating on thin ice,below 0.9mm and failure is imminent.

[Gattonero]

... I've never really bothered to actually "measure" a rim for its wall thickness....

well maybe you should. The stress in the rim roughly goes with the cube of the thickness; this means that things can go bad very quickly and ever-smaller amounts of rim wear cause much higher stresses in the rim, out of all proportion with the amount of material removed each time. I posted this in another thread but if you want a simple takeaway re braking surface thickness this is one:

If a rim is 'safe'

- at 1.0mm thickness then

-at 0.8mm wall thickness the stress in the rim is doubled (vs the 1.0mm stress) and

-at 0.7mm thickness the stress in the rim is tripled (vs the 1.0mm stress)

cheers

Field experience says that a tyre at 100psi does not create the same problem of a tyre at 80psi. Let alone the differences in materials, you will be surprised at the strenght of heat-treated alloys.
I'll see if I can get some pictures...