jadmt

Sell them and buy higher rated tires

smd4

You’re only referring to hydrostatic testing. Not design. Even using your calculation, he could run the tires at 62 psi and not worry. Which is, you know, sort of my point.

I thought you had me on your ignore list? Which I considered a great honor. I'd hate to be one of the few people here who isn't on it. Can you please put me back on? This place was much more enjoyable when I didn’t need to hear from you.

pdlamb

This 150% proof test requirement is what I've seen for most pressure vessels, though it doesn't mean design standards won't be higher. The only 400% requirement I know is for small diameter lines and fittings.

DiabloScott

PSNS! I de-commed my sub there. We had a different kind of boiler of course, and we had different certifications, but PVs are PVs.
Bangor/Bremerton was some good duty.

KerryIrons

Which, based on lots of experience on this forum and others, means that it REALLY is NOT common knowledge. Just saying.

urbanknight

Sound advice. My 700x35 Pirelli Cinturatos list a max pressure of 72psi.

ambaal

Normally an excellent idea, but they are already full of sealant, and the place I live isn't exactly a great market for tubeless gravel tires.

I tried running at 60psi and 55psi both. I think i'll stick with 55: there is noticeably less squish and it seems cromulent enough.
Kenda is actually a pretty great tyre: on category 2 gravel/lose hardpack it hold very well, and I like how it rolls too.

I'll probably get a set of Maxxis ramblers in 37c (biggest my frames can fit) and see how that one goes.

grumpus

You can damage the sidewall by pinching it between the rim and a rock, I don't think there's a requirement for it to be an inner-tube that loses air.

ambaal

I would be more concerned with rim damage in such scenario (and probably with a resulting burp or even de-hooking from rim)
Tyre sidewall is considerably more resilient than tube.

ambaal

Ok, it gets interesting - one tyre started to lose pressure fairly rapidly and detached from the rim (while standing, mind you).
Not very sure if it is a tyre failure or dodgy valve (stan's kit valves are very meh), but that is not the plan.

I wonder if excess pressure (i did run it at 60) cause bead to stretch? Anyway, I'll replace valve and see how it goes from there.

grumpus

Regardless of your personal priorities, or how much less likely it is that a tubeless tyre will suffer a pinch puncture, my statement still stands.

davidad

[QUOTE=ambaal;23100463]Hi everyone.

I recently got myself in a fairly stupid situation: i've purchased 2 kits of Kenda Alluvium 700x35c to fit on my gravel and not-so-cyclocross bikes.
Now, by itself nothing wrong with this, but there are two problems:

1. I'm about 125kg/280lbs heavy. Bike is another 10-12kgs depending on how much water i have.
2. Max rated pressure on Kenda Alluvium of any size is 50psi. I didn't check it before buying and it's a non-returnable purchase (they both are also already fitted and with sealant inside anyway).

I run them tubeless, on 17mm and 19mm internal width rims (rims are rated much higher, i used to be riding 75 tubed on 33mm tires before, constant pinch flats below 60). I mostly ride a mix of category 2 gravel and paved roads to get there.

While riding at 50psi seems to be possible (i did couple of rides and nothing bad happened so far), the tires do look like they could use some more air. As in i'm pretty uncomfortable with how much they deform even under static load.
Now, all tyre pressure calculators suggest around 55-60psi. I tried them at 60psi, and it seems like a sweet spot for my weight: good contact patch, good rolling. But it's 10psi or 20% above tyre limit.

I contacted Kenda and their reply was pretty much 'welp bad luck dude, we already have your money nice knowing you'

So, questions I have:
1. Is it OK to go 5-10PSI (that would be +10%-20% above max tyre pressure) above max?
2. Should i be riding on 50psi instead and not bother with tires looking half-flat?

The side wall pressure is an unreliable guide and 1/2 of the pressure needed to blow the tire off of the rim. If 60 in the rear works you can run less in the front because of weight distribution. Less weight on the front wheel allows less pressure and a more comfortable ride.

mikeonbicycle

you need to pump up these wider tires to recomended tire pressures,the tire may not pop but with over inflation the rims can split at the sides,Roger Musson has done a few articles about just that,40 psi is the limit,skinny road rims are made for very high pressures,wider rims are not

ambaal

My rims are rated at least at 90psi, i'm not worried about them in the slightest. I run them with tubes (and different tyres) at 75 for couple of years each, no issues.

My main concern is sidewall blowout. But thinking of it, if casing starts to rupture, it usually forms a bulge first, and seen as I have about 2mm clearance from frame, it probably would be hard to miss.

mikeonbicycle

if that rim states it will handle that pressure than its fine,its allways good to not go way beyond the specs cheers,alot of those earlier single walled rims cant do much over 40 psi,they do split at the rim sidewall cheers

Delmarva

Or just store them and buy higher rated tires.