There are a lot of interesting and useful ways to test blow off pressure. Enough so that it’s probably really important to decide in advance what, exactly, you’re trying to accomplish with the test. Even this isn’t particularly easy.
The ETRTO testing is very limited in scope (and it’s a really low bar, pun intended) but the “hold pressure for 5 minutes” requirement makes a lot of sense to the (many) bike shop folks who have been through the “tire spontaneously explodes off rim on bike in the ‘ready to go’ corral”.
I don’t know, seems no more expensive than what you are doing now. Maybe you could just go up in 5psi increments until the tire pops off the rim?
In any case, your current tests are useful, but it would be interesting to see how high you could go with the tires and rims you are selecting to experiment with.
Im trying my best to avoid pure blow offs as those could do damage to rims… ( expensive ) Mostly at like super high high pressures… I did take the CADEX 25 mm tire up to 140PSI last week… Nothing happened…
Currently for round one of this new toy we have… We are taking everything up to 110PSI at the same speed that someone might do with a floor pump… So we make sure the tire is seated… Then we deflate, Hook it up in the Homemade bomb chamber… Hit record on all the camera’s, put on our ear protection and slowly use our $7.99 gauge and pray nothing blows up…
Today we did,
CADEX 36 WHEEL
Tires
Cadex Race Tire 25mm
Cadex Race Tire 28mm
Conti AERO 111 29mm
Conti 5000 S TR 28mm
Tomorrow we will do a Conti 5000 S TR 25mm
Challenge 29 Strada
Then we will move on ZIPP / ENVE wheels.
So far the only issue we have had is oddly enough is Josh Poertner’s very own ( I wish I was making this up ) SILCA HIRO SIDE-LEVER LOCKING PRESTA CHUCK- CARBON STEEL. Keeps coming off at like PSI 100 so we had to start.
In talking with my studio manager I think our new test is talking things up to 100 PSI then putting it on a KICKR Rollr unit and riding for 5-10 mins maybe pretending to hit a couple of bumps or so…
No 5000 TT?
Are you using sealant for these tests?
No. When asking everyone I have spoken too… no one uses sealant for tire pressure testing…
I have find of them first… Called 4 shops today…
Ok. I think this will be fine for your relative testing (ie if there are differences between wheels/brands. But from an absolute risk thing, noting that IRL everyone is going to have sealant in there, which potentially creates either additional seal (increasing blowoff pressure) or a bobble of sealant that creates a point for a ‘burp of air’ to more easily blow out (reducing pressure to blowoff), which does mean that whilst informative is not something that can be used as directly actionable data.
I note that of course this is exactly in line with what you said you were aiming to do so all good. Just wanted to check.
I have asked that question as well… But I have yet to find a single wheel or tire company that is doing tire pressure test with sealant…
But isn’t that a worry? I mean if no-one has tested what /how we actually ride, then seems a real gap in the testing/safety assessment.
I mean the advice for getting normal tubeless to seat at one time (is it still?) was to pop some washing up liquid on your finger and then run it round the bead. I can imagine that if you did that on hookless and tested that straight after install you’d get much lower blow-off. A week later -not sure. Just use water - again suspect less so and certainly less the longer you leave. So is the advice out there for users to be clear about not using any ‘assistance’ for seating on hookless?
And I’d see sealant in the same way. Do we need to be informed to make sure sealant is only installed via a removable core once the tyre is seated, as opposed to poured down the side of tyre where it would get between rim and tyre.
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I think a lot of that has to do with mostly people trying to do them without a compressor and or big MT bike tires. I just seated 5 tires today with zero issues. changing the tires and seating them has been the fastest and easiest part of the project so far…
Also as far as sealant goes for keeping tires on… One could argue that given a small amount of time it actually starts to dry out and could help keep the tire on…
After talking to many people on both sides of the hookless/Tubeless table and discovery that none of them are using sealant… I would prefer not to use it even more just because that means we are on the same planning field…
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Don’t disagree with anything there. Reailty is I don’t have a compressor and whilst one of my GP5000s seated no issue at all the other was a real pain (CLXII wheels). And you are right, the very worst was my MTB tyres in 2012 with just a track pump.
And 100% I agree with the sealant possibly keeping them on. But it’s that ‘possible’ and the unknown time between possible makes it worse to start, makes it better later that adds more confusion to what is already a hot mess of confusion, as evidenced by this thread, the 3 rounds of Josh youtube videos.
Again, for clarity, not a critique of what you are doing, just flagging a ‘gap’ that’s not being covered yet.
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Yea I hear ya. I was surprised at first when I was learning as well. but the more I asked around the same answer kept coming back and so… I was like… Well if everyone even on other sides of the table are doing it all the same. must have some merit to it 
@marcag since https://www.bicyclerollingresistance.com seems to be a lot of peoples stone tablet…
Why is everyone still talking about the Conti 5000 TT when the top three are
| Vittoria | Corsa Pro Speed TLR 28 | 5.6 W |
|---|---|---|
| Veloflex | Record TLR 25 | 6.3 W |
| Continental | Archetype 30 | 6.8 W |
Can you test with riders who weight 210LBs please…
I mean… Im not a tire manufacture…
You tend to step of the gas when you here the Tu-Tu-Tu-Tu of a delaminating Corsa Pro Speed mid race.
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The rolling road is highly flawed. When you look at their video of it is action, when they roll from one plank to another you can see the plank deflect downwards significantly indicating allot of extra compliance/hysteresis loss that doesn’t exist in real life.
Additionally their white paper assumes non-paved roads.
Corsa pro speed is very fragile so not a great triathlon option
Archetype is a very wide tire. Combo of aero and RR tbd. I get a pair on the 14th
Never touched a veloflex
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I personally prefer aerocoach data over brr.
The Conti 5000 TT is one of the most popular tires amongst pros and front pack age groupers. It’s not the fastest crr wise but has shown better aero properties than other tires like the corsa speed pro according to @marcag and @Xavier (they have made some posts in other threads). It’s a tire that has a good balance between crr, aero, and puncture resistance where you aren’t giving up really anything to be fast.
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