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Discussion Starter · #1 ·
Well, just a few days ago I prepped my Alexrims xd Lite & put a brand new specialized purgatory control tire on it (front only, I was trying one at a time). I used the 2oz of Stan's and lots of soapy water to help the bead seat.

I rode it around the street a little bit, and it held air pretty well.

Today, maybe 3 days later, i went riding and rode off of a ~3-4 foot culvert pipe (square) into a grassy area.

I landed both wheels at the same time, but immediately heard a loud farting noise and went over the handlebars. I bounced a little on the top of my head (thank you, helmet) and rolled out of it. The bike flew off my feet and went a few yards further.

The front tire was completely off the bead, and the front wheel is kinda bent and wobbly now...

I was able to get the bead seated again, using the little CO2 inflator, and rode back home.

My first experience with tubeless is not all that fantastic; although it was probably my fault for using a rim not specifically designed for tubeless use. I think I'll be going back to using tubes.

Now I need to figure out how to get my rim straightened again. I guess there's a little wrench I can buy.
 

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Sounds like the combination of too low of tire pressure, rimstrike, and non tubeless ready wheelset. You can try adding more PSI to your tires to help it from rim-striking/burping. If your budget allows get a tubeless ready wheelset such as Stans notubes Crest or Flow.

What PSI did you have upfront by the way, also what is your wieght?
 

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I don't know if that was a tubeless issue.

If you hit as hard as it sounds like you did, you likely would have pinched a tube.

My brother just crashed hard last weekend, and blew the tire off the bead of his rim as well. Easton Haven 26", which I understand are tubeless ready rims.
He hit so hard that the front end twisted, and again, the tire blew off.

This sounds like a simple crash, not a failure of the tubeless setup. I'm thinking something on the impact itself took the tire off the rim, which again, if it would have been tubed, probably would have resulted in a pinched tube and possibly also a blown off the rim tire.
 

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R.I.P. DogFriend
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I weigh about 100 lbs more than you do and have used up three 29" Purgatory front tires, all tubeless. I've never run more than 30 psi and have yet to burp one. Something doesn't quite add up unless that Alex rim is unsuitable tubeless use. It's kind of the wild, wild west out there for doing ghetto-tubeless conversions, but I have had very good luck with Specialized 2-Bliss tires.

An 18mm inner width rim is getting toward the narrow end of the rim width range, and would be more apt to let the tire 'roll' if subjected to side load, but I still have a hard time imagining that happening if the tire was truly at 30 psi. My best guess would be that the tire had lost some air before actually burping. If it actually did have 30 psi, you might need another layer or more of tape on the bead shelf.

Of course, it would be more confidence inspiring to have a known good tubeless compatible rim to couple with a known good tubeless tire like the Purgatory. My suggestion would be to use either a rim from Stans (Arch EX or Flow EX) or a WTB Frequency (i23 or i25). there are more that work well enough, but the ones I mentioned are generally no-brainers to set up tubeless.

Since the rims you have are somewhat of an unknown quantity regarding tubeless use, it might be a good idea to go back to tubes until you either get more data and information for using the Alex rims tubeless, or get some rims designed for tubeless use.

FWIW, I have been cleaned off of my bike by a rock hiding in the grass myself. I never saw it coming and was all of a sudden sent flying through the air superman style. It happens. Be safe out there.
 

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Well, just a few days ago I prepped my Alexrims xd Lite & put a brand new specialized purgatory control tire on it (front only, I was trying one at a time). I used the 2oz of Stan's and lots of soapy water to help the bead seat.

I rode it around the street a little bit, and it held air pretty well.

Today, maybe 3 days later, i went riding and rode off of a ~3-4 foot culvert pipe (square) into a grassy area.

I landed both wheels at the same time, but immediately heard a loud farting noise and went over the handlebars. I bounced a little on the top of my head (thank you, helmet) and rolled out of it. The bike flew off my feet and went a few yards further.

The front tire was completely off the bead, and the front wheel is kinda bent and wobbly now...

I was able to get the bead seated again, using the little CO2 inflator, and rode back home.

My first experience with tubeless is not all that fantastic; although it was probably my fault for using a rim not specifically designed for tubeless use. I think I'll be going back to using tubes.

Now I need to figure out how to get my rim straightened again. I guess there's a little wrench I can buy.
Standard tires, Standard rims, no tubes, sealant, does not equal tubeless.
Might work.
Might not.
In your case, not.
 

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Yes, that's fonetic
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I weigh like 165 or so. The air pressure was just over 30psi. I've done the jump many times with a different (tubed) tire without any problems or wheel bending...
You said this was 3 days after you set it up. Did you check the pressure on the day it failed or was the 30lbs the initial pressure?
 

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Rogue Exterminator
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Standard tires, Standard rims, no tubes, sealant, does not equal tubeless.
Might work.
Might not.
In your case, not.
This

It obviously was an issue with your rim/tire combination. They were not able to withstand what you are trying to do with them.

Even if you have had a pinch flat with a tube, it would not have been instant failure causing you to crash and bend a rim.

Either buy a proper tubeless set up or run tubes.
I have tubes in one bike and tubeless in another. I am happy with both set ups.
 

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Discussion Starter · #13 ·
just as a follow up:

I took the stans strip out of the tire and threw it in the trash. I put a tube back in and trued up my wheel as best I could. some spokes really tight now, and some rather loose.

I went back to the spot and rolled off it 15x or so, and no problem whatsoever. was a little nervous the first couple times, I have to admit, and was going quite a bit slower.

My son took a really crappy grainy photo of me doing it. For some reason it looks a lot higher over the handlebars than it actually does from the side, lol.

Bicycle frame Wheel Bicycle wheel Tire Nature
 

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You sure the loud fart was from the bike?:) I usually just blame the dog.

The two times I have burped a tire (both times it was on a full UST setup) it was more of a pop than a fart sound.
 

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On wuss patrol
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just as a follow up:

...some spokes really tight now, and some rather loose.

I went back to the spot and rolled off it 15x or so, and no problem whatsoever. was a little nervous the first couple times, I have to admit, and was going quite a bit slower.

View attachment 880888
Video next, please. From below the drop rather than looking down at it. TIA
 
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