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oldfatslow
04-06-2020, 06:26 PM
So I have a wheelset I've been running tubeless for a year plus with no issues. I noticed that the rear was losing pressure very slowly between rides and figured it probably needed some fresh sealant. I removed the valve stem without breaking the rim seating, injected about 2.5 ounces of sealant (Stans), replaced the valve core and then inflated the tire with my floor pump to pressure. The tire seemed fine.

I then headed out and did a 50 mile ride. I was approaching the house and was a little short of 50 so I was adding two miles riding slowly through the neighborhood when the rear tire exploded and completely left the rim. Thankfully I was slow pedaling and was able to stop without issue.

The pressure in the tire was what I had been using previously without issue.

I'm thankful for it happening when it did (near my house and while I was going 10mph strolling through the neighborhood). As I've ridden this set up for months with zero issue I do not think it was a rim or tire problem -- it had to be an I'm an idiot problem where I did something to it in filling the sealant or didn't allow it to dry.

What did I do wrong? Should I have left the tire to set like you did with a tubular?

AngryScientist
04-06-2020, 06:33 PM
So I have a wheelset I've been running tubeless for a year plus with no issues. I noticed that the rear was losing pressure very slowly between rides and figured it probably needed some fresh sealant. I removed the valve stem without breaking the rim seating, injected about 2.5 ounces of sealant (Stans), replaced the valve core and then inflated the tire with my floor pump to pressure. The tire seemed fine.

I then headed out and did a 50 mile ride. I was approaching the house and was a little short of 50 so I was adding two miles riding slowly through the neighborhood when the rear tire exploded and completely left the rim. Thankfully I was slow pedaling and was able to stop without issue.

The pressure in the tire was what I had been using previously without issue.

I'm thankful for it happening when it did (near my house and while I was going 10mph strolling through the neighborhood). As I've ridden this set up for months with zero issue I do not think it was a rim or tire problem -- it had to be an I'm an idiot problem where I did something to it in filling the sealant or didn't allow it to dry.

What did I do wrong? Should I have left the tire to set like you did with a tubular?

What you did was SOP for adding sealant, so no, you dont need to let a tire sit after adding sealant.

question: did you check the tire carefully after adding sealant and inflating to ensure the bead was seated evenly all the way around? the easy way to check this is to spin the wheel in your hand and observe the tire, if it has a notable "hop" either up/down or left/right, a portion of the bead is not fully seated.

perhaps the slow leak was the result of a bead that came unseated somehow and the sealant was not the issue.

either way, good to hear you didnt wreck.

makoti
04-06-2020, 07:20 PM
I treat each refill like a new setup & give it 24 hours to set. Would this have prevented what happened? Don't know, but couldn't hurt.
When you let the air out, I'm sure the tire came away from the rim in places. Every time I have let the air out, it did.

R3awak3n
04-06-2020, 07:25 PM
this is very strange. what size tire and what pressure?

oldfatslow
04-06-2020, 07:39 PM
this is very strange. what size tire and what pressure?

700x38c tire. 50lbs of pressure. Tire tubeless max is 60lbs.

Not a hot day here in Austin at all -- highs in 70's at best -- this was at the end of a 3-3.5 hour ride.

R3awak3n
04-06-2020, 07:41 PM
its very strange man but Angry might be up to something. When you put sealant maybe the bead came out and when you pumped it back up it never sat correctly. Scary for sure.

oldfatslow
04-06-2020, 07:43 PM
What you did was SOP for adding sealant, so no, you dont need to let a tire sit after adding sealant.

question: did you check the tire carefully after adding sealant and inflating to ensure the bead was seated evenly all the way around? the easy way to check this is to spin the wheel in your hand and observe the tire, if it has a notable "hop" either up/down or left/right, a portion of the bead is not fully seated.

perhaps the slow leak was the result of a bead that came unseated somehow and the sealant was not the issue.

either way, good to hear you didn't wreck.

LOL. I'm sure I didn't check the tire sufficiently :) to make sure it was seated properly cause Bam! it blew off with what sounded like a gunshot (people is my peaceful neighborhood came out to see the commotion.

I'll definitely be more careful next time.

Is there any way to seat the tire without a full-blown air compressor or one of those super fancy pumps (since we are in a time of social distancing and such I don't want to trouble my shop unless I absolutely have to go in).