RubeRad

My wife and I swapped her mtb tires front<-->back and in the process switched her from taped-rim tubeless (one rim gorilla tape, one rim kapton) to ghetto flaps (split-tube).

The first tire we did, I made the mistake of trying to get both beads onto the rim in one go, and I think in the process we damaged the split tube. We can pump it to 20-25 ok, but beyond that it suddenly and loudly spews air out the valve stem hole, which I take it to mean that there is damage somewhere in the tube and the air is traveling between the tube and rim to the easiest exit. It's been a few days, we'll check again if the sealant has been had time to dry and if it will hold better now.

The 2nd tire I put on one bead at a time, it took about 5min and was way easier and first go hand-pumped to 40psi. Deflated, took the valve core out, squirted in the sealant, pumped to 55 and it's held all weekend. So that one's ready to drop to riding pressure.

FYI rims are wtb 23(?) and tires are Maxxis Ardent 29x2.4. One tire is TR and one is not. The non-TR is the one that's not working, but as described, the leak is quite obviously not through the tire or bead. Will probably have to buy a new tube to split and chalk the 1st one off as a learning experience.

ronin4740

Went on a Century ride this past weekend. One of the many things I did before starting on the ride was to use the pump to get the tires to riding pressure level. Am 100% certain that the front tire had ~100lbs and the rear had ~110lbs of pressure before I started the ride.

As I was nearing the rest station at around the 54 mile mark the rear end started to feel a little weird when I was turning with the road. I looked down and the tire looked pretty much flat... Got off the bike and was easily able to compress the tire with my hand.

I gingerly rode the bike the remaining couple of tenths of a mile to the rest stop which was fortunately also the lunch stop AND with the bike mechanic setup at his booth. He had a bottle of Stan's which we put into the tire, filled it, spun it and didn't observe any leakage. He pointed out a shallow cut on the surface of the tire but it wasn't leaking air at that point in time...

I finished the ride with a solid tire but some confusion as to how this happened in the first place... Leaky seal at the valve stem which the extra Stan's solved? Puncture which took most of the Stan's in the tire to seal while letting most of the air out??? Still not certain whether I was better off riding a slowly leaking tire for the first 50 miles of the ride or if I'd been better off with a traditional tubed tire which might have gone completely flat or might not have had the initial slow leak...

RubeRad

Probably you were due for a sealant refresh. Sealant dries up over a few months. When it is low, the symptom is slow leakage. I can delay adding sealant for months by just pumping before each ride. A tire may go flat overnight, but if it can last for a 2hr ride, I'll let it ride, so to speak.

ronin4740

Thanks @RubeRad. I suppose this is possible... I did however neglect to mention that these Giant Gavia AC1 tires replaced a set of Giant Gavia racing tires within the past month. Both tires read 90+ PSI and I'd taken a short ride of about 15 miles the day before just to keep my legs loose without issue. I watched the shop mount them so I know he added Stan's to both wheels. Maybe more of it escaped through the valve stem when I've been inflating it than I thought...

In any case I'll keep an eye on the tire pressure over the next few rides, noting what each is prior to riding when I check inflation and go from there.

DrIsotope

During the summer months here in SoCal, I have to check sealant levels every two weeks. Latex isn't magic, and when rolling on asphalt that can easily hit 160º, having it dry up comes as no surprise. Even after years of running tubeless, I still forget at least once a year, and get a "flat," fixed by squirting in new sealant and pumping the tire back up.

Between my two bikes and my wife's bike, in the past two weeks we have combined for 7 punctures where sealant was visible, which would have been flat tires. A wet, mild winter has caused an absolute goathead explosion out there. Median strips are absolutely buried in it.

RubeRad

Well 1mo is very surprising to me for fresh sealant to need replenishing, but DrIsotope has more experience and hot road miles than me. I just take the mtb out a couple hours per weekend, and probably trails are not as hot as asphalt anyways.

squirtdad

curiosity... is the weight of the dried up sealant minimal or do you need to every now and then clean up the old junk? or do you wear the tires down before this happens?

DrIsotope

When the peoples they say, "You have to refresh you sealant more than once a month?!" I simply respond,

DrIsotope

I recently had a 700x35 Hutchinson Overide go 13 months and 5,800 miles, without having anything done to it other than sealant refresh. Never once broke the beads. When I pulled it off the wheel, I weighed it and compared it to the brand new Overide that was replacing it. The old one had gained about 40 grams-- and that was still while wet. The latex solids had probably added around 28g/1oz.

AFAIC, it's certainly not enough weight to worry about.

NoWhammies

In early June I mounted a set of tubeless tyres on mu road bike. I had to replace the rear tyre yesterday (July 22nd) and when I took the tyre off...Nothing! No sealant at all. The tyre was plenty gummy inside, but there was no liquid. I was surprised because we have had a mild summer and none of the crazy temperatures DrIsotope experiences.

I switched to Orange Seal for the first time and I've never experience the 'evaporation' effect with Stan's. Although maybe I've added more Stan's in the past. Who knows?

davei1980

I am running tubular tires on my CX/Gravel/Adventure bike. I got a good deal on the rims and tires (then gave it all back when I had to buy glue)

Wish me luck!

ronin4740

Ugh. I picked up something in the rear tire in the last four or so miles Saturday. The Stan's sealant in the tire did it's job - it sealed the puncture but right in front of it the rubber casing on the tire split, exposing the inner cord material. These tires had easily under 300 miles on them

I'd ordered a set of Continental GP5000 TL tires from Europe (they were a great price) so I'd have a set of non-Giant TL tires on hand in case the Gavia tires died suddenly... While I debated doing the work myself and changing the tires I ultimately decided to let the LBS do it... Glad I did as they needed a bunch of extra Stan's the following day to seal properly. The LBS shop owner says that he see's this a lot - says that often whatever punctures the tire gets stuck between the rubber casing and the cording then gets pushed out another spot in the tire and ruins it...

This really is it on my tubeless experiment though. If I have a puncture ruin the Continentals I'm really going to go back to running tubes in the wheels. If I'd had 40 miles to go instead of 4 on Saturday I wouldn't have made it home...