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Got two flats - bad tires?

593 Views 3 Replies 3 Participants Last post by  highdelll
I purchased a 2008 GF HiFi came with Bontrager Jones AcX Gum-Bi tubeless tires. First flat was a thorn through the side wall and the stans fluid sealed it. Second flat was allen wrench through the tread and side wall and did not seal. Ended up putting a tube in. Both flats were in the first 60 miles of riding new bike. Are these tires not very good that they flat easy or is this to be expected by all tires?
If a new tire would prevent these easy flats and suggestions on a 29 inch tubeless tire?

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Not the tire....

just bad luck. You can run dual ply UST downhill tires and still get puncture flats if the object puncturing the tire is burly enough. Thorns happen! With the thorns we have hear in the midwest (we call em goat heads) they'll penetrate just about any tire. That's where stans comes in, it'll seal em up. But an allen wrench? Now that's a bit unusual. And the fact that it penetrated the tread and the side wall would flat just about any tire with any sealant on the market. And an allen wrench or the like is NOT and "easy" flat. It is uncommon and the tread through to the sidewall configuration makes it very difficult for any sealant to seal. Also a sidewall puncture by a thorn isn't that easy to seal. Stans, as well as other sealants, primarily stay in the tread area of the tire when riding. A little may slosh on the sidewalls from time to time, but not enough to seal a puncture in that area. When you get a side wall puncture, turn the wheel so that the puncture is at the bottom, then lay the bike down on it's side on the side that the puncture is on for a few minutes. This allows the liqud sealant to cover the pucture and do it's thing. Once the puncture seals, air back up and ride. Also if you are getting thorn punctures in sidewalls it indicates that the side wall is running a bit to close to the trail. Up your pressure a little bit to round out the tire more at the bottom when you are sitting on the bike. Unless it's a really big long thorn it shouldn't touch the side wall of the tire to begin with.

Bad tires? Probably not. You've just had a little run of bad luck. On a side note, the Jones ACX 29er isn't the best tire in the world performance wise, but they do pretty well when run tubeless.

Good Dirt
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Squash - thanks for the reply, very informative.
I want to know how you got an allen wrench in the tire :eek:
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