36” tube option after Foss disappointment

Hi all, as title suggests I’m considering options to repair or replace a 36” tube after my first puncture today. Pretty unimpressed if I’m honest, started to go soft then went pop and rapidly deflated. When I took off the tyre there were loads of white grains… presumably related rot be system that is supposed to seal the tyre(?)
Anyways I need to get it fixed. Foss tubes seems way overpriced considering this one doesn’t seem to live up to its claims.
What do we reckon to the patches to repair them, these are also expensive but if they work it could be a good option.
How about just putting in a standard rubber tube but then I need to drill the valve hole to make the Schader fit?

Comments appreciated.

How long have you had the Foss tube? Did you install it or someone else?

I guess I consider myself lucky as I’ve used Foss tubes in my 36ers for over 10 years now with no issues. When I get a thorn-type of puncture it slowly deflates and I discover it the next day. I simply press on one of the Foss patches to it, no glue needed.

I’m curious about the “loads of white grains”, hence my first questions. I’ve not seen that in any of my installations or repairs. If someone else installed it I wonder if they added some kind of sealant to the tube.

I installed it myself when I bought it last year. I’ve ridden a fair amount with no issues so far. This appears to be the first puncture.
I thought the debris were sand grains or salt but not idea how they got in there hence I assumed this may be the agent in the tyres that seals it.

The Foss patch will work well to patch the Foss tube. If you want to replace the Foss tube a 29" normal butyl rubber tube is the least expense and fully serviceable.


That is most bizarre. As far as I know, Foss tubes do not have any internal sealant but I could be wrong.

I’ve had two Foss tubes go bad on me. They both developed leaks near the valve stem. There were no sharp objects involved as far as I could tell.

I tried to patch repair them both with the official patches and by heat sealing. Neither technique worked.

After that I gave up and put a 29” tube in my 36er instead. No problems so far.

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Wow ok so a 29er tube works in a 36er? Is it safe?

What typical tube do you use 29x2.3, something like that?

Yes it is safe, many 36" owners use them. A little harder to install and some care must be taken not to pinch the tube. Adding a little air to the tube so it holds it shape will help with installation.

The standard size of 29 x 1.9 - 2.3 works well.

I’m going to have to ask, but did you have them installed the correct way around?

I have to admit I’m like @haskinsc, having never had even a single issue with a Foss tube (but also I’ve never had a puncture one one). I do wonder whether on the side of a road I’d be as careful with the re-installation as seems to be required to keep them operating in tip top condition though…

Yep. I think you asked me this last time I mentioned it :wink:.

One of them was the original tube which came with the unicycle. The other was its replacement. Both installed with the seam on the correct side of the valve hole.

Ah well after waiting two weeks for some foss patches to arrive arrive I duly fitted one (easy job), put it all back together and then within a few minutes I could hear a hiss.
It appeared to coming from the valve area and upon removing the tube again I could see there was now a small hole at the bass of the valve.

I really don’t rate these tubes at all, just seem so delicate and for the cost i think I’d rather put £35 through the shredder than buy another!

I don’t understand the comment about making sure the tube it fitted the right way around. Surely whatever way you fit it (as if it were a directional tyre) makes no difference?

According to Foss, the direction does matter. I really don’t believe it matters that much, but they claim that they are directional: https://static-s3.lecyclo.com/images/info_pdf/foss_instructions.pdf

If you have trouble around the valve stem, it could be your pump. Make sure the pump head attached to the stem is not wiggling as you pump. You can strain the tube that way and it may lead to failures. No idea if this is your issue - just a thought. Also check for burrs or other issues in the rim where the stem is inserted.

I have a Foss tube in a 36 that has given me no trouble at all for a couple of years. I have to pump it up a little more often than a regular tube, but other than that it works great. I immediately bought a spare and patches when I acquired the unicycle, but they’ve never been used. Maybe just luck for me.

Would be interested to know from foss why direction is important. I never even got to ride mine before it punctured.
Everything else seems good otherwise.
Maybe I had a slightly defective tube or just bad luck.

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These are supposedly going to be available as of August 27th. Presta Valve.


They seem to make a big deal about that seam being in front, though I don’t understand why. I just learned about that detail. I have used Foss tubes in my 36 for years, but had two or three flats. One was a “medium” leak, where I rode frantically toward the car until it got too squishy to ride well, pumped frantically with my little pump about 110 times and repeated the process (it was also hot out) until I got there. That one was fixed with a Foss patch. There is no sealant inside the tube, I believe it’s the wall material itself that allows for the self-healing (or heat healing). I have tried the heat healing and it worked for me, but using the patches is way easier and carries less risk.

One of my flats was a hole near the valve stem. My 36" rim has a Shraeder-sized hole, but the Foss tube has a skinny valve, so there’s a lot of play there. I believe this may lead to some of the leaks in that area, if the valve is getting tweaked/bent around, which is hard to avoid when using a pump. Over time it seems reasonable that damage could be caused by such movement. I guess I could make a smaller hole for the valve to fit through, or put some sort of grommet in there to fill the gap?

I like the Foss tubes because they have the coolest-looking valve stems in all of unicycling. :slight_smile: I am not connected in any way to the brand, and still have been unable to find out how/why they ended up with that name, it could be an interesting story!

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