Foss 36 tube question

[DavidHood]

@scotthue

I had a Foss tube in a drilled rim with the stock green rim tape and multiple tubes failed around there edge of a hole. I think the combination of pressure against the relatively sharp edge of the hole and the thinner tube is what produces the failure. I did use a 29er tube in the same rim, but it also failed in the same manner, however it lasted a while longer than the Foss tubes did (never more than 2 rides). I think that Eric’s idea of using fibre tape could work well but could also add a bit of weight. The expensive solution is to get the Stealth2 rim because it is both stronger and lighter than the Impulse drilled rim, however it does not have the holes, so it works great with the Foss tube.

Also, unlike Bronson’s wheel that John is using, the Foss tube in my rim bulged past the second wall of the rim.

Before UDC added the “Not recommended for rims with cutouts/holes” note on their website, I had purchased a FOSS 36" clear tube with the intention of putting it on my first run (with the drilled Stealth1 rim) Impulse. The original “commuter” (heavy) tube was bulging out of a couple of the holes pretty bad. The tube ended up being a defect (UDC refunded in full, of course) that was fused together in spots so my LBS put the heavier tube back in and replaced the Green Rim Strip tape with duct tape. I’ve put over 1k miles on it since then and it seems to be holding up fine (no bulges). It does not leak air like the FOSS tube in King’s Stealth2 which seems to like to revert back to 40psi whereas the heavy tube in my Impulse is holding tight at right around 60psi. I’m probably taking a hit on rotational weight (the most important kind) with the heavy tube and duct tape on the Impulse. But, if it ain’t broke…

I was thinking about picking up a $6 Green Rim Strip (see picture below) on my next UDC order just to get the color theme back. I guess I will abandon the FOSS tube (based on your recommendation) for that wheel. I’m not going to build up another wheel (funny how the un-drilled Stealth2 rim is lighter than my drilled Stealth1) for my back-up/loaner to be just a “little” lighter.