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Mysterious Tubular Leak(3 posts)

Mysterious Tubular Leaktriangleforge
Aug 19, 2002 6:29 AM
Encountered an odd problem with a 'cross tubular last Saturday, and wondered if anyone could offer any insight.

I was riding singletrack out at a local park with a teammate on his mountain bike and kept losing pressure in my rear tire, a Tufo Rhino, treated with the Tufo sealant. I was running the tires fairly low to begin with (around 35 psi to start), but three or four times I had to stop and pump the rear back up as it had gone very soft. (Incidentally, it's downright scary just how much traction you can get in dry conditions with a cross tubular down around 10 psi -- I could always tell it was time to stop and put a little air in the tire when I could: A) feel the tire start to bottom out on big rocks or roots, and B) clean climbs with ease that usually give me fits on my mountain bike!)

The problem is that the tire holds air just fine hanging in the basement or riding on road or smooth trail. My working hypotheses, neither of them very satisfactory, are:

1) there's a problem with the valve, losing air only when the pressure spikes a bit over a big bump,

2) I somehow punctured or snake-bit the tire, which would lose pressure until the Tufo sealant mended the breach. If it had happened once, I'd figure this was it, but three or four times in the course of a three hour ride seems a bit much.

Any ideas?
re: Mysterious Tubular Leakthe mayor
Aug 20, 2002 9:42 AM
Yeah...it has happened to me too. Your sealant has dried out and is leaking only while riding. Put in more sealant and it will be fine for a few more months.
Mister Mayor!triangleforge
Aug 20, 2002 11:53 AM
Thanks for the advice, your honor! I'll give that a try this evening.

Haven't seen you 'round hereabouts lately, or maybe I've just not been paying attention... Or mayhaps you hibernate in the Spring & Summer months ;-)

Cheers!