Captain Obvious Here:
I'm gonna have to ask the o-o-o-OBVIOUS question
-are the valves tightly screwed into the valve bodies?
That's a very good thought, but yeah, that's the second thing I checked.
I slept fitfully but tiredly enough that I didn't end up getting up until a couple hours before I had to leave for work today, so I simply pulled both tubes out, and put in a much thinner one I'd patched before and has been sitting since the day I setup the Twinnertube 1.0 system.
I did not put in a second one, as it takes some time to work them both into the tire evenly. I didn't have that kind of time before work, especially if for some reason the first tube I tried didn't work, but thankfully it did. It has held 55PSI form the time I installed it until I just checked a few minutes ago, so a little more than 13 hours now, including my ~5-mile commute today.
I did put a spare tube in the toolbox on the bike, but it is one that had the valve stem leak, and I patched it, but have no idea if it will hold.
I examined the tubes briefly when taking them out, and found a pinky-sized hole in one (the one using the secondary valve hole). That hole is almost lined up 180 from the valve stem, and is on the inside circumference of the tube, so my theory is a "pinch flat" on the primary valve hole with the valve stem of the other tube. I do not think that there is enough room for it to expand into the hole normally, but if the other tube went flat first, it could've allowed the still-full tube to expand very slightly into that hole's edge, and then when I tried to air up the flat one on the primary valve hole, it might've pinched the other one, and then later could've cut thru the tube despite the tape/etc I had around the hole.
What is interesting is that I was able to inflate this tube several times after that point, and it held air for a while, even though I'd've expected the Slime to be unable to reach that part of the tube. But I think because the tubes are side by side, the more-inflated one squishes the less-inflated one so narrow that it lets slime ride up the walls and into leaks even on the inside circumference, allowing it to plug holes up there. I see no way it could've plugged a hole this big if it hadn't been being pinched closed by the valve stem of the other tube, though, so that's another part of why I have the theory above about how it was caused.
I didn't see a hole in the other tube, using the primary valve hole, but I haven't tried to air it up outside of the tire yet. Hopefully I'll have time to investigate the tubes in the next few days.
mdd0127 wrote:I think it would be a good idea to look into some maxxis downhill tubes. I might have given you one at some point.....can't remember. They're extremely thick and even though I ride through fields of goatheads and cacti, I haven't had a flat with one yet. I slime them anyway though. I'll dig through my stuff again to see if I have any more spares.
I don't think I got any tubes from you, but the tire I'm using probably did come from you, as well as the one I'd like to use but has knobbies that make it too wide for my frame.
I don't rmemeber any tubes in any of the tires. (except for the two mongoose basher wheels, but IIRC those were normal tubes, possibly even originals).
The thickness of the tube itself I'm not so worried about, but more the quality of the bond between the brass valve stem core-holder, and the rubber of the valve stem part of the tire. That is where I am getting too many failures, unrelated to the rim's hole (not caused by wearing or cutting, it's just a rupture from within the tube, or in some cases complete separation of rubber from brass!).
Mold-line separation is the other place I have had repeated problems, where the tube casing simply splits right along one of the molding lines, usually on the inner circumference where they tend to be thinner.
I generally don't get "normal" flats, as the tire liners and such tend to keep the gnarly road debris stuff out of the tubes, but I sure do get some doozies from all the abnormal sources.
I was looking around and saw that even Michelin offers some DH tubes; and that DH tubes in general don't seem much more expensive than crappy standard or even walmart tubes would be (8-20 bucks, vs. 4-15 bucks), at least online. Might be different at an LBS, so I will have to call around and see. If DH tubes have better valve stem bonds, and are rated for at least 70-100PSI or more, then I am willing to go out and buy at least one to test with.
Any recommendations for good DH brands regarding valve stems specifically would be helpful. I doubt MadRhino follows this thread, but if he does, I'd like to hear his opinion, too.
I'm making good progress on getting the new solar setup installed on my little rv so I might be able to come down soon. Maybe in a week or two. Everything's taking longer that I expect it too but it's moving along at least. Wilbur chewed that cyst off of the back of his leg so now he's got a big gaping hole in it. I took him to the vet and the vet said the stitches would just rip out and sent him home with antibiotics. Hopefully it heals up soon. I'll email you that asr manual tonight. Been so busy I forgot about it!
Poor Wilbur...Bonnie used to do the same kind of thing when she had owies, as did another dog I had a couple of decades or more ago, who got them alot because he was so alllergic to various things that he chewed holes in himself a lot. I'd usually just smear people-antibiotic cream on the owie, then wrap a bandage around it. Then I'd soak another bandage in water and cayenne pepper, and wrap that around the first one after it dried. He pretty much didn't pick at those.
Another dog I'd had long before that didn't care what I put on them, she'd eat any bandage I put on her.
At one point when she really hurt her leg, I had to make a little metal "cast" for it that I bolted togehter around the leg to keep her from licking it till it wore thru to some major blood vessel.
She was kind of a neurotic dumb dog, that was pretty smart in some ways.
No hurry on anything; life is always a mixed bag of fast and slow and hurry-up-and-wait.
The ASR88 is still sitting on the table awaiting time enough to poke at it's guts again, to see if I can hand-wire across all the corroded traces and thru-holes, once I figure out where they go. Hopefully that will bring it back to life, instead of having to buy a new or repaired board.
Also, I forgot to get your static mat/strap and your Meanwell back to you when you were here last.
Remind me about those when you are here next!