A couple of weeks ago on a nice mailing list run by the highly opinionated and often but probably not always right
Peter Jon White (aka PJW), he wrote something I thought was dumb. In a thread started by the innocent question can you use 700x25mm tubes in a 700x 35mm tire, Peter said that:
It's a very bad idea to use inner tubes designed
for skinny tires in fat tires. and for people who have used this combo successfully in the past
You've been a bit lucky. His point was that if you use some smaller tubes than the tire you are using, the tube will stretch and cause strain at the valve stem and tearing in that spot.
I replied that this is BS for a variety of reasons. Bottom line is that if you are tearing out valve stems regularly, you either got a bad batch of tubes or you need to learn how to use your pump without pulling the valve stem out. Mostly the latter. I and many others have done this with no issues at all for years. If you want to read the thread it is
here.
The thread is a microcosm of why I try not to participate in email lists anymore. I am impatient with others on the internet now and again, especially so when people have a knee jerk anti racer/carbon backlash. Also when they are wrong and I am right. I totally hate that. Bikes is bikes, i says, but everyone needs to ride a bit more, especially me. I probably was grumpier than I should have been and should have just let it lie.
But that is not what I am here to talk about. What I am here to talk about is PJW's disturbingly long reach.
Last Friday I was cruising through the canyon on the Big Dummy on the way to the grocery store, I hit a rocky whoopdedo going a bit too fast and I pinch flatted on the front tire.
No big deal, I quickly take off the tire and pull the tube out. It had two big snakebites on it, so no quick patch. I rummage around in the Big Freeloader bags for a spare tube and found I only had a 26x1.0 tube in the bag, but, gasp! I was running 26x2" tires. I immediately thought back to the email exchange and smirked. As I have done for thousands of miles before, I put the skinny tube in the fat tire, pumped it up and rode on to the market.
Later at twilight I was toodling around in the canyons on the way to my next stop when I ended up on a old trail behind the highschool that ended in a new fence. Rather than ride back from whence I came, I cut along the fence through some invisible scrub back to a trail that actually went somewhere. I rode on to the pharmacy and as I pulled up I could feel the front tire going flat. Crap I said. I rushed in to the pharmacy before they closed and when I came out the tire was completely flat. I pulled the tire off and looked and saw not one, not two, but threehundredandfiftymillion goatheads in it. Shit.
I pulled out the easy to find goatheads and then started fishing out the the broken off hidden ones. It took about 30 minutes and the borrowing of a pocketknife from a stranger to get them all out of the tire. Fortunately I had another spare (correctly sized) tube tucked in a hidden spot in the bag and I finished up the flat repair. Curious I thought, usually there are no goatheads in Los Alamos, only once in the last 5 years had I seen a goathead in town.
I briefly checked the rear tire, which was still holding air and appeared not to have any goatheads in it and had a slimed tube in it and rode on home. The next day I hopped on the BD and rode on downtown for some more errands and as I pulled into the post office, my rear tire was going flat. I hopped off the bike and took a quick look at the rear tire and saw not one, but two huge intact goatheads in the SIDEWALL of the tire.
Sidewall? How in the hell did they get there? I pulled them out and pumped up the rear on the big dummy, hoping the slime would hold. The rear tire on the big dummy is pretty hard to get to due to the rack and bags (
previously) which is why I put a slimed tube in there. But even pumping it up is a pain with a small pump, I was kind of half lying on the ground as I pumped it up, but I got it full up. With that done I dipped into the coffee shop for a bit, got some bags of grounds for compost and, as I came out, I saw the rear tire is flat again.
Crap. I pump it up again and spin it real good to get the slime to spread and wait a bit, it is still holding, so off I ride. About a mile down the road, I feel the tire going flat. Crap crap crap. I guess there is no getting around it, I unload the bags on the back, pull off the rear tire and look for thorns. There are none. I pull out the tube, and pump it up and there is no leakage. I pump it up more and see one tiny hole that is more or less sealed by the slime. I pump it up a bit more and see that it is less sealed by the slime and the tube deflates. There is very little that is more depressing than a slimed tube that does not seal. Then you have a heavy messy flat tube that is hard or impossible to patch. Crap.
I check the tire for remnant thorns. There are none. I flip it inside out so I can really feel the inner surface... Nope, no thorns. I flip the tire back right side out and the bead is rolled up on itself. Huh?
I invert it again and flip it back the otherway. Now the other bead is rolled up on itself. crap crap crap. I have changed hundreds, maybe nearing thousands of flats in my life and I have never had this happen before. After about 15 minutes of this I bust out the tire irons and force the bead to unroll, cutting my hands in the process. I replace the tube with a fresh (correctly sized) one and pump it up and spend a few minutes getting the wheel back on the bike and the bags repacked and off I go home. And on the way home, the rear disc brake stops working and the front one starts squealing uncontrollably when applied.
I think I spent about 2 hours over two days fixing flats that should not have happened in Los Alamos. I also now have two disc brake problems that I did not have before. I blame this on angering the more-powerful-than-I-thought Peter Jon White.
I conclusion, even if you disagree with PJW and you know he is wrong, do not do so in public internet forums. He will visit upon you a whole mess of goatheads and unusual tire misfortunes plus odd braking issues. I am sorry PJW, I am sorry I was uncivil on your email list and I am very sorry that I said that you can use small tubes in big tires with no ill effects. Clearly if you do, bad bad bad things will happen. Please, no more goatheads. I am sorry.
Maybe I need to order some LED generator lights to appease him.