I was riding home yesterday, and the light was green for me to carry downhill speed through the intersection that always has the worst debris field. As soon as I pass through that junk, I hear a loud TIC-TIC-TIC-TIC-TIC.

Once on the far side of the intersection I pull over, inspect my rear wheel, and find this:



Sorry for the terrible phone pic, but that's a 3cm shard of metal there, threaded into and back out of the side of my Marathon Supreme

Normally with a goathead or such my policy is to leave it in until I get home, because invariably when I pull it out HISSS. But in this case, with the sharp being so big, and hitting the chainstay, I know if I ride on it I will definitely do major damage. So I cross my fingers and pull it out, and -- that's it! No air loss. Somehow (breaker layer?) that thing avoided puncturing my tube. Made it home fine, rode in this morning fine, no loss of tire pressure at all.

Isn't that tire mounted backwards? I mount mine so the point strikes the ground first, to help push the water out sideways. MHO

They are great tires!

Yep, I have found nails, wires, and box staples that way before.

D'OH! I think you're right. I recently took the tires off, squirted sealant into the tubes, and put them back on, I must have put the rear on backwards, I'm pretty sure I would have noticed looking down if the front were like that. I was planning to swap front/rear this week anyways (and take the opportunity to inspect the tube in this trauma area), so I will make sure to put it back the right way!

It's probably a non issue, since it never rains in sunny southern California.

I once picked up a piece of what looked like welding rod in a tubeless automotive tire like that.
It went in the tread near the sidewall, and came out the side of the sidewall, apparently deflecting off the belts.
I pulled out the rod and nothing leaked.

Yes, I don't need the treads pointing in the right direction for rain, I just need it for my own OCD. (now that you pointed it out...)

That's pretty awesome!

My 700x32 Marathon Supremes have a big chunk missing from the tread. I'm not sure what caused it. I heard it happen, but whatever it was didn't stick in the tire. It left a 2mm by 4mm hole that lets me see the breaker layer, but it hasn't caused a flat (though now it probably will on the way home tonight). I've filled it with Shoe Goo a couple of times just to keep rocks from lodging in there, but I'm not sure that really helps much other than making me less anxious.

I did exactly the same thing with my Michelin Protek Cross Max tires. Congratulated myself on doing such a swell job, then realized I'd mounted the front tire backward. And that was *after* using bright red markers to carefully mark arrows on the rims and tires to ensure correct alignment. Beer while doing home mechanics. It's a wonderful thing.

Tires are swapped front/back, and both installed correctly now.

I took a look at the tube and the inside of the tire where the shrapnel went 'through', not a sign of any trauma at all. Just a flesh wound!

I also got my dremel out and filed off my lawer lips, so I'm looking forward to a long and happy future of having a front quick-release that actually releases quickly! I've got about 6 coats of clearcoat on the bare metal so far, it says at least 1min between coats, so I'll put a bunch more on tonight, and let it dry good over night before I actually put the front wheel back on.

Also took my chainrings off so I could install new steel chainring bolts I ordered, but unfortunately I ordered bolts for single cranksets not double. While I had it apart though, I gave the chainrings a good scrub, they were pretty gross. Also 'flossed' my cassette with the hem of an old T-shirt.

A fun night of bike maintenance (no beer though -- that's the biggest mistake I made!)

wow, that's a new one! congrats!

When the bike is upside down, it LOOKS like they are on right. Then you flip it over, and S***! It's cool as long as long as there's enough beer left to redo the job, LOL

Or even not, if you can overcome any OCD tendencies you may have. I usually can't, but intellectually I don't believe that it really matters at all on a tire like that.

My real quandary is cyclocross tires with a chevron pattern. My OCD tells me the tread should be pointing forward on both tires, but the theory (or at least one theory) is that the rear tire should point backward (to grab while pedaling) and the front tire should point forward (to grab while braking). My Michelin Mud2's are even labeled with different arrows for front and rear. With this sort of tire I think it does make some difference, but still probably very minor.

Well even when the bike is upside down, I'm not skilled enough to put tires on while the wheels are still in the frame! I have to hold the wheels up the way they would be on the road (qr left, cassette right) and decide which way to put the tire on.

Yes, I like it when there are arrows to indicate direction, I have seen tires before that were one way for the front, and reverse for the rear, and I've had tires also that were completely different tread patterns front and back. But they were all mtn knobbies.