Got back from a bike ride and noticed a small tear on the sidewall of my tire. I'm wondering if I can just seal it with some Goo Gone or do I need to replace the tire. I do have spares lying around so not a big deal. But I don't want to replace it if I have to. Thanks!
I folded a dollar-bill and placed it between the tube and tire on my last set of tires. That lasted about four months before the tube finally pushed it's way out the tear and popped. Safest bet is to replace the tire. But in a pinch, the dollar-bill trick will at least get you home/to the bike shop.
Unlike on a car tire, the sidewall isn't more important than the rest of the tire, really [ on a car tire, if the sidewall goes, you're going to blow out].
This link from Sheldon is good reading: "If you are mainly concerned with safety/function, there are only two reasons for replacing old tires:
1) When the tread is worn so thin that you start getting a lot of flats from small pieces of glass and the like, or the fabric shows through the rubber. 2) When the tire's fabric has been damaged, so that the tire has a lumpy, irregular appearance somewhere, or the tube bulges through the tire."
I'd probably use some adhesive on it to seal it up unless going on long rides often.
People patch tubless mountain bike tires all the time. You could use a slime tire patch kit, used frequently for Motorcycle, ATV, and Dirt Bike tires as those patches are a bit more durable than standard bike tube patches. It seems like all the amazon review are from mountain bikers. I've used a regular bike tube patch on the inside of the tire as well. It's best to use the larger patches to cover as much area as possible.
With a tear that small, I wouldn't be too concerned running it as long as it doesn't get any bigger. I've been running a couple sets of tires patched like this with no ill effects.
Alternatively, I've also run a tire with a park tool tire boot for months without any issue.