Not only will a torn sidewall quickly put an end to the day's riding, it will will also cost you money. This can be especially painful when the damaged tire still has quite a bit of life left in it, or even worse, is practically brand new. While some cuts will be fatal depending on their size and location, there still may be hope for that freshly gashed tire of yours.
What you'll need:
• High strength glue that works with rubber • Fine grit sandpaper • Cable cutters or scissors • An old tire that you don't mind cutting up
• Using the correct glue for the job is the single most important point. Be sure that your glue is designed to work with rubber - many are not. Follow the instructions carefully and allow the glue to dry for the specified time. • Take a minute after sanding the inner wall of the tire and the patch to clean away any rubber dust that may have accumulated. • Large cuts and tears in the sidewall will not be repairable due to too many of the casing's threads being cut. No matter how big you make the patch you'll likely find that a large bulge will appear in the damaged area once the tire has been pumped up to operating pressure. This is not safe - do not ride it! • I say it in the video and I'll say it again here: Do not try to use a tube patch or any other stretchy material to repair the hole. It will simply stretch, come out of the hole, and you'll end up with yet another flat. You're using tire casing because it is far less elastic.