Repair cut in sidewall of tubeless tyre On my latest ride I managed to put a cut in the sidewall of my front tyre (Specialized S-Works Purgatory 26x2.2"). The sealant (Stan's No Tubes) didn't manage to seal the cut, presumably because the sealant lines the tread and not the sidewall.

While I was out on the trail I re-inflated the tyre and lay the bike on its side to seal the cut. Everything seemed fine until I got on the bike to ride it again, as the tyre rolled it deformed slightly and opened up the cut again. I managed to get home but had to re-inflate the tyre a couple of times to get there.

This post suggests the use of a Tire Boot but on the Park Tool site it suggests that it is only good for tubed tyres: "...in any tubed tire...".

As you can see, the cut seems fairly minor but the sidewall is quite thin, is there any chance of repair or is it time to invest in some new rubber?
The solution to fix this was in the Pinkbike article suggested by @Batman in the comments to the question.

If you buy a radial tyre patch designed for a car then chances are it'll be plenty big enough to patch a hole in a bike tyre. I just went for some cheap ones on eBay. Add the vulcanising glue (plenty of it) to the inside of the tyre and stick the patch on. To be extra safe I added some glue around the edges of the patch after it was in place too.

As you can see in the photos below, there is almost no noticeable bulge on the tyre.

I've ridden the bike a couple of times since reinstalling the tyre and it has been flawless, no problems with the tyre and you certainly can't feel the patch when you're riding.




I realise there is no single solution that will work for everyone who finds themselves with a cut on the sidewall of their tubeless tyre but this solution worked very well for me.