"Rubber SEE-ment"

Every once in a while, I’ve err’d in my line choice resulting in a good hard rock strike. And every once in a while, POW… I’ve punctured one of my tubeless tires. Some will seal right up by rotating the tire to the lowest point and allowing the remaining tubeless sealant to work it’s magic. But every now and again, the hole is just too big for the sealant to work. If it’s early in the ride I’ll unseat one side of the tire, install a tube, inflate (and many times I can’t get the tire to reseat which is fine) and get back home so I don’t do any damage to the rim so I can patch the tire from the inside using Park’s VP-1 vulcanizing patch kit. If it’s close to the end of the ride/loop, I’ll just walk out to my car if I’ve driven. Which I did last night since it was a short walk to the Pony. So last night when I returned home, I discovered that not just one but ALL THREE of my Park supplied cement tubes had evaporated. Ugh..

So it was upstairs to the studio and jump on the computer to see if there were readily available alternatives. Some research pointed to some using common household rubber cement as a fix. Or dental floss to sew up the slashed sidewall and a piece of spare tube cemented in place. Some were using super glue as an alternative but I didn’t like that as super glue’s tend to dry and be on the hard side. The glue needs to be flexible when dry to retain the tires suppleness and not create a section of tire that won’t move/stretch under load. Plus I didn’t know how that would play with the sealant long term. One thread though suggested using the same stuff automotive shops use to patch tires. Hmm… This seemed like the hot set up. Good enough for car tires, I think it would work well enough for bicycles and tubeless tires. I had PLENTY of patches from Park. Rema was another traditional patch option. So in the morning, off I went to an AutoZone to pick up some automotive rubber cement. What the AutoZone carried was an 8oz fluid can of Rubber Cement by Slime. You may recognize that name. That’s because they are one in the same that makes Slime sealant. Another option is Rema Cold Vulcanizing Fluid.

So back home and do the dirty work:

– Remove Tire
– Clean out all the sealant.
– Clean up the spot of the slash, remove any drive sealant and dry.
– Rough up the section with a bit of supplied emory.
– Apply a thin coating of Slime Rubber Cement. (A quick whiff of this stuff and yup… about the same smell as the Park stuff.)
– Remove the foil backer of the patch, apply firmly and then clamp it with lots of pressure in a vise or clamp with wood block backers.
– Let dry over night.

Then it set everything up as you would normally with a tubeless tire. And heck if this stuff didn’t work really well! The rubber of the tire where the slash happened I’ve left intact. I may trim a bit of the excess “flap” off but I think i’ll leave it there and see how it goes. But it’s holding fast (tire is a WTB Riddler TCS 2.25 – They NEED to make this in a 2.4″ tire…):


So if you run into the same problem I did, head over to your local automotive supplier and ask about their tire patch cement. The fella down in Milford NH’s AutoZone knew just where to take me. Tubeless tires CAN be repaired. IT depends just how large that slash / hole is however within reason. Some slashes are just too big to repair, but it can be done. A small hole can be plugged and there’s plenty of solutions for that kind of repair. But if your glues dried up, look for Slime Rubber Cement. Just don’t huff too strongly – which I didn’t do. Open that jar at arms length and yeah… that stuff’s potent! Good luck and happy repairs.