Tyreinvader by Effetto Mariposa Blocks MTB Tire Snake Bites for a Scant Weight Penalty [Review]

Save your tires from bites and rims from strikes, with one simple piece of sturdy foam. Tyreinvader mountain bike tire inserts are lightweight and affordable.

You may know of Effetto Mariposa for their Caffelatex foaming tire sealant.

Are tire inserts an industry Band-Aid to tide us over while we wait for an integrated tire or rim-based solution? We will have to wait patiently for an answer to that query, but in the meantime, I will be running some foam in my rear tire. My backyard trails are rocky enough to eat through the toughest of tires, reshape alloy rims into obsoletion, and crack carbon like a brittle eggshell. Shorter story: Italy is a fabulous place to test tire inserts.

In 2018, the Swiss bike brand Effetto Mariposa dropped in with one of the lightest and most affordable rim and tire protection strips on the market, aptly named the Tyreinvader. The protective strips are made of high-density EVA, which Effetto Mariposa reports will absorb impacts and not sealant.

Setup notes

Check out the video above for a quick overview of the setup procedure. Overall, the Tyreinvader strips were far easier to mount up than other inserts I have used, but that’s not to say they were as simple as mounting an empty tire.

New inserts sit close to the rim and have to be pushed out of the way to get the tire on. I recommend the following steps:

  1. With your rim taped, and valve inserted, mount one bead of the tire.
  2. Cut the Tyreinvader to the appropriate length for your wheel size, and zip tie the ends together.
  3. Slide the Tyreinvader inside, and fit it over the rim all the way around your wheel before mounting the second bead.
  4. Put your wheel on the ground, cassette side facing down, with something soft between the cassette and the floor to keep from damaging any of the cogs. I typically use an old tire under the cassette, folded up so that it lifts the tire off the ground a bit.
  5. Pull 40-50cm of the bead into the rim channel and then put that portion of the tire between your knees and the ground. This will prevent the tire from slipping off that part of the rim while providing a little padding for your knees as you work.
  6. With your knees holding one side of the tire on, pull the rest of the tire bead onto the rim, making sure to push the bead down into the rim channel as you go to keep the bead as loose and workable as possible.
  7. With the Tyreinvader and your tire mounted, add sealant through the valve, pump until both beads are fully seated, and go enjoy a flat-free shred.

Finally, there is no need for special valves to make the inserts work with your current tubeless system. The Space Invaders laser-cut graphic around the protective strip allows sealant and air to flow freely throughout, like a traditional tubeless system.

I placed the zip ties on the side opposite the valve to provide better overall weight balance around the wheel.

The dual zip tie connection has lasted far longer than those on similar inserts I have ridden with. I have been running a pair of Tyreinvaders in the rear rubber of two different bikes, and I can confirm they work as advertised, and don’t absorb sealant. After a few months of slamming my bike through rocks on a near daily basis, both rear tires are sloshing plenty of latex around, and the inserts are ready to install in some new tires that I will be testing.

Upon removal, the inserts felt as light as the day I received them, apart from being externally coated in sealant. Despite the few cuts they have suffered they don’t appear to be absorbing any fluid. I am confident that the inserts will continue to protect my tires and rims through another set or three of rear treads.

I noticed three longer slices in this Tyreinvader while swapping it from the second to the third tire that it has invaded, though it doesn’t feel like it is absorbing sealant through those rim-incisions.

This must have been a big hit, but my rims still look great and the tire didn’t go flat.

  • €36 (about $50 USD) per pair (available online at Chain Reaction)
  • EVA construction
  • No special valves required thanks to the holes in the inserts
  • Actual weight for Tyreinvader 50 = 65g each
  • 26″, 27.5″, 29″ wheel options
  • Fits cyclocross to plus-size tire widths

Ride feel

I am running one invader in a carbon rim, and another in an alloy hoop. Both of the rims look as good as new after a few months of abuse, indicating that the Tyreinvader has done its job well. I have heard and felt numerous rock strikes, but my rims show no evidence of damage.

For reference, my preferred tire pressure is around 22-24psi in the rear, and 19-20psi front, depending on dirt conditions. I weigh 150lbs (69kg), and both of these inserts were tested on 160mm full suspension bikes. I have raced three enduros with one of these bikes, and experienced zero tire- or rim-related issues.

In terms of handling feel, I don’t have much to report. The inserts are not noticeable in the rear tire. I can see how they might change a front tire’s handling characteristics, but I haven’t needed to run them up front yet. I can ride with the lower pressures I prefer and not worry about punctures or rim-strikes ruining the fun.

Given the invisible nature of the Tyreinvader inserts, I will be riding with them for the foreseeable future. They cut the likelihood of flats and cracks, and give minimal hassle to mount up. If you let someone else mount them you will enjoy all of the protection benefits, and can likely forget about your tires until it’s time for more sealant or new tread.

Thanks to Effetto Mariposa for sending the inserts along for review.