Cycle Tech Review, UK 11.2023

The Effetto Mariposa Tyre Invaders for tubeless systems is designed to protect your rims from hard impacts on the trail. Made from a high density EVA, it’ll absorb the impacts, but not any sealant. It comes in five widths from 32 to 80mm and one length. You can cut it down to fit 26, 27.5 or 29″ tyres. As well as protecting your rims, the Tyre Invader will also help prevent pinch punctures.

So how did I find them? Let’s start at the beginning with installing them. You can easily cut the Tyre Invaders down to whatever size you want; I put them on some 700c wheels for my gravel bike. I followed Effetto’s instructions and pre-stretched them over night. Not sure if this made much of a difference, but it took around five minutes to get one into the tyre. The difficult bit for me – and remember this will be different depending on your wheel/tyre choice – is then fitting the tyre.

Wheel & tyre choice?

I was using Handsling’s own carbon wheels and Vittoria’s 44mm Mezcal tyres for this test. Getting the tyres to fit over the insert was a bit of a faff. It took less than ten minutes, but required some serious self-control not to turn the air blue! As a side note the first tyre I fitted – in the video below – I did before filling with sealant. The second tyre had sealant and I tried fitting it without cleaning it; big mistake! The sealant turned everything into a slippery nightmare. Definitely clean your set-up before installing an insert.

The important bit is to make sure that the liner is sitting on top of your rim, protecting them. So now it was time to try them out. My local trails feature a lot of flint that hides in the grass, the gravel, under cow-pats or embedded in the chalk; it’s everywhere. This was the main reason for fitting the Tyre Invaders, I was having to run my tyres a lot harder than I wanted to, to protect them. On events like the CX Century, which runs across the Downs, rock strikes cause loads of punctures and wreck rims. I have a set of aluminium rims that have taken so many dings, that they’re now unrideable.

Tyre Invaders out on the trail

Once I got them on I found I could run my tyres 5-10 psi lower than normal. This has given me a huge increase in comfort and control. I can now blast through rocky sections almost as fast as on my Mtb, the Tyre Invaders soaking up the damage. While you can feel when you bottom-out, it’s a lot less worrying than without them. You don’t hear/feel that ‘crack’ as you hit a hidden flint, more a soft ‘thump’.

As to whether they slow you down with the extra weight, I can only say that on my little off-road test ramp they don’t seem to have a negative effect. This is a rough tarmac/gravel path that slopes down allowing you to pick up loads of speed. It then rapidly pitches upwards, here slower wheel set-ups require me to start pedalling after about the three-quarter mark. With this set-up I can freewheel the whole way, that’s proof enough for me. On the road they don’t feel noticeably slower, apart from the fact that I’m now on a softer tyre.


I’d definitely recommend the Tyre Invaders if you ride on anything rocky and want to keep your pressure low. I’m seriously thinking about using them for any UCI gravel races I do next year. Losing time from a puncture that I could have avoided thanks to an insert, would be irksome. Especially for an event that I would have invested time and money getting to.