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Flat Tire Defender - FTD II 27.5'' , 29" & Mullet kit


Let’s face it, in today’s world of mountain biking if your not running foam inserts your not winning!


Flat Tire Defender is the original foam insert designed for mountain bike competition.FTD has lead the charge since 2015 winning our first Enduro World Series championship & World Champion Downhill titles and backing those up with 2016 & 2017 World Cup Downhill series championship and USA National championship titles.Get FTD II or get left behind!


With so many foam inserts on the market these days and every brand having a performance story, how do you decide which is right for you.

One of the ways we test Flat Tire Defender is a simple hammer impact test that virtually any consumer can duplicate. Yes, we do perform laboratory test using high tech equipment but we’ve found laboratory test do not always correlate to ‘real world’ conditions.

Also, our rider survey’s have shown they primarily buy foam inserts as a way to protect rims. Yes, this is important but Flat Tire Defender does so much more. In the video you’ll notice when the hammer hits the foam it makes a different sound.


Pay attention to the sound of FTD II.


You’ll notice it’s much quieter. This correlates to how the foam absorbs wheel impact and rebounds quickly for the next impact. And how the FTD II material looks after impact. Enjoy the ride!


It’s Hammer Time!


Features comparing old versus new Flat Tire Defender; FTD II is 40% wider to maximize rim protection and dampen out suspension harshness on rough terrain, 30% taller to maximize tire sidewall support and allow lower tire pressure for increased traction, light weight to minimize rolling resistance and un-sprung weight, excellent high quality foam rubber based material (no pool noodle here).

All this at a very affordable price!

Based on Flat Tire Defender field testing, we’ve found on average, tire pressure can be reduced approximately 10% from a tubeless tire pressure without foam inserts.

PSI Guide*

FTD II (27.5″ & 29″): Range 24psi to 29psi

  • Fits Inner Rim width 28mm to 40mm

  • Kit Contains Foam Insert & Valve Stem

  • Super glue is provided to assist in adhering the two ends together. View Install Guide.

  • Recommended Tire Width 2.30/2.80

  • 27.5″ Weight 200-220 grams (each)

  • 29″ Weight 230-250 grams (each)

Watch Install Video:

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