DOMINATE THE TRAIL & RIDE HARDER WITH FLAT TIRE DEFENDER II In modern mountain biking, every second counts — and serious riders know that running a quality MTB tire insert is no longer optional. Introducing the Flat Tire Defender II (FTD II), the original high-performance foam insert engineered to maximize rim protection, increase traction, and elevate your ride on the roughest terrain. Developed for aggressive trail, enduro, and downhill mountain biking, FTD II has been proven on the world stage since 2015. From Enduro World Series championships to World Cup Downhill victories, Flat Tire Defender continues to help riders push limits with confidence and control. Whether you're smashing rock gardens, charging technical descents, or hunting podiums, FTD II gives you the protection and performance advantage you need to ride faster and harder. TECH SPECS Wheel Sizes: 27.5” & 29” Compatible Rim Width: 28mm to 40mm internal width Recommended Tire Width: 2.30” to 2.80” Pressure Range: 24 PSI to 29 PSI 27.5” Weight: 200–220g each 29” Weight: 230–250g each Material: Premium high-rebound foam compound Kit Includes: Foam insert & tubeless valve stem Installation: Super glue included for secure foam bonding KEY FEATURES The Flat Tire Defender II is engineered to improve every aspect of your mountain bike setup: Maximum Rim Protection: FTD II is 40% wider than previous versions, helping absorb harsh impacts and protect expensive MTB rims from dents and damage. Enhanced Sidewall Support: With a 30% taller profile, FTD II stabilizes your tire sidewalls during aggressive cornering and high-speed impacts. Run Lower Tire Pressure: Increase grip, traction, and comfort by safely reducing tire pressure by approximately 10% compared to standard tubeless setups. Improved Ride Feel: The advanced foam compound dampens trail chatter and suspension harshness for a smoother, more controlled ride. Lightweight Performance: Designed to minimize rotational mass and rolling resistance without sacrificing durability. Race-Proven Reliability: Trusted by elite downhill and enduro riders competing at the highest level of mountain biking. PERFORMANCE TESTED IN REAL MTB CONDITIONS Every mountain bike tire insert brand claims superior performance — but FTD II backs it up with real-world testing. One of the simplest demonstrations is our hammer impact test, designed to replicate aggressive trail impacts riders experience on technical terrain. While laboratory testing provides valuable data, we believe true MTB performance must be proven on the trail. During impact testing, FTD II produces a noticeably quieter and more controlled response, showing how effectively the foam absorbs energy and rebounds rapidly for repeated impacts. This translates directly to improved wheel protection, increased stability, and a smoother ride feel on demanding trails. WHY USE A MTB TIRE INSERT? A mountain bike foam insert delivers multiple performance benefits beyond flat protection: Protects Carbon & Alloy Rims: Reduces the risk of expensive rim damage during hard impacts. Improves Cornering Stability: Supports tire sidewalls for more predictable handling in aggressive turns. Boosts Traction: Allows lower tire pressures for enhanced grip on loose, rocky, and wet terrain. Reduces Tire Burping: Helps maintain tire integrity during hard cornering and compressions. Increases Ride Confidence: Ride more aggressively knowing your wheels are protected. BUILT FOR AGGRESSIVE MOUNTAIN BIKING From technical singletrack to full-gas bike park laps, the Flat Tire Defender II is designed for riders who demand maximum performance from their tubeless MTB setup. Whether you ride enduro, downhill, all-mountain, or aggressive trail, FTD II helps you ride faster, corner harder, and push your limits with confidence. RIDE HARDER. RIDE SMARTER. Upgrade your tubeless setup with the Flat Tire Defender II and experience the next level of mountain bike protection, traction, and control. Ride with confidence. Charge every line. Defend every impact. Watch Installation Video: