AR-PRO (2-Pack) 4.10/4.50-18" Heavy duty Dirt Bike Inner

These AR-PRO 4.10/4.50-18 inner tubes (2-pack) are heavy-duty butyl replacements with TR4 straight valves designed to fit a wide range of 18" dirt bike rear tires.

Swapping a worn or punctured inner tube is one of the quickest ways to get a dirt bike back on the trail. The AR-PRO 4.10/4.50-18 tubes come as a pair and are built from thick butyl rubber to resist punctures and absorb trail shocks. They match common 18" tire sizing—4.10 and 4.50 widths and related numerical designations—making them suitable for many motocross, enduro, and trail motorcycles.

What sizes and valve type does this tube fit?

The tubes are sized for 4.10/4.50-18 tires and also correspond to common numeric listings like 110/100-18, 110/90-18, 110/80-18, 100/100-18, 120/90-18, and 120/80-18. Each tube uses a TR4 straight valve stem compatible with standard valve caps and pumps.

• Designed for 18-inch rims and 4.10–4.50 tire widths
• Works with 110/100-18 through 120/90-18 size notations
• Includes TR4 straight valve stem for easy inflation
• Valve fits common pumps and air gauges

How durable and puncture-resistant are these inner tubes?

AR-PRO tubes are made from thicker butyl rubber than standard consumer tubes, improving resistance to typical trail punctures and pinch flats. They’re not invulnerable, but the heavier material offers better shock absorption and longer service life under rough riding conditions.

• Thick butyl construction for enhanced durability
• Improved shock absorption to reduce vibration
• Increased puncture resistance compared with thin tubes
• Self-sealing properties reduce immediate air loss from small punctures

Which bikes and riding styles are compatible with these tubes?

The 4.10/4.50-18 tubes fit many compact to middleweight dirt bikes used for trail riding, motocross, and enduro. They are appropriate for rear tires on models from major manufacturers as well as popular Chinese and pit-bike brands when the tire size matches.

• Fits Yamaha TTR230/TTR250 and similar models
• Compatible with Honda CRF230/CRF250 and comparable bikes
• Works on Suzuki DRZ250/DR200/RM250 and Kawasaki KDX/KLX variants
• Also suits TaoTao, Coolster and many pit-bike allocations

What should I know when installing or handling these inner tubes?

Handle the tubes carefully to avoid pinches and tears during installation. Inflate slightly before seating to remove twists, ensure the tire bead sits evenly, and avoid using sharp tools that could damage the rubber or valve stem.

• Partially inflate before inserting to prevent twisting
• Check bead seating on both sides of the rim evenly
• Do not use sharp tools near the tube during installation
• Replace worn valve cores or use new caps for secure sealing

Who is this for: Riders who need a reliable, budget-friendly spare or replacement set of rear inner tubes for 18" dirt bike wheels. These AR-PRO tubes are suitable for weekend trail riders, pit bike owners, hobby MX riders, and anyone who wants a thicker butyl option for improved durability and ride comfort. They offer a practical balance of compatibility, toughness, and straightforward installation for common 18" rear tire applications.