Serfas 26x4.0–4.9 Fat Bike Inner Tube — 48mm Presta Valve, Replacement Tube

Serfas 26x4.0/4.9 Presta tube (TP264049) is a replacement inner tube with a 48mm Presta valve made to fit 26" fat bike tires from 4.0" to 4.9" wide.

This tube is a straightforward spare or replacement for fat-tire bicycles that use a Presta valve. Constructed for compatibility across the common 26 x 4.0–4.9 size range, the TP264049 provides an affordable option for riders who need to swap a damaged tube or keep a match-ready spare. It works with rim depths that accommodate a 48mm valve stem and is sold under the Serfas brand known for cycling accessories and parts.

How do I know this tube fits my fat bike wheel?

Check three key measurements: wheel diameter (26"), tire width (4.0"–4.9"), and valve stem length (48mm). The TP264049 is sized for standard 26" fat tires within that width range and includes a long Presta valve suitable for medium to deeper rims. If your rim is unusually deep or uses a different valve type, you’ll need a different model.

• Wheel diameter compatibility: 26 inches
• Tire width compatibility: 4.0" to 4.9"
• Valve type and length: Presta valve, 48mm stem

What performance and durability can I expect from this inner tube?

This tube is made as a general‑purpose replacement rather than a high-performance, puncture-resistant specialty tube. It balances affordability and reliable airtightness for routine riding conditions. For heavy off-road use or puncture-prone routes, consider pairing it with tire liners or sealant for added protection.

• Material designed for standard airtight performance
• Good value for regular commuting and recreational riding
• Compatible with sealants if you want extra puncture protection

How do I install and maintain the Serfas TP264049 tube?

Installation follows normal inner-tube replacement steps: partially deflate and remove the tire, seat the new tube inside the tire, and inflate to the tire maker’s recommended pressure. Keep the valve nut snug against the rim, check for pinches, and rotate the wheel after a short test ride to confirm proper seating. Regular inspection for cuts or abrasions helps avoid roadside failures.

• Deflate and remove tire, insert tube carefully to avoid pinching
• Inflate gradually and verify bead seating before full inflation
• Carry a spare or patch kit for long rides

Can I use sealant with this Presta tube and will it affect the valve?

Yes — many riders use liquid sealants with standard butyl tubes to reduce punctures; the TP264049 is compatible with common tire sealants. If you add sealant, follow the sealant maker’s instructions and ensure the Presta valve core is removable if required. After sealing, periodically check valve and rim areas for buildup or leaks.

• Compatible with typical tire sealants for puncture mitigation
• Remove and re-install valve core if sealant instructions require it
• Inspect valve and rim after adding sealant to ensure proper function

Who is this for: The Serfas 26x4.0/4.9 Presta tube (TP264049) is aimed at fat-bike riders who need a dependable, budget-friendly replacement inner tube or a match-sized spare. It suits recreational riders, commuters on wide tires, and anyone who prefers a Presta valve with a 48mm stem for moderately deep rims. If you ride aggressively on rock-strewn trails or require factory puncture protection, you may want to choose reinforced tubes or combine this tube with sealant and tire liners.