The Massi 24-inch 24x1.75/2.125 inner tube, item number 49661, is designed for bicycles fitted with 24-inch tyres between 1.75 and 2.125 inches wide. It features a 33 mm Presta valve and is made from butyl rubber, a material commonly used for its excellent airtightness and air retention properties.

With its versatile size, this inner tube is particularly suitable for 24-inch mountain bikes, junior bikes, children’s bikes and all-round bikes fitted with a Presta valve. It weighs approximately 160 g.

Massi, 24-inch inner tube

A suitable inner tube is essential to ensure a bicycle tyre functions correctly. The Massi 49661 covers a range of sizes from 24x1.75 to 24x2.125, making it suitable for use with various tyre widths on 24-inch rims.

This versatility makes it a practical solution for replacing a punctured, porous or damaged inner tube without having to change the tyre.

Massi e 49661 is also listed as MS-49661 by some retailers.

Compatible with 24x1.75 to 2.125 tyres

The inner tube is suitable for tyres with the following dimensions:

• 24x1.75
• 24x1.90
• 24x2.00
• 24x2.125

The exact range specified is 24x1.75-2.125. This corresponds in particular to 24-inch tyres designed for mountain bikes and junior bikes.

To check compatibility, simply compare the dimensions marked on the tyre sidewall with those indicated on the inner tube.

33 mm Presta valve

Massi e 49661 is fitted with a 33 mm Presta valve.

The Presta valve, also known as a French valve or fine-threaded valve, is particularly common on sports bikes and certain small-diameter wheels fitted with rims with the appropriate valve hole.

A length of 33 mm is generally sufficient for a standard 24-inch rim, whilst remaining compact.

Please note: this inner tube is not suitable for rims requiring a Schrader valve. It is therefore important to check the type of valve currently fitted to your bike before ordering.

Made from butyl rubber

Massi ’s inner tube is made from butyl. This material is widely used in bicycle inner tubes due to its ability to retain air and its good durability in everyday use.

In particular, butyl offers:

• good airtightness;
• good pressure retention;
• cost-effective production;
• standard fitting with tube-type tyres.

The inner tube is therefore a simple and affordable solution for maintaining a 24-inch bike.

For 24-inch mountain bikes and junior bikes

The 24-inch size is very common on bikes designed for children and young cyclists, but also on some small mountain bikes.

The 24x1.75/2.125 Massi e can therefore be used for:

• 24-inch junior mountain bikes;
• 24-inch children’s bikes;
• 24-inch city bikes;
• all-rounder bikes;
• certain small touring bikes.

It is only suitable for wheels where the tyre diameter and width match the specified dimensions.

Technical specifications

• Brand: Massi
• Productcode: 49661
• Product reference: MS-49661
• Type: bicycle inner tube
• Diameter: 24 inches
• Dimensions: 24x1.75-2.125
• Compatible width: 1.75 to 2.125 inches
• Valve: Presta
• Valve length: 33 mm
• Material: butyl rubber
• Weight: approx. 160 g
• Use: mountain bikes, junior bikes, children’s bikes, all-round bikes
• Tyre type: inner-tube tyre
• EAN: 8430495119352

How to choose a 24-inch inner tube?

Choosing an inner tube isn’t just about the wheel diameter. You need to check three main factors:

1. The diameter: in this case, 24 inches.
2. Tyre width: between 1.75 and 2.125 inches for this model.
3. Valve type: Presta 33 mm.

These three specifications must match your wheel and tyre.

For example, if your tyre is marked 24x2.00, the 24x1.75/2.125 Massi s. However, if your tyre is marked 24x2.40, this inner tube is not designed for that width.

Fitting the inner tube Massi

Replacing an inner tube is a relatively simple process, but taking a few precautions can help prevent another puncture.

After removing the wheel and demounting one side of the tyre, remove the old inner tube. Then carefully inspect the entire inner surface of the tyre for any thorns, pieces of glass or other foreign objects.

Also check the condition of the rim flange.

Next, gently insert the new inner tube, then position the Presta valve in the rim hole. Gradually slide the inner tube into the tyre and re-fit the final sidewall, taking care not to use excessive force.

Inflate the inner tube slightly before inflating the tyre to the pressure recommended by the tyre manufacturer.

Maintenance and puncture prevention

A well-maintained inner tube is better able to maintain a consistent pressure.

It is advisable to:

• check the pressure regularly;
• avoid riding with a tyre that is significantly under-inflated;
• check the condition of the tyre after a puncture;
• replace any inner tube showing significant wear and tear;
• check the rim flange regularly;
• carry a spare inner tube when out cycling.

For bikes used by children or young cyclists, regular tyre pressure checks are particularly important to ensure the bike remains stable and comfortable to ride.