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Alloy Bike Seatpost Reducer Shim, 100mm Length Aluminum Bicycle Reducing Sleeve Seat Post Tube Adapter for MTB,Mountain,City Bike,Road Bike
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Alloy Bike Seatpost Reducer Shim, 100mm Length Aluminum Bicycle Reducing Sleeve Seat Post Tube Adapter for MTB,Mountain,City Bike,Road Bike
Home E-Bike Parts Seat Posts Alloy Bike Seatpost Reducer Shim, 100mm Length Aluminum Bicycle Reducing Sleeve Seat Post Tube Adapter for MTB,Mountain,City Bike,Road Bike
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Alloy Bike Seatpost Reducer Shim, 100mm Length Aluminum Bicycle Reducing Sleeve Seat Post Tube Adapter for MTB,Mountain,City Bike,Road Bike

$9.99

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Category: Seat Posts Tags: 100mm, Adapter, Alloy, Aluminum, Bicycle, Bike, BikeRoad, E-Bike Seat Posts, Length, MTBMountainCity, Post, Reducer, Reducing, Seat, Seatpost, Shim, Sleeve, Tube
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Description

Price: $9.99
(as of Mar 16, 2025 23:28:56 UTC – Details)


Product Description

cogster seat tube reducer adapter 31.6mm to 34.9mmcogster seat tube reducer adapter 31.6mm to 34.9mm

Cogster, COGSTER, cogsterCogster, COGSTER, cogster

Whether you’re a beginning rider or a passionate cyclist, you can count on us to provide great products, every step of the way.

At Cogster, you won’t only find what you need; you’ll get the outstanding quality!

COGSTER Seat Tube Reducing Sleeve

A revolutionary solution to common bike fitting issues

This indispensable accessory is specifically designed to fit seamlessly between your bike’s seat post and seat tube, effortlessly adapting smaller seat posts to larger frames.

The Reducing Sleeve is ideal for an array of bicycles including MTBs, mountain bikes, city bikes, and road bikes, ensuring an accurate fit regardless of the bike model.

Comes in various sizes to accommodate different bicycle seat post diameters and seat tube diameters. Made of 6061 high tensile aerospace alloy with Full CNC finish. They are made to 100mm length.

cogster seat tube reducer adapter 27.2mm to 30.9mmcogster seat tube reducer adapter 27.2mm to 30.9mm

Effortless Installation

Designed for tool-free setup, ensuring a hassle-free process that gets you back on your bike with ease.

Installation

.

Step 1 – Measurement

Check the seat post outer diameter and measure the seat tube inner diameter to determine the reducing sleeve size.

Step 2 – Insert the sleeve

Insert the smaller end of the seat post reducing sleeve into the seat tube.

Note: The sleeve’s wider end must be facing upwards, and its notch should align precisely with the notch on the seat tube.

Step 3 – Push the sleeve

Push the seat tube reducing sleeve down firmly until it reaches the larger end.

Step 4 – Install the seatpost

Slide the seat post into the sleeve, aligning it correctly. Adjust the height to your preference and secure it according to your bike’s seat post clamp or collar instructions.

Step 1.

Step 2.

Step 3.

Step 4.

cogster seat tube reducer adapter 25.4mm 27.2mm to 30.9mm 31.6mm 33.9mm 34.9mmcogster seat tube reducer adapter 25.4mm 27.2mm to 30.9mm 31.6mm 33.9mm 34.9mm

Easy Integration

Our reducer adapters offer the perfect answer for riders looking to adapt smaller diameter seat posts to larger seat tubes. Plus, we’ve got you covered with sizes tailored specifically for 34.9mm seat tubes – the gold standard in modern bicycle frames.

Cogster Bike Seatpost Adapter Shim serves as a crucial part that adapts smaller seatposts to larger tubes, ensuring a proper fit.
Comes in various sizes to accommodate different bicycle seatpost diameters and seat tube diameters.
CNC’d from 6061 aerospace alloy, this bike seatpost shim balances superior strength, light weight, and corrosion resistance for long-term use.
Featuring tool-free installation, this bicycle seat post tube adapter is designed to avoid damage to the bike frame or seatpost, ensuring ease and safety.
By enabling the use of a different size seatpost, you can adjust the height or tilt of your saddle more accurately, thus improving your overall cycling comfort and performance.

Customers say

Customers find the bicycle seatpost functional, fitting well, and providing good value for money. They say it works well without issues, fits perfectly, and is of good quality. However, some customers feel the plastic material doesn’t look or feel like alloy.

AI-generated from the text of customer reviews

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