---
product_id: 620149145
title: "Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike"
brand: "biydoo"
price: "€ 33.44"
currency: EUR
in_stock: true
url: https://www.desertcart.nl/products/620149145-bicycle-rear-derailleur-tourney-rd-ty21-rd-tz31-6-7
store_origin: NL
region: Netherlands
---

# Direct mount & hanger mount options 6/7 speed compatibility Precision forged aluminum alloy Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike

**Brand:** biydoo
**Price:** € 33.44
**Availability:** ✅ In Stock

## Summary

> 🚴‍♂️ Shift into the future with precision and style!

## Quick Answers

- **What is this?** Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike by biydoo
- **How much does it cost?** € 33.44 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.nl](https://www.desertcart.nl/products/620149145-bicycle-rear-derailleur-tourney-rd-ty21-rd-tz31-6-7)

## Best For

- biydoo enthusiasts

## Why This Product

- Trusted biydoo brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Seamless 6/7 Speed Shifting:** Optimized for smooth, reliable gear changes on diverse terrains.
- • **Durable Aluminum Alloy Build:** Forged for precision and longevity, ensuring stable performance ride after ride.
- • **Direct & Hanger Mount Flexibility:** Fits your bike perfectly—confirm your mount type and upgrade effortlessly.
- • **Trusted Brand with 1-Year Warranty:** Ride confidently backed by BIYDOO’s quality assurance and responsive support.
- • **Universal MTB & City Bike Compatibility:** Versatile design suits mountain, road, folding, and even tricycles.

## Overview

The BIYDOO Tourney RD-TY21/RD-TZ31 rear derailleur is engineered for 6/7 speed drivetrains, offering direct or hanger mount compatibility. Crafted from durable aluminum alloy, it delivers precise and stable gear shifts across mountain, road, folding, and city bikes. Backed by a 1-year warranty, it’s a reliable upgrade for riders seeking smooth performance and versatility.

## Description

Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike

## Features

- Model: RD-TY21B-GS,bike rear derailleur. Compatible with 6/7 Speed SIS index Shifting drivetrains
- Direct Mount: The bike rear derailleur is direct mount, not hub bolt mount.Before purchase, please confirm whether the rear derailleur on your bicycle is a direct mount or a hanger mount.
- Stable Performance: Forged from high-quality and durable aluminum alloy material, adjustment is more precise, ensuring stable gear shifts for a safer cycling experience.
- Wide Application: Suitable for variable speed bikes, mountain bikes, road bikes, folding bikes, city bikes, tricycles, and more.
- Note: Your satisfaction is of utmost importance to us. We are committed to providing high-quality customer service. If you have any questions, feel free to contact us anytime, and we will provide you with a satisfactory response.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Manufacturer | BIYDOO |
| Item Package Dimensions L x W x H | 6.02 x 5.67 x 2.4 inches |
| Package Weight | 0.27 Kilograms |
| Brand Name | BIYDOO |
| Warranty Description | 1 year |
| Model Name | RD-TY21B Direct Mount |
| Suggested Users | unisex-adult |
| Included Components | NO |

## Product Details

- **Brand:** BIYDOO
- **Color:** RD-TY21B Direct Mount
- **Material:** Aluminum
- **Item Weight:** 0.27 Kilograms
- **Mounting Type:** Clamp-On Mount

## Images

![Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike - Image 1](https://m.media-amazon.com/images/I/71+BnB-ggML.jpg)
![Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike - Image 2](https://m.media-amazon.com/images/I/71bVqVoXziL.jpg)
![Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike - Image 3](https://m.media-amazon.com/images/I/61spnAaan4L.jpg)
![Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike - Image 4](https://m.media-amazon.com/images/I/61bB1MkwFDL.jpg)
![Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike - Image 5](https://m.media-amazon.com/images/I/61i44Y-Id8L.jpg)

## Available Options

This product comes in different **Color** options.

## Frequently Bought Together

- BIYDOO Bicycle Rear Derailleur Tourney RD-TY21/RD-TZ31 6/7 Speed Direct Mount/Hanger Mount for MTB Bike
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**Shop now:** [https://www.desertcart.nl/products/620149145-bicycle-rear-derailleur-tourney-rd-ty21-rd-tz31-6-7](https://www.desertcart.nl/products/620149145-bicycle-rear-derailleur-tourney-rd-ty21-rd-tz31-6-7)

---

*Product available on Desertcart Netherlands*
*Store origin: NL*
*Last updated: 2026-01-25*