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Btwin 10-Speed Rear Bike Derailleur

Sale price: $20.00 Regular price: $25.00

Long screed rear derailleur compatible with Shimano and Btwin 10-speed drive trains for fluid and precise gear changes.

Color: Select a color
Size: Select a size
Sale price: $20.00 Regular price: $25.00

Free shipping over $49

Final Sale: No returns or exchanges

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San Francisco, 735 Market St. Options

Select an available color and size to see options.

Model: 8402926

Product Features

A photo of the Btwin 10-Speed Rear Bike Derailleur in use

Btwin 10-Speed Rear Bike Derailleur |

Long screed rear derailleur compatible with Shimano and Btwin 10-speed drive trains for fluid and precise gear changes.


Only compatible with Shimano and B'Twin 10 speed shifters.

Questions & Answers

Product Customer Reviews

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35 Reviews
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Btwin 10-Speed Rear Bike Derailleur,black
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Budget replacement does the job

See title!

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So far so good...

Although it feels a little fragile... Good for the price.

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Poor quality materials

The derailleur broke near the hangar bolt whilst riding mid corner. It immediately caught in the chain and cassette causing the back wheel to lock, causing me to crash the bike. I get the bike maintained at Decathlon and the cassette, chain, front and rear derailleur were replaced less than 6 months ago, and I have done no more than 350 miles mostly on road during the lock-down. I see that another customer reported a break in the same place. This item is dangerously under-engineered and should be pulled from the shelves.

Worked with a 13-39 cassette, but the arm broke!

A sudden clean break of the arm next to the hanger bolt when changing between mid-range gears. I was not using great force on the pedals, and there were no signs of anything jamming. Was it metal fatigue?


Precise shifting but on heavy side . No complain for the price. Use on my mtb 1x10 40t

Hi Florencio!

Thank you for taking the time to review our products. I am pleased to hear you enjoy using this 10 speed bike rear derailleur.

Your feedback matters as it allows us to further understand how you use our products and services and how we can improve to serve you better. 

We look forward to more of your reviews and sharing! In the meantime, keep sporting on, and we hope to see you in our stores soon!

Stay Healthy, Be Sporty!



V popisu je 42 zubů převodů, ale po dodání jsem to namontoval na kolo a 42 zubů to opravdu nezvládá, v popisu maximálně 40 zubů. Ihned jdu reklamovat a mám sto chutí vás nahlásit za klamání zákazníka. Naprostí amatéři. Na které se nedá spolehnout

Dobrý den, Jakube,

velice děkujeme za Váš čas věnovaný recenzi tohoto produktu. Každá zkušenost je velmi cenná a pomáhá nám s vývojem nových modelů.

Je nám líto, že produkt neodpovídá udaným parametrům. Spojili jsme se s kolegy z oddělení cyklistiky a tento měnič je opravdu na 40 zubů. Bohužel, jedná se o chybu na webu, kterou jsme předali kolegům k opravě.

Ráda bych Vás proto pozvala na Vaši nejbližší prodejnu Decathlon, kde můžete produkt vrátit či vyměnit za jiný.

Omlouváme se za komplikace.

S láskou ke sportu,


Compatible con Shimano

Un buen cambio de 10v fácil de ajustar y compatible con mandos Shimano, en mi caso el piñón fue de 11*36 y aún le queda para subir, funciona muy suave, lo recomiendo, saludos.

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De momento perfecto. Ya veremos como envejece

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Par contre mon fils a fait une erreur pour 1 virement il a fait le versement sur 1 référence de commande et il n a pas encore reçu le remboursement et cela fait 1 mois

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Ce dérailleur est compatible avec les groupes 10 vitesses shimano d'après 2015 soit pour le groupe tiagra 4700 seulement, Contrairement à ce que le service D4 m'ait répondu

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Nous vous remercions pour cet avis sur le dérailleur arrière 10 vitesses Decathlon

Nous sommes désolés que ce produits n'ait pas convenus à votre vélo et nous le regrettons.

Vous pouvez venir échanger ou rembourser ce dérailleur dans le Decathlon de votre choix en vous munissant de votre carte Decathlon ou ticket de caisse.

Dans l'espoir de vous revoir très vite, nous vous souhaitons une bonne journée.

Romain Gerin Moniteur Rockrider/Riverside Belgique



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Monté sur mon vélo…

Monté sur mon vélo taf avec la manette ad hoc decathlon, et ça marche bien pour le prix. Monté avec une cassette 11/40.

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Peu utilisé depuis le…

Peu utilisé depuis le changement

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Additional Product Information



  • 80% Aluminum
  • 10% Polyamide 6. 6
  • 10% Acetate


Screed length: Length Maximum teeth: 42 teeth Min teeth: 11 teeth Aluminum body



Superior quality. Unbeatable prices.

For 40 years, Decathlon has delivered the best value in the retail sports industry by offering high-quality, sustainable and cost-effective products.

Decathlon makes the difference
  1. product-research

    Research and development

    delivers high-quality cost-effective products

  2. State-of-the-art production processes

    minimize manufacturing costs

  3. Optimized supply chain

    reduces retail prices

  4. laptop-checkout

    Minimal retail footprint

    lowers overhead and indirect costs


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