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Free UK Shipping Over £50 & Easy Returns


Free UK standard shipping on orders over £50
The Shimano GRX RD-RX820 is a high-performance 12-speed rear derailleur designed specifically for gravel riders seeking precision and durability. Featuring the innovative Shadow+ technology, this derailleur reduces chain bounce, ensuring a stable and quiet drivetrain even on the roughest terrain. Its low-profile design not only enhances shifting speed but also protects the mechanism from damage, making it perfect for challenging off-road conditions.
Crafted with high tolerance cold forged aluminium link plates and body construction, the RD-RX820 balances lightweight performance with exceptional strength. Compatible with 12-speed Hyperglide+ chains and supporting a wide gear range up to 11-36T, it offers smooth, reliable shifting tailored for double chainsets. This component elevates your gravel bike’s transmission, blending rugged reliability with optimized gearing options for superior control and efficiency.
Is this derailleur compatible with Shimano 12-speed road groups?
It is designed for gravel use and optimized for 12-speed Hyperglide+ chains, so compatibility with standard road groups may vary.
Can I use this derailleur with a single chainring setup?
No, the RD-RX820 is intended for double chainset configurations only.
Stock Status Instock - Instore - Item Usually shipped or available for shop collection, within 48 hours (Mon-Fri)
Instock - Supplier Warehouse - Item is held in Suppliers Warehouse, Depending on the the supplier transfer time can vary from 24 Hours to 14 Days for item held in European warehouse.
(over festive periods some suppliers shut from 24th Dec-2nd Jan so orders can be delayed through this period.)
Brands held in European website include Trek, Bontrager, Electra, Wahoo, Rapha. For up-to-date transfer times please call customer services on +44 (0)1782 768622
Most out products are shipped by FedEx, providing unprecedented reliability and speed. Lightweight Spares below £25.00 value have a Royal Mail postage option, which is sent via Tracked 48 service. - £2.99
Shipping on all Domestic Orders over £50.00 (excluding bikes and home trainers) for delivery within the UK is completely FREE!
Bike and Home Trainers and oversize Goods £15.00 - FedEx
White Glove Bike Delivery - our white glove option has your bike personally delivered to you by a fully trained Mechanic and Bike fitter - £99.99
(Certain bikes will only have this option such as Cargo Bikes)
To Qualify for FREE Shipping:
In some cases, we may ship items out with another courier, depending on the status and availability of items ordered. (Customers will not be charged more and will be refunded any unused postage cost) If part of an order is cancelled and the total drops below the £50.00 free postage, a postage charge may be taken.
Delivery costs will be clearly stated on the checkout page, though you will need to register (to provide your delivery address) in order to see the delivery costs.
If you have any questions about delivery charges, times or none delivery please do not hesitate to get in touch by email:store@swinnertoncycles.co.uk or by telephone on +44 (0)1782 768622. Handling is normally 48 hours, but at busy periods this may be extended but we will endeavor to process your order within 5 working days. Please bear in mind in some cases orders can take longer to process, please contact us for more details.
You may return most new, unopened items within 30 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.