FREE SHIPPING on orders of $50 or more.* Same day shipping before 3PM Pacific.
Questions? Call our experts!
Click to zoom

Ultegra RX RD-RX800 11s Rear Derailleur

Mfg PartNum:IRDRX800GS
  (4 customer reviews)
Sale Ends
Purchase this popular item
today and save 5%
Earn $5.22 in Rewards credit. Click to learn more.
This color/size is not eligible for Rewards points
Out of Stock
Save 5%
MSRP $109.99
This item is currently out of stock. Click Notify Me to receive an email when the item becomes available.
InstantPrice MatchWhat is this?
Qualifies for Free Shipping!

Shimano's Ultegra RX RD-RX800 11s Rear Derailleur features a clutch design that eliminates chain drop on rough terrain and provides a better interface with a Shimano 1x set up.

B-Stock - This product has one or more B-Stock units available. These units can be purchased at a discount (see option select). B-Stock units were returned from other customers and may have missing or damaged packaging materials. These units are otherwise as new. The full manufacturer warranty applies. Click Here for more information.

Ordered by Most Relevant First
5 stars
4 stars
3 stars
2 stars
1 stars
So far, so great
by Dolan
Competitive Racer
3 of 3 customers found this review helpful.

So, it adds 40 grams over a standard Ultegra derailleur, but if you're looking at this, you know it's well worth it. After a number of CX races and gravel rides with it, the clutch noticeably works in the sense that you don't notice the chain slap you did before, and you don't notice your chain dropping. There's a little bit more friction, and shift effort is a tiny bit higher, but well worth it for the peace of mind this derailleur gives you.

Reviewed 11/2/2018
Was this review useful to you? Yes/No
Thank you for your feedback.
One of my favorite upgrades
by ScottieMo
Daily Commuter
New England
3 of 3 customers found this review helpful.

Conclusion A clutched rear mech will probably become a standard for everyone but triathletes.

I bought this upgrade to replace a dying 6800 rear mech. I am a daily commuter, mixed surfacelong ride weekender. Shifting is crisp, but the real pleasure has been a lack of chain slack or slap. My chainline stays tight no matter where I'm riding. I ride over potholes, train tracks, dirt trails, fire roads and overall poorly maintained roads. The other nice part is that the cable is now tucked underneath everything rather than to the outside in the 6800 series, so it should take less abuse. Adjustments on the barrel adjuster are easier as well.

Reviewed 11/5/2018
Was this review useful to you? Yes/No
Thank you for your feedback.
Very smooth
by Otto Von K

Works as advertised. Im primarily a road cyclist but love that I can tighten up the chain for excursions on gravel and modest dirt tracks.

Reviewed 8/5/2019
Was this review useful to you? Yes/No
Thank you for your feedback.
Great upgrade
by Anonymous

Needed a replacement for my worn 105 derailleur and wanted a clutch. This fit the bill, shifts are crisp, no complaints.

Reviewed 7/1/2019
Was this review useful to you? Yes/No
Thank you for your feedback.

Articles will open in new tab.

Comparing bottom bracket types and standards.
You wanna go fast? Join the ceramic revolution!
Make your upgrades count. Here's the equipment that will help you ride your bike faster.
Campagnolo vs. Shimano vs. SRAM: demystifying groupsets.
What to consider when selecting a crankset for your road bike.