- Road & MTB Components
- Gears & Drive Chain
- Rear Derailleurs
- MTB Rear Derailleurs
- Shimano Deore M591 9 Speed Rear Derailleur
Sorry, this product is no longer available!
Shimano Deore M591 9 Speed Rear Derailleur is no longer available at Merlin Cycles. However you may find an alternative or updated product below.
This item was discontinued 17th November 2016.
If you require help finding an alternative to this product please contact customer services.
- Wide link top normal Deore rear derailleur
- Wide link design increases rigidity and service life
- Top normal return spring lends to incredibly intuitive operation when combined with Rapidfire shifters
- Alloy and steel construction leads to lower weight without compromising strength and durability
- Large 11 tooth pulleys are used for longer life
- Two fluorine-coated link bushings for low-friction operation
- 8- and 9-speed compatible
- Compatible with 28-34T low sprocket
- Average weight 299 grams
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This rear mech is good quality and easy to fit. Always bought this type of mech because they last and are very robust. Price and delivery are good as well
My old rear mech was very worn, fitted this new one & the changes are very slick & smooth now. The price from Merlin was the best I could find & speed of delivery impressive.
Upgraded from an Alvio. Chalk and cheese.
Upgrade from Alivio rear mech destroyed on the trail. This solved the vague shifting I'd been putting up with since I bought the bike! Very quick to install and set up. Highly recommended
This was a straight swap for a damaged rear mech that had lasted me an incredible 11 years. As always top quality service from Merlin, I vowed to use them as much as possible and I`m finding all my cycle needs are all stocked here. Quality product as always.
I would not have thought it but this mech runs better on my drive train than my old XT did before it was damaged. Top marks to Merlin too for good advice before my purchase and excellent delivery time
A very well priced mech with features which were just available on higher end mechs a few years ago. Seems strong and just the job for an everyday bike.
Used this derailleur with a SRAM 1070 12-32 cassette and Ultegra 10sp shifter to add a lower gear. Shifts as smoothly as the Ultegra derailleur it replaced. Much cheaper to go this route than to upgrade to Ultegra 6800 just to add a 32.
Great rear mech accurate shifting easy to set up, a massive improvement on my old Alivio 8sp. Great price and quick delivery from merlin too.
Great quality cheap mech! Not quite XT but very good for the money. Using it on a 10 speed mtb cassette with 105 shifters as the dyna-sys mechs were not compatible. Shifting not quite as slick as the original 105 mech but still works fine.
Great rear mech at a great price. Get yourself a brand new cable, too and once adjusted correctly, it shifts like a dream.
Together with a new cassette, it really breathes new life into a worn drivetrain.
Excellent quality and price.
Mr D K Roberts
For the price it is an excellent derailleur and again great savings when purchased from Merlin
It's very good.
It's very fast.
I love it! Much better than my old Shimano Alivio's rear mech.
Good value for money product as a direct replacement for the worn out Deore mech on my bike. It is becoming increasingly difficult to obtain these older parts as Shimano have introduced newer lines.
Good value rear mech. Fitted it to a road bike so that I could use a cassette with a 30 sprocket. Runs well with 8 speed down tube shifters. I understand that newer version of Shimano MTB rear mech will not work with road gear levers.
Cheapest I can find and best delivery and customer service I have found. Thankyou will be back soon
The perfect replacement, easy to fit, and the cheapest price to be found.
Bought this to go with a 10/34 cassette on my road bike (lots of steep hills locally & I'm getting older!)
Reasonably easy to fit, looks good and works well.
Arived very quickly after the order - good service.
A replacement for a very worn out Deore rear mech on my Sirrus Sport which has done nearly 5000 miles. Absolutely brilliant for the money and shifting is smooth and accurate again. Service from Merlin was faultless.
It's a rear mech, it changes gear at the rear. It looks good in black because everything does. What makes it special is it's the cheapest on the web and it was delivered the next day by Merlin, first class as per usual.
I purchased this item to get the long arm to put onto an Ultegra 10 speed derailleur, which had the same pin type mount fix.
It allows me to use a 36 tooth rear cassette with a compact two speed crank with no problems.
I just swap the arms.
There seems to be two different types of locks to hold the derailleur arms to the bodies, even for the same named derailleur.
One type has a pin at 90 degrees to the shaft and the other has a slip-over arm with a bolt through the swinging arm, so please be careful.
The arm is longer than the 'GS' models of 105, Ultegra and Dura-Ace.
The Deore body is not used.
Although ALIVIO was used until now, the gear became smooth after changing into DEORE.
excellent rear mech for the cost - looks good, easy to fit and smooth changing once on; would happily purchase again