Shimano Deore M591 9 Speed Rear Derailleur

Description

The Shimano Deore M591 9-speed rear derailleur is a proper and reliable derailleur from Shimano's mtb / touring series. This derailleur will provide you with unlimited cycling joy for an affordable price.

Technology

• Wide-link-design for more stiffness and longer lifespan
• Best combined with Rapidfire shifters
• Cage length: SGS long cage
• Capacity: 45T
• Largest possible sprocket: 34T
• Type: Top-Normal
• Number of gears: 9-speed
• Weight: 315 grams

Assembly

Loosen and tighten the gear cable.
To loosen and tighten the bolt with which the gear cable is attached to the derailleur, you need a 5 mm Allen key. You can find these here.

Removing the chain.
Before you can remove the derailleur, you will also have to remove the chain. How to do this, you can read here. You need a chain tool for that. We have these here. Make sure you buy one of the right brand and the right number of speed.

Use assembly grease for mounting.
If you are going to mount the new rear derailleur, it is best to apply some mounting paste to the threads of the derailleur hanger. You can buy this aseembly grease here.

Assembling jockey wheels.
To mount jockey wheels you need an Allen key of 2.5mm or 3mm. A handy Allen key can be found here:

User tips

Skew derailleur hanger?
A problem that crops up often is a skew derailleur hanger. It can happen if the derailleur knocked into something, for example in the case of a fall on the bike. Luckily it can be fixed! You can read more here.

Clean the jockey wheels well too!
Just like the chain, the jockey wheels on a derailleur get super dirty. As a result the shifting is not as good and it does the lifespan of your derailleur no good. For that reason, it's a good idea to clean the jockey wheels at the same time when you clean and lube your chain. Do this by running a cloth along the jockey wheel while gently turning the chain. Of course it gets to a point where the jockey wheels are worn out. In this blog post you can find out more about when jockey wheels should be replaced and what you'll need.

Find out more on our Blog