49. How To Install a Rear Derailleur

Removal and installation of a standard bolt-on rear derailleur.

IMPORTANT: Nuts and bolts on your bike should always be tightened to the manufacturer's specifications.
How To Install a Rear Derailleur
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In this tutorial we’ll learn how to replace a standard bolt-on rear derailleur.

Tools

For this job you’ll need a 5mm hex key for the derailleur’s mounting bolt, and a 2.5mm or 3mm hex key for the jockey wheels if you will not be removing the chain to clean or replace it. If you are removing the chain you may need a chain tool depending on your type of chain. You’ll also need wire cutters and a 9 or 10mm metric open end wrench, or a 5 or 6mm hex key to remove and install the rear shift cable. The last thing you’ll need is a phillips (+) screwdriver for adjusting the derailleur’s limit screws.

Rear Derailleur Removal

The first step is to shift your chain onto the smallest rear sprocket. Then pull off the shift cable’s end cap and loosen the cable pinch bolt. Remove the cable from the derailleur.

Now you’ll need to remove the chain from the derailleur. Some chains have a special connector pin that need replacing if removed, so if you don’t need to remove the chain for cleaning or replacement you can simply remove the lower jockey wheel and rotate the cage plate to release the chain. If you are removing the chain, disconnect a link and pull the chain through the jockey wheels.

Now you can unthread the derailleur’s mounting bolt all the way counter clockwise to remove the derailleur.

Rear Derailleur Installation

Before installing the new rear derailleur, apply some waterproof grease to the mounting bolt. Then thread it part way into the derailleur hanger, and rotate it clockwise to make sure the b-screw or tab is sitting behind the flat on the back of the hanger. Then fully tighten the mounting bolt.

If your chain is still on the bike, undo the bottom jockey wheel and thread the chain over the top pulley. Then re-install the lower jockey wheel. If you have removed the chain, re-route the chain through the jockey wheels and reconnect it. Search the site for tutorials on how to use a chain tool or a quick release chain link.

Rear Derailleur Set-up

Now preset the high-limit (H) screw so the upper jockey wheel is roughly in line with the smallest sprocket when viewed from behind.

Thread the shift cable back into the derailleur, pull it tight and tighten the anchor bolt so the cable flattens. Then find a bare stretch of cable and give it a good pull to make sure the cable is seated and has no slack. Then loosen the cable, pull it tight again and re-tighten it.

Now you’ll need to adjust the rear derailleur as shown in previous tutorials. If necessary, trim the cable so there is about 2 inches remaining. Then slide on a cable end cap and crimp it in place.

Tags

Discuss this topic in the Derailleur Forums

09/19 Mountech derailleurs

I've read quite a few posts in other forums about these derailleurs breaking apart while riding. I have one on my 83' le tour luxe in great condition and was interested in finding out more about it. I haven't seen any reference in posts to exactly where the derailleur was breaking apart at. Has anyone had any experience with these and what is breaking apart on them?
Thanks!... Read more >>

09/17 Suntour symetric shifters question

New to the forum and it looks like a lot of helpful info here.
Now that that's out of the way,
I have a problem locating a part for my down tube shifter. It's a flat washer that has a small hook or tab on it that sits inside the shifter. The hook part has a crack and is starting to break off. Does anyone know where I can get a replacement part for it?
Thanks... Read more >>

09/09 Problems with front derailleur.

Hi
I have just done a complete overhaul on my wife's mountain bike, here is a list of what I have replaced;
Shimano MF-TZ 31, 7 speed 14-34 mega range cog set.
Shimano FC-M 171, 48\38\28T Chain set.
Shimano RD-TX35 6\7 speed rear derailleur.
Shimano FD-TX51 front derailleur.
Shimano CN-HG40 Chain.

I have adjusted and indexed the rear mech. The problem I have is with the front mech, I can change from smallest to largest cogs OK but when I change from the largest it changes to the middle cog fine but will not go to the smallest cog no matter what... Read more >>

09/07 Convert down tube shifter to STI shifters with Campag 980 6 x 2 speed

Hi,

I want to convert my Raleigh Rapide from downtube shifters to STI shifters.

(top bike)
http://bulgier.net/pics/bike/Catalogs/Raleigh83/ral83_08.jpg

So I have Campagnolo 980 derailers, 6 at the back and 2 at the front.

(front)
http://www.retrobike.co.uk/forum/download/file.php?id=88763

(& back)
Read more >>

09/07 Front Derailleur problem/whole shifting system

Sanwa Road Bike. 10 Speed. Had for about 10 years. I only have one speed 5th gear. I know videos all over. I watch them and just can't get this thing correct. Thought I'd head here for help and I have a new Schwinn coming. That's pretty inexpensive also. Looks like a nice web site also.

Problem: Start with something simple. Getting from 5th to 10th. When I push the Front Derailleur by hand it snaps back. I can pull the lever on top of bike down to shift to 10th and the lever snaps back. If I put the bike in 10th the derailleur snaps back toward the bike causing the chain to go to ... Read more >>

08/30 Schwinn Continental Derailleur Replacements

I've recently bought a women's Schwinn Continental at a garage sale. We think it's a 1975, but we aren't sure. Anyway, I'd like to get a totally different rear (and possibly front) derailleur for it because no matter what we do, it doesn't like to switch into all of the gears. We read that the original derailleurs on the bike don't really work well with it, so we were looking at maybe a Suntour or Shimano, but we have no idea were to start or anything. Could some one give us some information that could help? Thanks in advance.... Read more >>

08/29 Buying a new rear derailleur.

Hi all, I'm a bit new to the maintenance of a bike so would really appreciate any help. I have a road bike that needs a new rear derailleur fitted.

My current rear derailleur just says shimano on it but my gears are shimano sora triple deck. I've looked online for a replacement shimano sora derailleur which are all 9 speed but mine is an 8 speed. Will this cause a problem?

Also, I've seen that you need to know the total tooth capacity. Can you just confirm how you work this out?

Thanks for any help!... Read more >>

08/27 13/23 to 14/28 rear derailleur question

Hi,

So today I ordered some new wheels for my 700c conversion. The wheels come with a 7 speed freewheel which is just what I need. However, my current cassette is 13/23 and the new one is 14/28. What adjustments will I need to make to the rear derailleur so that it will shift smoothly and accurately on the new cassette.

Jamin... Read more >>

08/27 Rear derailer refuses to travel from top to low gear

Hi,

I've encountered a very strange problem I've never had before. I have a Fischer mountain bike with shimano acera 8 gear derailer. About a week ago it suddenly developed a very strange problem, the derailer only travels part of the distance it should to give me the full gear range. Now I only get it to go to gear sprocket 2 at the low end through to sprocket 5 or 6 towards the high end.

I've tried making various forms of adjustment to the derailer, but this has only very limited effect. Has anyone here had this problem, and any ideas about how to fix it and how it... Read more >>

08/26 Help with 10 speed Freestyle

I'm a bike tech at dicks sporting goods in Bloomfield, MI and I'm having trouble with replacing the cables on an old 10 speed freestyle. I've only been working at this job for about 3 months now, so I don't have a ton of experience working on bikes yet, and I can't tell how to get the cable out of the shifter.

It looks like the cable should just be able to pop out of the end of the shifter (I have already removed the housing), but I can't get it to budge. Is there something else I need to do first before I can take the cable out, or is it just that this particular one is likely j... Read more >>

08/25 Hyper havoc issues

We just bought a hyper havoc within the last 2 months and have only ridden it a handful of times. My issue is the other night as we were riding along the chain snapped off. Looked like it broke? We just started riding again recently so we're not familiar with these new bikes at all. Do I need to buy a new chain or can this one be fixed? I snapped it back together but I just don't know if it'll last or what. Lol I apologize for my ignorance about anything mechanical lol.... Read more >>

08/25 Shimano shifter replacement question

On the weekend I crashed and managed to destroy one of my shifters. I've got an old Cannondale 105 with 105 components - double and 9 speed. I'm wondering if any other Shimano double/9 speed shifters would be compatable or do I need to try and find an old set of the 105 ST-5510?

Thanks!... Read more >>

08/23 Road bike gears not shifting at all

So I took my bike out for a ride and neither of the gears seem to shift, pressing the shift bottom (sorry dont know the name for it) next to the brakes doesnt do anything, no clicks or sounds, nothing happens.

I have no clue whats wrong with it so please help me, I'll upload more pictures if needed and do any tests

here are some pictures

[Image: pt53f8c1ec.jpg][Image: ch53f8c1eb.jp...					<a href= Read more >>

08/22 Gear shift lever replacement.

At age 43 I recently have taken up cycling, it's been about 20 years. I had found a 1982 Free Spirit 10 speed, Sears brand by Murray I think, at a junk store. $15 and everything seemed to work, couldn't pass it up. I put new tires on it and was riding, wheels fairly true, all 10 gears, no squaking or squealing, decent stopping. Then the other day, the left lever snapped off. No surprise being 32 year old plastic, I remember new bikes doing that in my younger days. So my question is, what's a good source to order this part from? I'd want to go metal and replace the whole assembly, I'm gues... Read more >>

08/22 Little string inside shifter is broken. What should I do?

Hi everyone,

I have a Trek 7000 (93/94) still with tons of original parts on her.
A few weeks ago, the rear shifter broke, not shifting to the lighter gears, but was still shifting to the heavier ones.

When I opened it, I saw that a little spring inside it was broke.

Just like the one seen here:
http://www.cs.hmc.edu/~geoff/deoredx/reductions/P2004.09.08-12.00.07-3849.01.html

I can't find this spring anywh... Read more >>

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