49. How To Install a Rear Derailleur
Removal and installation of a standard bolt-on rear derailleur.
In this tutorial we’ll learn how to replace a standard bolt-on rear derailleur.
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.
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.
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.
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.
I'm upgrading my Dahon MU SL folding bike from 9 to 18 speeds by adding a 2nd chainring in front.
I want to use an SRAM X9 or X0 trigger shift as the bike has a flat bar instead of a bull/drop bar, and the bike is currently equipped with X9 shifter/rear derailleurs.
The crank will have a 53T and 39T chainrings and are not compatible with SRAM X9 front derailleurs (48T max) due to the big 53T chainring.
I'm thinking of using a either SRAM Apex/Rival or Shimano 105/Tiagra front derailleurs, but want to use an SRAM X0 or X9 2 speed trigger shifter.
... Read more >>
Hi, I have just bought a custom built Azonic gravity frame downhill bike but there is a problem with the rear derailleur. The main pivot, as you can see from the picture, has no tension so does not pull the chain at all and it is, therefore, way too slack. Does anyone have any suggestions on how to fix this or do I need a new one. Thanks... Read more >>
I am thinking of buying a bike with 50-34 compact with 12-32 cassette
Will I be able to use Ultegra electronic shifters with this setup?
Reg... Read more >>
Hi guys, I thought this was going to be a little less hassle than it is turning out to be. I replaced both STI levers on my bike to Tiagra 10 speed. RHS is working fine job complete. However the LHS shifter moves the chain sweetly up on to the large chain ring but when I try to move it back down, the shifter feels tight but it eventually snaps the chain back into the small chain ring. It's just not moving between rings smoothly. All cables inners and otters have been replaced.
What could be the issue?
Thanks in advance
Mark... Read more >>
So I just got a new BTWIN Original 5 and i'm the kind of kid that is sort of reckless with my bike my parents might say. I power up curbs i do wheelies i jump off at high speeds, stuff like that. Well one night i was riding through town and suddenly the chain came off and the gear cable just came out of the gear shifter. Someone stopped to help me with the chain but didn't know how to fix the cable and since he was french i didn't understand him so i went along my merry way. I had been experiencing some issues before this though also. When i would shift to the highest gear, it wouldn't switch ... Read more >>
I'm new to this forum and tuning bikes in general. I bought a bike which has 8-speed on the shifter and the derailleur moves with the shifter to 8 positions of course. However there are 7 sprockets on the rear.
Is this a problem? While riding I do find that I can't use certain gears as the pedal clicks violently which is quite dangerous. So I've been staying in the safe-range (which is in the middle gears, or high for both front and back).
Is this fixable without having to buy anything else?
thanks would really appreciate anything on t... Read more >>
Need some advice if possible.
Removed broken Simplex red label derailleurs front & rear. Rear any 10 spped will work as I read online probably better than the Simplex Prestige that was original.Schwinn Caliente 10 speed donor bike removed the Shimano Tourney Rear Derailleur and Installed it.
The front is a bottom pull so limited somewhat to compatibility. Found that a Suntour Spirt (not spirit) will work as it is a bottom pull. I know I could jump up in the Huret All metal French derailurs but Suntour parts are readily available and much cheaper. Clamp on same style.
Brought my new road bike online and had it delivered just yesterday. Came mostly assembled with just the front wheel to attach and handlebars to straighten out.
In the process of self bike fitting I noticed when just going up and down the road that the front derailleur was not set up correctly and the chain was rubbing when using the 2 biggest cassette rings. In finally getting this sorted, which was easier said than done, my friend who helped me noticed that the derailleur barrel adjuster didn't appear to change the cable tension in any way. Now at one point during my failed... Read more >>
I have a dunlop signature series Raider mountain bike. The three speed gear shifter on the left no longer catches and I can only use gears 13-18.
the gear shifters have no name on them but the derailleur has the dunlop logo on it. I have tried to contact dunlop with no luck. Do you have any idea which gear changers are compatible with this bike
Greg Moran... Read more >>
Im having a problem with the rear derailleur. As I'm riding the mountain bike and pedaling everything seems to be fine. When I stop pedaling and just coast it, the derailleur lifts up close to the bike frame and pops back in place. Sometimes when it does this the chains slips into other gears. Not sure whats wrong with it or if its something I could fix with some simple adjustments. Help. Thanks.... Read more >>
Hello all!! I have an old Murray and the rear derailleur needs replacing. Well, there appears to be nothing on the net about what is comparable? The one that is on there now was made by Frontier and I could find nothing online about replacement parts. Wondering if any of you guys have some suggestions??... Read more >>
So I have an odd problem,that leaves me helpless. I welcome any ideas. I just purchased a new(to me), but slightly used, MT bike. Cannondale Adventure 400. The bike has a Shimano Nexave front derailer over 3 chainrings. And a Shimanno Deore rear derailer operating an 8 cog cassette. My shifters are SRAM MRX PRO 1-8 on the right and 1-3 on the left. This bike is basically brad new but was stored indoors for several years.
Here's my issue. The bike shifts absolutely perfectly and quietly,however no matter what adjustment I have made, using the right shifter, I can easily shift to an... Read more >>
I have an old Takara road bike with suntour shifter and derailluers and am considering upgrading to full shimano group. I would like to find some good shimano 600 units. Anybody got suggestions?... Read more >>
I recently purchased a bike from someone and the front derailleur does not work. I am sorry, but there is really not much i can tell you about the problem. I don't want to mess around with it because it didn't turn out well the other time. If someone could give me a few suggestions, that would be nice. If it helps the model of the bike is the 2009 giant tcr alliance 1
-Thank you... Read more >>