1. How to Adjust Your Rear Derailleur
Applies to most 3-chainring derailleur systems. Adjust your Front Derailer
Adjusting your rear derailleur can be frustrating. I’m hoping that this tutorial will help you understand how each component of your derailleur works, and how to set up and adjust it properly. Once your derailleur is set up correctly, most future adjustments can be done by hand. Let’s get started!
Almost all modern derailleurs function the same basic way. They are designed to move (or derail) the chain from one sprocket to the next. The upper guide pulley (or jockey pulley) moves the chain in both directions. For instance, when you want to climb a hill, you shift down to a lower gear. This pulls the shift cable and forces the guide pulley to change to a bigger sprocket. When you want to go faster, you adjust the shifter to a higher gear. This releases shift cable tension and allows the derailleur springs to pull the guide pulley back down to a smaller gear. Each time you shift gears, the length of chain changes. The lower tension pulley is spring-loaded to take up this slack.
There are 3 adjustment screws – the B-Screw (B-tension adjustment), the H-Screw (high gear limit stop) and the L-Screw (low gear limit stop). Adjustments on these screws should always be made in 1/4 turn increments.
The B-Screw controls the derailleur body’s angle in relation to the sprocket-set. Shift down to the largest sprocket and check the distance between the guide pulley and the large sprocket. If the guide pulley is rubbing on the sprocket, tighten the B-screw clockwise to increase tension and move the pulley away from the sprocket. If there is a large gap between the pulley and sprocket, loosen the B-screw until the pulley rubs the sprocket, and then tighten it until it just clears.
The H-Limit screw high gear limit stop prevents the guide pulley from shifting any further past the highest gear and into the axle. In order to adjust it properly there must be no tension on the lower inner cable. If you feel tension, loosen the cable adjuster until there is none. Now check from behind how the chain is riding on the smallest sprocket. If it looks like it wants ride off into the axle, tighten the H-screw clockwise until it lines up. If it looks like it is rubbing on the next gear, loosen the screw until the chain is nicely centered on the sprocket. Now re-adjust the cable tension until the derailleur shifts smoothly down to the next gear.
The L-Limit screw prevents the guide pulley from shifting any further past the lowest gear and into the wheel spokes. Shift down to the lowest gear, step behind the bike, and check how the chain rides on the sprocket. If it looks like it wants to ride into the spokes, tighten the L-screw clockwise until it is centered on the sprocket. If it looks like it wants to shift down, loosen the screw until it lines up. As an extra precaution you can use your thumb to gently push the derailleur body and make sure the chain will not run into the spokes, as this could obviously have a nasty effect on both you and your bike.
The cable tension adjuster defines how far up or down the derailleur moves. Step back so you can see the chain and sprocket alignment, and then through the gears in both directions, first shifting up two and down one, and then down two and up one. The chain should look centered on each sprocket. If it is rubbing on a larger gear it means there is too much tension on the cable. Loosen the tension by turning the adjuster clockwise. If it wants to jump down to a smaller gear it needs more tension. Increase the tension by turning the adjuster counter-clockwise.
You can also use sound to check the adjustment. There is always a base-level of noise that can be heard in every gear. This noise will increase in a slightly different way depending on which way the tension is out of adjustment. If there is too much tension you will hear a metallic rubbing sound, but if there is too little tension you will hear a clicking noise as the chain tries to jump to a smaller sprocket. There is usually a cable tension adjuster on your shift lever. With practice you will be able to make small cable tension adjustments while you are riding.
Now that the derailleur is adjusted, always apply a drop of lubrication to the derailleur’s many moving parts. This will help prevent wear from dirt and rust, and it will keep your gears shifting smoothly. Wipe away any excess lube and take your bike for a test ride to make sure all the gears are working smoothly.
That concludes our tutorial on rear derailleur adjustments… have fun!
I don't exactly know how it happened. I've been trying to fix it for days but nothing works.
So let's say you had a 1-9spd derailleur:
If we would want to shift to the biggest cog we would go to the 1st gear, and if we would want to shift to the smallest cog we would go the the 9th gear. BUT that's not the case in my rear derailleur. I could only go to the 2nd smallest cog, and if I would want to shift to the biggest could I would only have to shift 8 times, this means that I would have 1 more shif... Read more >>
i dont know whats really going on but when i was riding my $300 swiss mountain bike i took a brake then got on and tried to peddle. it spawn around w/o catching the back tire. i checked to see if the chain was on, it was. i was having very slow reaction with the front gears with alot of noise before this. i have not used this bike no more then 4-6 times.
if anyone can help thanks. if i can repair it my self i would rather do that since i dont have cash for a repair person..
(but i did notice it started to catch when i go down the drive way (going somewhat speed... Read more >>
I'm a real novice at this so please make allowances! I was having trouble (front derailleur) shifting up from first to second. When I flicked the shift lever into 2nd, the cage would move across seemingly correctly, but the chain would struggle, make a lot of noise and refuse to shift up. If I pushed the shift lever over a little more - towards 3rd - and held it for a couple of seconds, the chain would move up on to 2nd position and stay there OK. I tried to correct this by increasing the tension a little on the shift wire. The result of that was that it shifts up to 2nd correctly, but wo... Read more >>
I'm re-bearing, lubing, and overhauling my wife's 1969-70 Gitane Grand Sport Mixte, and I'm showing here the 'status' of the re-build... Expenses so far: ! $40.00 if I split the cost of tools in half!
Overall she's happy with the improvements in bearings and lube, and she's 'buying' the improvements in the braking system that hasn't arrived yet... but..
As only a wife can do... She says: "You know, I like the location: (Stem Shifters) of what you have on 'YOUR BIKE', and wish I had the same on: "My Bike"...... I have to reach too far to change gears..... Read more >>
Looking the bike over for needed parts, this one is the most obvious...right (rear) shifter pod's indicator lens is gone. It's an older 18 speed Gary Fisher Tassajara with Shimano Deore shift components...dual lever (rapid fire?).
Left pod is numbered 3 2 1 from left to right. Any suggestions on what to look for as a replacement? Plan on replacing both cables, etc. while I'm at it.
Thanks in advance!... Read more >>
Hi I have a Orbea Onix T105 Road Bike which is 10 speed but would like 11 speed, is it a nightmare to do or do i just buy 11 speed cassette and switch it over ?... Read more >>
Hi, I just buy New Shimano XTR m980 shifters, I took it off from the box and tried to shift up and down. I realized that it's so hard to downshift the right shifter. Other things work amazing.
Would anybody tell me how fix that?... Read more >>
I've just gotten my 1980s road bike running again. I'm loving it, except that after over a decade of integrated gear levers, I'm finding the old-school stem-mounted friction levers quite awkward. I've just become too used to being able to change gears while braking, which feels essential for manoeuvring in real-life city traffic.
I'm wondering how realistic a task it would be to upgrade them to use combo style levers. I know I'd probably have to replace the entire gear system, but I think it'd be worth it. But do indexed gear systems take up more space on the a... Read more >>
I bought a set of Aluminum with Ball Bearing Pulleys for my early 80's Peugeot. But before I could receive them, my Wife's 1970 Gitane pulleys broke/crumbled on a ride.. Both Gitane & Peugeot use similar Simplex systems.
They were the ONLY 10 Tooth 6MM pulleys I could find.
When I got them this past weekend, I put them on the Gitane, but found the shim type pulleys were 10.5MM thick, and the aluminum BB pulleys were 6.5MM wide. Chain rubs against side mounts. I found M6 Stainless Steel washers, and put one on each side of new pulleys.. Chain clears the s... Read more >>
Currently going through a DIY upgrade of my road bike. Already made the mistake of trying to turn a 9 speed into a 10 speed but am too stubborn to go back and it's kind of fun to learn how it all works. I now have an Ultegra 6700 10 speed cassette and need to pair it with a new 10 speed shifter. I have been reading about actuation ratios and want to make sure the shifter is compatible. Would a Shimano 105 5700 STI lever fit with this 6700 series Ultegra cassette? Also would I need to upgrade my rear derailleur which is a 105 9 speed or could it do in a pinch?
Thanks... Read more >>
I recently purchased a new 2013 BMC Race Machine with a full Red grupo. Despite everything I had read about the Red Yaw FD and its ability to handle the entire gear range without trimming, I experienced chain rub. So, I decided I would simply take the time to learn how to adjust the FD myself.
I made several mistakes, and I would love any and all assistance:
1. I neglected to tighten the inner limit screw so that the FD was over the big ring, prior to releasing the cable. My understanding is that, having done this, it will be very difficult fo... Read more >>
OK, so a while ago I noticed to get into the lowest gear (largest sprocket) on the rear I had to apply extra pressure onto the shift-lever.
Now my bike does not even get past fourth gear, this is whilst it is on supposed 1st gear (on the shifter). At the moment it only has a range of 3 available sprockets to use. Also, on the gear shifter, it only goes from 1, to 2, then only just onto 3 (it feels extremely weak, rather than 'clicking' like the front gear shifter does), the rear shifter is not able to go into 4.
I decided to open up the rear shifter and see if there was anything w... Read more >>
Hi, whenever I've got a 6 speed mountain bike, but whenever I switch into the lowest gear, the chain slips off of the freewheel into the frame and is a paint to pull out again. When I put the bike up into the stand, it switches to lowest gear fine without coming off at all. It seems the pressure of my feet on the pedals makes it slip off. Just wondered if you had any suggestions? thanks.... Read more >>
I am trying to upgrade my 50/34T 105 chainset to an Ultegra 6800 46/36T system with all the appropriate 6800 components
Unfortunately there is not enough adjustment on the braze on front derailleur to enable me to achieve the recommended 1 - 3mm gap between the top of the big ring teeth and the bottom of the derailleur. The closest I can get is 4.5mm due to the smaller diameter of the 46t chainring.
I am not sure how critical this is but if it is critical to the smooth working of the system then the only solution I can see is to buy a new 50/34T Ultegra chainset which I don't reall... Read more >>
My son Supercycle 1800 has Falcon FIS 6 speed thumb shifter, which is stuck in 2nd gear and its lever is also broken.
I would like to replace it but could not find anything which worth cost, especially which is with in my rice range ( as the bike itself is not expensive)... Most of the time cost goes up because of shipping cost to Ontario, Canada.
I was wondering if someone could tell me what is compatible with Falcon Derailleurs? As that will help me pick alternates for thumb shifter..
Thanks in advance... Read more >>