The front derailleur should run parallel to the chainrings. If it doesn't, slacken the bolt fastening it to the frame and rotate it into the right position. When directly above the largest chainring, the outside edge of the derailleur should sit 2-3mm above the teeth of the chainring.
Where should front derailleur be placed?
The front derailleur cage should be approximately parallel to the chain. If the derailleur cage is rotated too far from this position, it will shift poorly. If the derailleur mount is a clamp type, its rotation can be changed. Generally, the outer cage of the front derailleur should be aligned to the chain.
What happens if front derailleur is too high?
Derailleur Alignment & Positioning
Most front derailleurs can be adjusted for height and rotation. If the cage is set too high over the largest ring, it may not perform well. Too high a cage can cause a slow shift, and can allow the chain to shift over the largest ring.
Why is my front derailleur not shifting?
Common Front Derailleur Problems. Front derailleurs may cause sluggish or inaccurate shifting because (A) the derailleur body is not positioned properly, (B) the derailleur limit screws are not adjusted correctly, (C) the mechanism is dirty or (D) the cable is damaged or improperly tensioned.
Which derailleur do you adjust first?
In a nutshell, adjust the front derailleur first, then the rear. Show activity on this post. If the derailers just need minor tweaking (they are basically in adjustment but are "not quite right") then you adjust the one that is obviously wrong, check the overall adjustment again, then again adjust what needs adjusting.
42 related questions foundHow tight should front derailleur cable be?
Holding the cable tightly so it can't slip, pull up with the pliers to remove all slack in the cable and hold it like this as you tighten the anchor bolt to secure the cable in place. It should now be tight enough so that when shifted onto the large chainring, there's no rubbing.
Why is my front derailleur slipping?
For the front derailleur, you have to apply tension to the cable to get it to move to the right ("harder gear") if the cable lengthens (or slips), by even a millimeter or two, it can cause the front tuning of the gear system to get out of whack with the result being the chain dropping to the easier gear(s).
Which limit screw is which front derailleur?
Like a rear derailleur, the front derailleur will have limit screws marked 'H' and 'L'. These screws are used to stop the cage at the extreme ends of travel. The end of the limit screw strikes the linkage, and this stops cage travel. The 'L' screws determines the amount of innermost cage travel.
Are all front derailleurs the same?
There are two different types of braze-on front derailleur interfaces: one is commonly found on road bikes, the other on mountain bikes. The interfaces are different enough that a quick visual inspection should allow you to determine which type of interface you will need.
How do you adjust the front derailleur height?
Step 1: Front Derailleur Height
- Shift the derailleur to the middle front chainring. ...
- The gap between the teeth on the outer front chainring and the lower edge of the outer cage plate should be about 1-2mm. ...
- To raise or lower the derailleur, first relieve the inner wire tension by shifting to the lowest chainring.
How do you adjust a bicycle derailleur?
While pedaling the bike, shift one cog larger by clicking the shifter lever. If the derailleur doesn't move the chain into the next cog or hesitates, add one-quarter turn of cable tension (counterclockwise on the barrel adjuster) and try again until the derailleur easily shifts into the next cog.
How do I know if my front derailleur is bent?
It does look bent, the inner and outer plates should present parallel faces to the chain. The outer plate looks like its lower aft end is bent inwards. That will make it catch the chain and may throw it inside on downshifts.
How tight should your gear cable be?
You need to pull it pretty tight before clamping it to the derailleur. Probably as tight as you can. Usually I find that's still not tight enough, so I screw the barrel adjuster down all the way before putting the cable in and then open it up until the tension is correct.
Which way do you turn the barrel adjuster?
Rotate the barrel adjuster towards the back of the bike, or clockwise if you have the cable nearer to you than the shifter.
How do you shift derailleur gears?
Left hand: Controls the front gears/front derailleur by moving the chain up and down the chain rings. These levers cause big jumps in gears for sudden changes in terrain. Right hand: Controls the rear gears/rear derailleur by moving the chain up and down the cassette.
How do I adjust the gears on my front derailleur?
Use the barrel adjuster to fine-tune the position of the derailleur. Turning it anti-clockwise will increase the tension, making it shift into the big chainring more readily. Don't forget to shift across the rear cassette as well to make sure each individual gear combination works.
Do derailleur springs wear out?
That said, derailleur springs will lose tension overtime, and pivots will get sloppier. Shifters can wear out too (if you ride enough), and most cannot be serviced back to health. But before you go sinking money into these more expensive components, best try a new cable/housing or get a second opinion.
How does a front derailleur work?
The front derailleur moves the chain between the three front sprockets. Unlike the rear derailleur, the front derailleur moves the top part of the chain, which is under tension when you are pedaling. This means that in order to switch sprockets on the front, you have to ease off on the pedals.
How do I know what derailleur I need?
If you are replacing an existing derailleur on a bike, simply count the number of cogs on your cassette and you're good to go. If your drivetrain's speed is an unknown quantity, you can count the number of steps that your shifter runs through and add 'one' to determine the number of gears your drivetrain has.
What does H and L mean on a bike?
You need to adjust the high (H) and low (L) limit screws on the derailleur. Viewed from behind the bike, the H screw limits how far the derailleur can move to the right, while the L screw limits how far the derailleur can move to the left.
How do I stop my bike chain from rubbing on the front derailleur?
If the chain is rubbing the outer edge of the derailleur cage, try increasing the cable tension using the barrel adjuster by turning it counterclockwise one quarter to one half turn at a time—increasing the tension will pull the cage out and farther away from the bike.
Which limit screw is which?
The limit screws do not control the derailleur on the sprockets between the two extremes. These are set using the barrel adjuster and tension on the inner wire. The limit screws are usually marked "H" and "L". The "H" controls the outer most limit of the derailleur, and the "L" controls the inner most limit.
