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How 2 adjust xtr derailleurs 4 a smoother shifting

12 years 5 months ago #486 by matt9210
Wow! thanks Julien! for that very detailed and technical answer.

I'll definitely print and save this one for future use as well.

thanks again!
:)

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12 years 5 months ago #485 by julien
If all your shifting line is new – shifter, cable, hosing, derailleur – and the shifting isn't smooth it means that your cable tensions isn't right.


Adjust your derailleur:

1- Release the shifting line

Shift in order to get your derailleur in the lowest position.
Some derailleurs are up-rise, most are low-rise: this means the derailleur's spring pools it towards the highest gear or the lowest one (most common).

2 - Release the derailleur's screw that holds the cable in order to let the cable slide

3 - Jockey wheel adjustment
Check the jockey wheel lateral alignment with the lowest cog, adjust with the adjustment screws if necessary. Pull manually the derailleur to the highest position and check for alignment; adjust if necessary

Check for the jockey wheel vertical adjustment with the largest cog:
You don't want the jockey wheel to collide with the cassette - you don't want it to be to far off the cog neither
Use the adjustment screw positioned just bellow the derailleur's mounting bolt to add or release the derailleur's tilt. Get the jockey wheel 5 mm above the largest cog

4 - All elements in correctly positioned
Check the cable tension adjustment screw on your shifter. Bring it back to the lowest position then unscrew 2 turns. This will give you some slack to make fine tension adjustment if necessary.

Check all your hosing ends and make sure all cable ends are well pressed in the cable caps and position tightly in the frame's cable mounts.

Check that the derailleur is properly lightened against the derailleur's drop out


5 - Adjusting the cable tension
Pull the cable from behind the derailleur's cable tightening screw and tighten the cable. Make sure you're not pushing the derailleur inward while tightening.

Now check the cable tension. While the derailleur is still on the lowest gear you must have absolutely no slack in the cable. Check the cable's slack on the cable line running against the frame (for most bikes).
Adjust the tension with the shifter's adjustment screw until no there isn't anymore slack on the cable line.
Your derailleur must not move up while adjusting. If it moves up - even slightly - there is to much tension.

Check the tension with the shifter: your derailleur must move as soon as you apply pressure on the derailleur's lever.

6 - test your shifting
manually test your derailleur to see if the gears are shifting well.
Don't test the gears with your bike upside down. Best way is to get on the side of your bike, brake with front wheel and push on the bar to elevate the back wheel, pedal with on foot and shift at the same time (it sounds acrobatic but it's possible!).

If you have properly adjusted the cable tension prior end the shifting should be butter smooth.

Now get on your bike and go for a spin. Simulate a hard climb by using your front brake so you'll see if your shifting works well under high tension.

7 - Trouble shooting
You can do all the above and it still doesn't work well, check for the following:

A - check that your wheel is properly tightened.
B - check all your chain links - a link may be broken or damaged
C - check each teeth of your cassette's cogs
D - check that the derailleur hanger / drop out isn't bent or warped - High quality derailleurs almost never warp, you need to hit them had against a rock to bend them and, still, it's most of the time the hanger that breaks before the derailleur itself

E - If the chain skips when you're riding: check for your chain ring teeth first. if they look like shark thins your must change the rings, chain and cassette.

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12 years 5 months ago #476 by matt9210
Hi there, anyone who could help me how to adjust those derailleurs so that i can have a smoother shifting...i just bought a 2nd hand mt bike with rapid fire xtr'08 shifter/derailleurs...i see these adjustment screws but dont know how to tweak them to get my desired result.

thanks
matt

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