Gear indexing w/barrel adjuster - which direction?!

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Hi,

I'm about to attempt to index the gears on my bike and am a bit confused.

The instructions in my Haynes manual say to turn the barrel adjuster "away from the bike frame to tighten the gear cable and encourage the derailleur pull the chain up to the bigger sprockets" and "towards the frame to loosen the cable and allow the chain to move down the cassette to higher gears more easily". This seems to make sense according to the 'righty-tighty, lefty-loosey' edict that my dad taught me as a boy...

But then watcthing this video he clearly does the opposite - turning the adjuster in towards the frame to tighten the cable, and away from the frame to loosen it.

So which is correct?! Am guessing it must be the video as it's obviously working for him!
He uses 'clockwise' and 'anti-clockwise' to describe his actions but this kind of adds to the confusion as whether the turn you are making is clockwise or anti obviously alters depending on whether you are behind the mech or in front of it when adjusting it!

So if someone can please confirm whether it's a turn of the adjuster away from the frame or towards the frame to tighten I'd be very grateful. Thanks :-)
 

Tim Hall

Guest
Location
Crawley
To tighten the cable you need to turn the adjuster so the path the wire has to take is longer. This means you unscrew the barrel adjuster, so the path is longer by however many threads you unscrewed it. How that fits in with away from the frame or towards it I don't know.
 

winjim

Smash the cistern
The confusion could come from the positioning of the mech within the frame, meaning that towards the frame actually means turn the adjuster outwards, to the right, which would tighten a screw, but in this case slackens the cable, moving the mech to the right, towards the smaller sprockets.
 

screenman

Legendary Member
Return Material Authorisation?

Call it what you want Tim, but the first thing you should always start with before adjusting your rear mech is to make sure it is correctly aligned. Having checked I would imagine 30+ bikes I am yet to find one that was properly aligned before I adjusted it.

So from now on RMA = Rear Mech Alignment. Well at least in my little world it will.
 

jonny jeez

Legendary Member
Hi,

I'm about to attempt to index the gears on my bike and am a bit confused.

The instructions in my Haynes manual say to turn the barrel adjuster "away from the bike frame to tighten the gear cable and encourage the derailleur pull the chain up to the bigger sprockets" and "towards the frame to loosen the cable and allow the chain to move down the cassette to higher gears more easily". This seems to make sense according to the 'righty-tighty, lefty-loosey' edict that my dad taught me as a boy...

But then watcthing this video he clearly does the opposite - turning the adjuster in towards the frame to tighten the cable, and away from the frame to loosen it.

So which is correct?! Am guessing it must be the video as it's obviously working for him!
He uses 'clockwise' and 'anti-clockwise' to describe his actions but this kind of adds to the confusion as whether the turn you are making is clockwise or anti obviously alters depending on whether you are behind the mech or in front of it when adjusting it!

So if someone can please confirm whether it's a turn of the adjuster away from the frame or towards the frame to tighten I'd be very grateful. Thanks :-)
I really wouldn't worry too much, just turn the adjuster if the rear mech wont shift up as you do, then try the othr direction. you'll know really fast which is the right direction as the indexing will almost immediately complain and start to rattle then skip.

trim it back and forth until the gear shifts up one, then back it off a little untill andy rattle goes away.

*edit...should say "Any rattle"...sorry Andy, no offence
 
Last edited:

Andy_R

Hard of hearing..I said Herd of Herring..oh FFS..
Location
County Durham
I really wouldn't worry too much, just turn the adjuster if the rear mech wont shift up as you do, then try the othr direction. you'll know really fast which is the right direction as the indexing will almost immediately complain and start to rattle then skip.

trim it back and forth until the gear shifts up one, then back it off a little untill andy_rattle goes away.

Oi!!!:cursing:
 

howard2107

Well-Known Member
Location
Leeds
Select highest gear on the rear mech (smallest sprocket) remove gear cable.
Set lower limit by turning the pedals and pushing the mech towards the wheel onto the lowest gear (biggest cog) adjust the lower limit screw until the chain runs smoothly without either trying to jump into the wheel or trying to move down to next cog.
once this is set, let the mech come down onto the highest gear (smallest cog) and set the high limit screw so that the chain doesnt try to move onto the frame or up to the next cog. In either position the derailleur should be sat directly below the cog, in the case of Shimano some recommend it should be about a half to 1mm to the left, but its about trial and error.

That is high and low limits set.

With the mech in the highest gear (smallest cog) screw the barrel adjuster fully in (clockwise), then reconnect the cable to the mech, pull it finger tight and tighten the screw back up.

To index them, make sure that the chain is running smooth in the highest gear (smallest cog), and whilst running select the next gear up the cassette, the chain will either do nothing, or may try to change to the next gear, in either case screw the barrel adjuster out (anti clockwise until the chain moves into the next gear, and keep turning a bit at a time until it runs smooth in that gear, once you have achieved this it should change up and down without any fuss through the full range of gears, you can fine tune by adjusting the barrel adjuster a bit at a time, and by a bit, i mean an eighth to a quarter of a turn at a time. It can be a bit frustrating to get it right especially at your first attempt, and once it is under load when riding, you may need to make minor tweaks to get it spot on.

However, all of this is a waste of time if any of your cables are worn, the chain is stretched, or there is any damage to the components. So make sure all is well, clean and lubed or you will never get it right.

It is well demonstrated on you tube as others have said.
 
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