rear derailleur set up

[hesdownagain]

hi. trying to build a gt i-drive from frame up, never done this sort of thing so i'm using forum and u-tube how to's. i have a slx rear derailleur i'm trying to set up. all the u-tube how to's show derailleur's with a fine tune adjustment on the rear of the derailleur, mine of course does not have this only the one on the shifter. can anyone point me in the direction of a how to showing the fine tune of the derailleur. got the high/low limit done ok just cant get the smooth change from one cog to the other right. thanks for any help. dave.

 

[FluffyChicken]

You need to twiddle the adjuster on the shifter like you say.

The best way to learn is to pedal and alter the adjuster and see and hear what happens, that way you know what is going on.

Then once you've figured it, go for a ride and do it then.

While riding
Start with shifting down, if it doesn't go down after a click then release some cable (turn the adjusting so it goes in) until it does. Once it drops down add say a 1/4 twist.
Then do it as it goes back up to the larger cog one by one. If your lucky it'll be perfect if not and it will not go up then a drop to the smallest again and add a little turn (barrel adjust out, shouldn't need much ad you've got just over a 1/4 turn to play with really) keep trying till it feels right.

This way you get an idea of what is happening and should be able to hear the problem in future so you can alter on the move if needed.

Shadow rear mechs are also (as I've found out reading Shimano docs) more critical the the jocky height, (i.e. adjusting b-tension screw).
They give quite a specific distance it should be, ... (EDIT found the link now http://bike.shimano.com/publish/content ... le.html/14)%20Shadow%20RD%20Tips.pdf)

I'll add, while I've not used this I came across this page while helping someone else
http://www.exchangecycletours.org/rdadjustment.htm

 

[drcarlos]

How I do it is:

Start with the shifter in the highest gear number (rear) and lowest (front) and with the cable unconnected
1. Turn the adjuster a couple out (unscrew).
2. Then tension the cable using pliers (not too much just one hand and body weight pulling on the cable is enough here) and tighten the bolt on the mech (this goes for front or rear).
3. Shift up one gear, does it shift? Yes, keep going until it fails to shift up one gear, then return the shiter to the previous correctly shifted gear and turn the tensioner out 1/2 a turn and repeat the shift attempt, continue this for the rest of the block until you are in the first cog. The shifter should also indicate 1. If it does not indicate 1 or you haven't reached the top of the block you need to start again as you got initial tension wrong.
4 Downshifting shift down one gear until it fail to shift then slacken the adjuster half a turn then return to the lowest gear and repeat until all down shifts are successful, then check the upshifts using part 3.
5. Ride and check shifts using 3 and 4.

This sounds complex and I have no idea if it is near what mechanics do but works for me and I can have a set of rears working in less than 5 minutes and have since about 14 years old.

For Setting up the rear mech I always use the middle ring or the inner on a twin setup.

Carl.

 

[dyna-ti]

Where are you ?
There must be another member in the area that could come over and show you how to do it.
whilst drinking all your good coffee and snaffling the chocolate biscuits
There is some phrase or other about this :?

 

[hesdownagain]

thank you all for the help. i'm in birmingham a spit away from sutton park. i will have a go at the fix. thanks dave.

 

[cyfa2809]

iput mine upside down and do it that way (sram rear mech only has shifter adjustment)
remember, you want to leave some asjustment at the shifter, so if you are unscrewing it too much to tighten it up, you probably need to un do it again and pull a bit more cable through

when checking, i always shift, one up the down again, 2 up one down etc.
so i check that it shifts between every gear fine

 

[cyfa2809]

mabe you will find this useful

http://www.pinkbike.com/news/tech-tuesday-sram-rear-derailleur-adjustments-2010.html

 

[hesdownagain]

mabe you will find this useful

http://www.pinkbike.com/news/tech-tuesday-sram-rear-derailleur-adjustments-2010.html

thanks for the reply. i have the shimano slx. it has no adjustment on the derailluer it's self. it seems to be one of these things that you think you have it then you go through the gears again and it's wrong. bummer..

 

[hesdownagain]

easy this ain't it. 6 hours now and i can't get it right. may i say not in one go i threw the bike up the garden and went for a pint, that was just after my lady told me to think of the feeling i will have when i get it right. she did'nt say much more after i head butted her. lol. back to it..

 

[FluffyChicken]

Sounds like something is wrong with the setup.
Bad cabling, something sticking, Did you cut the cables yourself ?
Bent this that etc.. poor chain cassette etc...


It really shouldn't be difficult, once aligned and in 6 hours (minus downtime ) you must have gone through the correct place. Hence somethign else must be wrong