All these years riding a bike and I still have no idea how to adjust the damn derailleur. 9 times out of 10 I make it worse, the other time I figure out how to get it back to where it was (aka still needs adjustment). So I’m looking for good links that explain the uber complicated adjustment process - the clickety clack is driving me crazy.
youtube is your friend.
All these years riding a bike and I still have no idea how to adjust the damn derailleur. 9 times out of 10 I make it worse, the other time I figure out how to get it back to where it was (aka still needs adjustment). So I’m looking for good links that explain the uber complicated adjustment process - the clickety clack is driving me crazy.
Joel,
The process is made much easier if you have a good bike stand so you can spin the cranks/wheel as you work. Once I finally purchased a good stand it made me realize I should have done it 20 years ago.
YMMV,
Hugh
Park Tool is your friend.
if the derailleur is skipping to a bigger cog, turn the barrel adjuster to the right (move the der right), if it is skipping to a smaller cog turn the barrel the the left (move the der left).
1/2 turn at a time usually does the trick
If you do this and run out of room to adjust it, you need to start fresh.
-Drop to smallest cog
-Loosen cable
-Ensure shifter is shifted all the way down
-Verify lower limit is set where you want it (see manufacturer specs, I know SRAM want’s it to the right, not sure on Shimano, Campy I run directly under)
-Screw in barrel adjuster all the way then back it out 1-1/2 to 2 full turns
-Pull slack from cable and tighten, make sure you have it nice and taught
-Check it and see how it goes, if it’s slow to shift to bigger cogs see notes above i.e. left or right turn of barrel adjuster
-Once it’s dialed check upper limit and adjust if necessary
One thing to remember - the screws for the most part on a bike are 1mm pitch. So, the R. Der adjuster will move 1mm per rotation of the screw. When you unscrew the adjuster by 1.5 turns you are moving the potential for the cable pull and thus the jockey wheel 1.5mm up or down the cogset.
I always always adjust the R. Der with no cable attached at all. Once you have your limits set then you attach the cable and allow the shift lever index to set the motion of the cogs. If you have some jump, with the bike in the stand - it is easy to eyeball the chain line and see if you need to go up or down - knowing that it will move 1mm for every roation of the adjuster bolt. Or, in the instance of a quarter turn - .25mm.
While it seems tedious, it is good to know what distances we are playing with here. The reality is the clearance for the 10 speed cogset is about .01mm when properly adjusted - or 1/10th of a turn of the adjuster.
Did not know this…good tip!
One thing to remember - the screws for the most part on a bike are 1mm pitch. So, the R. Der adjuster will move 1mm per rotation of the screw. When you unscrew the adjuster by 1.5 turns you are moving the potential for the cable pull and thus the jockey wheel 1.5mm up or down the cogset.
I back the barrel out because I tend to pull the cable too tight (or have), this gives me a little breathing room if I need to decrease the tension a bit.
How do you set your upper limit screw without a cable? I have tried and don’t feel I can set it accurately while forcing it over by hand and adjusting it at the same time, with a spinning wheel to make sure it’s not hitting any spokes.
I do it by hand - and I TRY to hit the spokes with it. That is why it is a limit screw. I make damn sure that there is no way for my hand to get the R. Der into the spokes, thus I know there is no way for a cable to get the system to move into the spokes, no matter how maladjusted. I just press my thumb against the body and force it in and eye ball it to the top cog, then make certain that I can not force the chain over the top cog - I am not at all concerned with tuning the top - just be sure I can get there and not pass there. I do all of my tuning with the limit screw on the smallest cog.
Oh, when you do the big cogs, make sure you are in the smallest chain ring. That enables you to also be certain that your chain is not too long.
I never realized that the 2 screws have nothing to do with the position except at the inner most and outter most cogs. Once those are set properly it’s all about the barrel adjuster. Do the stops need to be adjusted for cable stretch or only the barrel adjuster?
http://www.parktool.com/blog/repair-help/rear-derailler-adjustments-derailleur
The stops need never have a cable to be stops - they are stops. The end of motion of the system. If you have cable stretch that is 100% the cable binder - not even the adjuster IMO. It takes nothing to get a 5mm allen and properly tension the cable. To me, the barrel is for adjusting the system if you crash or what ever and need a quick roadside fix - until you get home and fix it properly.
I never realized that the 2 screws have nothing to do with the position except at the inner most and outter most cogs. Once those are set properly it’s all about the barrel adjuster. Do the stops need to be adjusted for cable stretch or only the barrel adjuster?
http://www.parktool.com/...justments-derailleur
The 2 limit screws (labelled H and L) are completely independent of the cable. They bottom out on metal tabs on the derailleur body at the limits of derailleur travel. So usually you set the limit screws when the derailleur is installed on the bike, and never touch them again (assuming all your wheels are identical or close to it).
For index shifting to work precisely, the cable length needs to be just right, so that the derailleur will end up in just the right spot relative to the cog. The barrel adjuster serves to set the effective cable length. Only the barrel adjuster needs to be adjusted for cable stretch; never the limit screws.
The third adjustment screw (Shimano calls it the B-limit screw) is usually only critical if you are using a large cog that is close to the largest that the derailleur can handle. In that case, while the chain is on the largest cog, crank the screw in until the top derailleur pulley has adequate clearance from the cog. Usually, if the B-limit screw is not in far enough, the drivetrain will be very noisy in that gear.
One tip I’ve found useful is to torque the cassette locknut to spec (usually printed on the locknut). Plastic cassette spacers are compressible, and if you don’t get the locknut torque right, the cassette spacing may be slightly off, and no cable adjustment will fix the problem.
Hope this helps. Life for bike mechanics was a lot easier before index shifting. Not that I’d go back!
there is a tip to make it easy to remember which way to adjust:
if the chain is having trouble going “up” the casette, turn the barrel adjuster UP to help it
if the chain is having trouble going “down” the casette, turn the adjust “down”
.
With Horiz drop outs the B screw is about worthless…
And as far as noise in the lowest inch gear - I know many people who do that on purpose. Myself included. That way I can HEAR when I am out of gear and do not try to fall back on another shift. I also can hear when I am cross geared from the 25 to the 53, as much as we claim to properly shift there are times in the heat of the moments we forget to shift the way we intend to. Thank god for Campy as I can drop 8 cogs on the rear and down shift the front at the same time…Shimano is click, click, click, click, click, click, CHUNK, click, click…whew…