Originally Posted by cyccommute (Post 22241055)

Try cable adjustment before you replace the derailer. If the cable adjustment doesn’t work, try tuning the limit screws.

Originally Posted by Awesomeguy (Post 22240972)

I know that front derailleur problems are common, but is it beneficial in this regard if you have higher end components, like deore or shimano 105 etc.??


I have Acera front derailleur and Alivio rear derailleur, rest of the bike is acera.
I know 1X is a trend right now, but i think i like 2X most since you wide range of cadence\gear options.

Originally Posted by restlessswind (Post 22239959)

Fun Fact: 78.327% of statistics are made up.

Originally Posted by Maelochs (Post 22241016)

Acera and Alivio are not great groups .... but they are serviceable. They will do the job. In my experience the lower-end Shimano stuff flexes more, and seems to stay adjusted less, than the good stuff. But ... it all works.

I have an Acera RD on my Cannondale tourer, and a Claris triple FD ..... and I have zero complaints. (Claris is comparable to Acero, just road vs MTB-oriented.) Set them up right, ride them, and if they need a tweak now and then, an 1/8 turn on the barrel adjuster usually does it.

The important thing with derailleurs is having a clue how to set them up. I don't, so I visited Park Tools' website and both printed the text and copied the video links for their instructions. That, plus a couple other YouTube videos, made setting up, adjusting, and indexing seem as simple as it actually is.

I sometimes have a hard time following seemingly complex instructions because I try to remember everything. Some stuff just seems daunting. I just learn step-buy-step, make sure I understand each step, and then after I am sure I know Step One, I move on. Eventually the stuff I thought was super-complicated and difficult, is commonplace and simple.

My advice would be, Don't just go in there turning screws and barrel adjusters randomly, to see what happens. Cable tension and limit screws affect each other---if the cable isn't pulling the derailleur all the way to the limit, then you can turn the screw until it falls out .... and if the derailleur hits the inner (L) screw turning the barrel adjuster won't do a thing---but then, when you finally get the limit screw properly adjusted, the cable will be an issue because you adjusted it for a different range of motion.

And with the rear derailleur, if you have removed the "dork disc" on your rear hub, and if you set the rear Low limit screw too far out, your derailleur will dive into your spokes, often ripping the derailleur off the frame, bending the derailleur hanger, and maybe breaking a couple spokes. Guaranteed highlight of your day.

Go slowly through the instructions. They are Not complicated, taken in small pieces. Think about how complex the instructions for tying and double-knotting shoelaces would be, printed out ..... adjusting your derailleurs and cables is a lot simpler than that.

Originally Posted by cxwrench (Post 22241079)

Maybe he should figure out what the problem actually is before randomly adjusting cable length or 'tuning' the limit screws.

Originally Posted by Awesomeguy (Post 22241112)

I totally try it out right now, my only issue, is i don't have one of those stands to troubleshoot, i might have to order it, since, taking it to the shop each time , can be a bit much .

Originally Posted by Awesomeguy (Post 22241197)

what is considered a group set?

Originally Posted by cyccommute (Post 22240032)

... I’ve even picked up the name “derailer whisper” at my co-op.

Originally Posted by redcon1 (Post 22242406)

As the resident 'whisperer' you may want to research how to spell 'derailleur' correctly. That might help with your street cred. ;)

Originally Posted by cyccommute (Post 22240032)

I’ve even picked up the name “derailer whisper” at my co-op.

Originally Posted by redcon1 (Post 22242406)

As the resident 'whisperer' you may want to research how to spell 'derailleur' correctly. That might help with your street cred. ;)

Originally Posted by tomato coupe (Post 22242802)

When someone calls you a "whisperer" it's a compliment. When someone calls you a "whisper" it's not.

Originally Posted by cyccommute (Post 22242816)

So what have either of you contributed to the conversation? Any suggestions or are you just here to play unfunny versions of Statler and Waldorf? At this point, I’d say ya got nothin’.

Originally Posted by tomato coupe (Post 22242828)

The Statler and the Waldorf are both hotels, aren't they? I've never seen a funny hotel.

Originally Posted by Maelochs (Post 22241474)

Cyccommute is mostly right. If i were in your situation, I would adjust the front cable tension as I suggested above---I wuold actuyally start from scratch, but you probably---Probably---just need to turn the front barrel adjuster and eighth or a quarter turn.

As he suggests, shift into high and yank the cable and see if the derailleur swings further outward. if it does the cable is loose and the limit screw is probably fine--and if the screw also needs adjustment, you can't do it properly without adjusting the cable tension anyway.

I am completely serious here---having been in many situations just like this. Stand the bike up somewhere, shift the front derailleur into high, and yank the cable---see if the derailleur moves. This is the first test I would perform if it were my bike--or if it were yours and you were a friend.

Originally Posted by Awesomeguy (Post 22275422)

im getting the run again lol, so how is cable tension related to high and low limit screws?
If I bring the derailleur outward do I have to slacken the cable first ?

Originally Posted by cyccommute (Post 22275472)

Cable tension really isn’t related to the limit screws. The limit screws only set the travel distance. The low limit screw prevents the derailer from moving too far inboard while knocking the chain off the inner chainwheel. The high limit screw limits how far outboard the derailer can move and prevents the chain from falling off the outside.

The cable, on the other hand, is what moves the derailer between those two limits. If the cable is too slack, the derailer can’t move far enough outboard so that the chain jumps up to the largest cog. If it is too tight, it won’t allow the chain to move to the inner chainwheel. The former…i.e. cable too tight… is by far the most common problem.

Understanding the relationship between the cable tension and how the derailer (front or rear) moves is the key to understanding derailers and keeping them working properly. Far too often people think the limit screws are the key. They are not.

Originally Posted by Awesomeguy (Post 22275822)

so my issue is that the shifts are perfectly fine, it’s just in the bigger ring (2x) up front , and biggest three gears in the back , chain rubs the outer plate. If I just loosen the h screw , to bring derailleur outward , with that work? Also if I listen or tighten the high or low screws does that man I need to adjust barrel adjuster ?

Originally Posted by cyccommute (Post 22275939)

Again, the limit screws only limit how far the derailer moves but not how it moves. Chain rubbing in extreme gears…like the biggest cog on the rear with the large chainring…is somewhat normal. It can be a function of the derailer or the derailer alignment but even then, you are more likely to experience chain rub in those combinations. If you are using Shimano front derailers, the more expensive ones tend to rub more in my experience. Those tend to be narrower than cheaper versions (Tiagra and lower).

Your shifters should also have a “trim” feature which is a soft click (like about a half shift) in the shifter. This will move the front derailer just a little bit in those more extreme gears and reduce rub. I use triples exclusively and the trim is in the middle ring. I don’t recall if it is on the inner ring or outer ring on doubles.

Finally, you don’t need to use the large ring/large(r) cog combinations. Use a gear calculator and see where those gears are duplicated. Shift before you get to the gears that tend to rub.

Originally Posted by Awesomeguy (Post 22275953)

when I say big gear in the back, I man the smallest cog in the back and largest upfront

Originally Posted by cyccommute (Post 22276125)

Okay. Got ya now. Most people talk about the “big gear” in back as the largest cog. You’ve got it the right way around because the smallest cogs are the highest gears. Now that I have it straight and we’re on the same page, we can proceed with looking at solutions. There’s a couple of things to check. First look at the derailer alignment. The picture below shows what your problem could be. “C” is the proper alignment. The outer plate should be parallel with the chainwheels. Either A or B could result in chain rub over multiple gears in the back.

https://lh4.googleusercontent.com/pq...4ArpciV4=s1600

Your issue could still be a cable issue or may also be a cable issue. Both could happen simultaneously. Shift down to the lowest gear in the front and see if your cable is tight. If it is loose, the derailer won’t move out far enough. The cable should be fairly tight.

Another, more complicated, possibility could be the chain line isn’t right. After you’ve checked everything else first, see if you can move the front derailer outboard by hand. You might have to loosen the height limit screw to see if you can move it out any more…again by hand. If you can’t move it out any further and it is still rubbing, you might need to move the drive side inboard. It’s fairly easy with the crank you have. You will just need to move spacers from the drive side to the nondrive side. It’s a little complicated but not too difficult to do. The crank is easy to remove and you just need a tool to remove the bottom bracket cups. Move the driveside spacer to the nondriveside.

You might not need to move all 2.5mm from the drive side depending on how much you need to move the chainline. You can get spacers in different thicknesses to tune the amount you need to move the crank if you don’t need the full 2.5mm.

Try the other fixes…they are easier…first.