Is my derailleur shot? Thoughts on an overhaul

[icepick_trotsky]

Help me fix my slow shifting.

I'm using a 10 speed Daytona RD, circa 2001 or so with matching ergos. It shifts ok, but slowly, especially when shifting into a higher (smaller) cog, and especially in the smallest 3 or 4 cogs on the cassette. It seems like maybe the problem is the spring itself -- it just doesn't move to the right very quickly. I think I can rule out issues with the cables/chain/cassette, as all are new.

What would cause this sluggish shifting, and what should I do about it? Disassemble and overhaul the RD? Do I need to actually replace the spring? Or am I better off just replacing the RD entirely? I've never disassembled a derailleur, so I'm not sure how serviceable these things are.

[dave thompson]

I've never had a rear derailleur 'go bad'. I'd say check/replace all your cabling first.

[AngryScientist]

i absolutely have had a RD go soft after a lot of use. never actually replaced a spring myself, but can say i had the same symptoms, and when i replaced the RD entirely with a new unit, the shifting was magically wayy, wayy snappier. i bet you could replace just the spring if the rest of the RD is in good shape. how do the jockey wheels look?

[icepick_trotsky]

i absolutely have had a RD go soft after a lot of use. never actually replaced a spring myself, but can say i had the same symptoms, and when i replaced the RD entirely with a new unit, the shifting was magically wayy, wayy snappier. i bet you could replace just the spring if the rest of the RD is in good shape. how do the jockey wheels look?

Both wheels look good. I don't think the problem is the shifters, either, they click pretty smoothly when uninstalled.

Any idea where to source the spring?

[oliver1850]

Springs can go south, but I'd try redoing the cable and casing first.

[Formulasaab]

Think about how you tune your rear derailleur and you'll realize the problem with your concern...

Springs, all springs, can lose tension and get weaker over use and time. That is true. However, when you tune your rear derailleur you do it by adjusting the cable tension (and stops). So, when you adjust the tension you make up for any loss that has occurred over time and use. So that's not your problem.

What you are fighting is additional friction somewhere in the system. The spring isn't as strong near the small-cog end of its travel, as it isn't as wound up. That's why it is having more difficulty overcoming the friction there than elsewhere.

You may need to look at the pivots to make sure everything is still tight and smooth. Check to make sure you don't have friction in the shifter body, ferrules, housings, etc. Its in there somewhere.

[jzisk]

If it drops down a cog easily, especially at the smallest ones, the problem is probably not cables, nor springs! You are at the weakest force of the springs when at the smallest cogs... Is the body loose? The alignment bad?

[oldpotatoe]

Help me fix my slow shifting.

I'm using a 10 speed Daytona RD, circa 2001 or so with matching ergos. It shifts ok, but slowly, especially well shifting into a higher (smaller) cog, and especially in the smallest 3 or 4 cogs on the cassette. It seems like maybe the problem is the spring itself -- it just doesn't move to the right very quickly. I think I can rule out issues with the cables/chain/cassette, as all are new.

What would cause this sluggish shifting, and what should I do about it? Disassemble and overhaul the RD? Do I need to actually replace the spring? Or am I better off just replacing the RD entirely. I've never disassembled a derailleur, so I'm not sure how serviceable these things are.

Check cables, housing, BB guide and Der hanger alignment. Detach cable and while pedaling, push Der up cogset and let go..see if it moves down easily and well.

If it doesn't you can find a newer spring but I'm guessing the Der pivots are sloppy or the lever needs an overhaul... Busted post on spring carrier, split spring carrier or tired springs. If the shifter feels clicky, could be a busted post. Not hard to fix.

I'd make sure the cables move in the housing very smoothly, the Der isn't sloppy and moves up and down freely and check the RH lever guts.

[oliver1850]

I interpreted this:

"It shifts ok, but slowly, especially well shifting into a higher (smaller) cog, and especially in the smallest 3 or 4 cogs on the cassette."

as:

"It shifts ok, but slowly, especially WHEN shifting into a higher (smaller) cog, and especially in the smallest 3 or 4 cogs on the cassette."

[icepick_trotsky]

I interpreted this:

"It shifts ok, but slowly, especially well shifting into a higher (smaller) cog, and especially in the smallest 3 or 4 cogs on the cassette."

as:

"It shifts ok, but slowly, especially WHEN shifting into a higher (smaller) cog, and especially in the smallest 3 or 4 cogs on the cassette."

You are correct, typo on my part. Fixed.

[Ralph]

In addition to all the above suggestions.....if the chain is border line long, try taking a couple links out. Has effect of a tighter spring.

[msl819]

I had a similar problem and the culprit was the housing on the rear derailleur was cut too short. If the bend in that cable is too tight it will cause too much friction and the shifting will be as you described. I am sure someone on here can tell you exactly how long that piece needs to be but too short is bad.

[druptight]

Is the cassette worn out and/or roughly the same age as the chain?

[Dead Man]

In every case that I've had slugging spring-return, whether going to small cog or small ring up front, the solution has always been cleaning routing or replacing housing. I've been down the road of thinking my der's return spring were worn out... but it's never been the case. Those things just don't ever seem to wear out.

And yours sounds like pretty textbook friction... so I'd definitely start there.

[rustychisel]

in every case that i've had slugging spring-return, whether going to small cog or small ring up front, the solution has always been cleaning routing or replacing housing. I've been down the road of thinking my der's return spring were worn out... But it's never been the case. Those things just don't ever seem to wear out.

And yours sounds like pretty textbook friction... So i'd definitely start there.

+ 1

[SpokeValley]

I've always wanted to avoid putting any more tension on my der springs than necessary. So, I shift to the lowest neutral position as I come in for a landing after a ride, small ring/small cog, releasing most of the cable tension.

Is this just being anal, or does it have some validity?

[rustychisel]

I've always wanted to avoid putting any more tension on my der springs than necessary. So, I shift to the lowest neutral position as I come in for a landing after a ride, small ring/small cog, releasing most of the cable tension.

Is this just being anal, or does it have some validity?

Called the detente position because the springs are under least tension. It's a rainy day topic unless you ride SRAM of course, in which case it's bound to fail anyway.

[oldpotatoe]

I've always wanted to avoid putting any more tension on my der springs than necessary. So, I shift to the lowest neutral position as I come in for a landing after a ride, small ring/small cog, releasing most of the cable tension.

Is this just being anal, or does it have some validity?

Big boys(pros) do this as well. May be an 'old italian wrenches tale', but I think a good idea and the starting point(small-small) for any drivetrain work after you put it in the stand.

[Russian bear]

How is the derailleur hanger alignment?

[bjf]

How about gunk in the derailleur itself? I had this problem with a DA RD on an ebay bike, and a trip to the ultrasonic cleaner fixed it right up.

[bikinchris]

Undo the rear cable and move the derailleur body by hand to see if it drops to the last cog quickly.
Sometimes, you can raise the tension on the body spring to help shifting to higher gears. Look under the body to see if there is a two position cam to change the tension.
Years ago, there used to be a worm made for Shimano derailleurs. The body spring was super weak to try to make the Grip Shifters work poorly. They spring was so weak they didn't work for long with rapid fire shifters. Someone made a device with an anchor on one end and a set screw to pull the cable back with surgical tubing to increase tension.

[Louis]

I've always wanted to avoid putting any more tension on my der springs than necessary. So, I shift to the lowest neutral position as I come in for a landing after a ride, small ring/small cog, releasing most of the cable tension.

Is this just being anal, or does it have some validity?

My materials class was a long time ago, but as I recall, creep really isn't an issue at room temperatures for any of the types of metals we use structurally on bikes. Plus, if the folks who designed and analyzed the spring in the derailleurs did their jobs properly, we should be operating in in the range where we can safely put a huge number of cycles of min-max-min deflection on the springs without any significant yielding. I wouldn't worry about it, unless doing it makes you feel better.

(and, if you don't do that you can avoid all those unnecessary extra shifts you're adding by shifting to reduce the "resting" tension, are causing you to wear out your system a bit more than you have to ;) )