What does an upgraded derailer do?

[Thurnau]

What does an upgraded derailer do? When I bought my bike the sales guy gently pushed a higher model on me, and one of the things he said was a better derailer among many other things. I know that the derailer changes gears now, but not then. So what exactly does a better one do? Change gears more smoothly? Last longer? Weigh less?

[deraltekluge]

So what exactly does a better one do? Change gears more smoothly? Last longer? Weigh less?One or more of those, depending on what you have and what you change to. It's usually pointless to worry about the weight, though, unless you're an elite racer.

[Mr. Beanz]

Also depends on how much of the group you upgrade. If you upgrade just the rear derailleur, lets say from 105 to Ultegra, might not notice a difference at all. If it's the entire group, shifters,chain, cassette and both der's, might shift a bit better.

Plus the entire group could make a bike lighter, but we're clydes!:D

Another reason some upgrade is for looks. DA has a nice polish where as 105 might be flat grey. The Cool factor!:p

[Thurnau]

Well the front derailer has a tough time going from the middle gear to the larger one. It tales a lot of slipping. The index goes from #2 to #3, but I have to mash it in again for it to actually swap gears. If I adjust the tension on the line it has a tough time from 2 to 1. My LBS said it is a feature of the bike as if it were a safety feature, but it seems more like a trip hazard if you adjusted the gear and then stood up to pedal. This problem is very annoying to me. I did take it back to the LBS once to get looked at, and they said it was calibrated right.

[Thurnau]

I have an entry level MTB trek 3700, and it annoys me so bad I want to give away the bike!:crash:

[Bill Kapaun]

Give it to me!!!
Apparently, you have the C-050 FDER, which is the Tourney or Shimano's entry level shifter.
An upgrade to a Deore level shifter may help, but maybe adjusting your technique might help more?

Do you keep pedaling, but ease off the "force" when you shift to the bigger ring? You pretty much have to do that with all FDER's!

[sstorkel]

Well the front derailer has a tough time going from the middle gear to the larger one. It tales a lot of slipping. The index goes from #2 to #3, but I have to mash it in again for it to actually swap gears. If I adjust the tension on the line it has a tough time from 2 to 1. My LBS said it is a feature of the bike as if it were a safety feature, but it seems more like a trip hazard if you adjusted the gear and then stood up to pedal. This problem is very annoying to me. I did take it back to the LBS once to get looked at, and they said it was calibrated right.

In order to shift properly, you need two things: 1) correct technique, and 2) a properly adjusted derailleur.

Correct technique: continue pedaling while you move the shift lever to the next higher (or lower) gear. If you have STI shift levers, be sure to hold the lever in place until the shift is complete. As others have mentioned, if you're mashing down on the pedals with full force, the derailleur will have a difficult time shifting.

Proper adjustment: make sure that the high-limit screw, low-limit screw, and the cable tension are adjusted properly. The limit screws control how far the derailleur can move from left to right. The cable tension controls how much the derailleur moves from gear to gear. The Shimano website generally has documentation for all of their products.

FWIW, a brand-new bike shouldn't have any problems with shifting!

[v1k1ng1001]

take them both on long rides, see if you can tell the difference

[bautieri]

The index goes from #2 to #3, but I have to mash it in again for it to actually swap gears. If I adjust the tension on the line it has a tough time from 2 to 1. My LBS said it is a feature of the bike as if it were a safety feature

Safety feature, WTF?

If it's possible I would take the bike to a new LBS, I rode a similarly specd mountain bike with the same front der as yours and it never missed a shift. It's not a safety feature, its an incompetent or lazy salesperson at the LBS. Either ask to speak with someone else about it or take it to another shop altogether, the competition would be happy to take your business should your present bike shop be unable to help you.

Hang in there, your bike needs an adjustment and will be fine before long. If the component itself is defective and needs replaced it should be covered under warranty provided your bike was a fairly recent purchase. If you do decided to give the 3700 the ole heave ho let me know, I'll be happy to dumpster dive that critter :)

[Wogsterca]

What does an upgraded derailer do? When I bought my bike the sales guy gently pushed a higher model on me, and one of the things he said was a better derailer among many other things. I know that the derailer changes gears now, but not then. So what exactly does a better one do? Change gears more smoothly? Last longer? Weigh less?

There really isn't much functional difference between the cheapest and most expensive dérailleur (it's actually a French word so to spell it properly it needs the accent), given everything else is the same. Some manufacturers do weird combinations though, so you find everything but the rear dérailleur (RD) is Ultegra, but the RD is 105, in that case switching to an Ultegra RD might make things a little smoother. Sometimes the upgrade will last a little longer as it's built a little better, mostly it's brand recognition and weight though,,,,

[Thurnau]

The main problem is largest ring by the pedal, and the smallest cog(?) by the rear wheel. http://www.parktool.com/repair/readhowto.asp?id=75 has some info to either change the H screw some, or accept it as a limitation. I will work on my shifting technique too:)

[Thurnau]

I was pedaling hard, but I usually go very fast before I adjust to the third gear. Is it bad to jump the front gear around while leaving it on the smallest cog #7?

[Bill Kapaun]

For a 3x7 I'd recommend-
L- 1-5
M- 2-6
H- 3-7
Otherwise, you're cross chaining. That causes-
Noise
Extra wear
Poor shifting

We all do it sometimes, because sometimes it's more prudent to do, than attempt a double shift. Like when a car is bearing down on you etc. Just try to avoid it as a normal course of action.