Do front derailleurs inherently kinda suck?

[Mike Kozlowski]

A few weeks ago, I bought a bike (Diamondback Topanga Comp '04) for the first time since the '80s.
The most impressive improvement, obviously, is the indexed shifting. It's deeply cool.

But: It seems to work much more smoothly on the rear than on the front. Front gear shifts are
slower, jerkier, and way more likely to "miss" (i.e., not shift, and leave the chain rubbing up
against the side of the shifting mechanism; or shift, and leave the chain rubbing up against
the side).

Why is this? Is it because the front derailleur isn't as good as the rear one (Deore vs. LX)? Is it
because the front derailleur is a bit out of alignment? Or is it just that front shifts are
inherently more awkward than rear ones?

--
Mike Kozlowski http://www.klio.org/mlk/

 

[John Morgan]

> But: It seems to work much more smoothly on the rear than on the front. Is it because the front
> derailleur isn't as good as the rear one (Deore vs. LX)?

Yes.

> Is it because the front derailleur is a bit out of alignment?

Yes.

> Or is it just that front shifts are inherently more awkward than rear ones?

Yes.

-John Morgan
--
"I tried lube, careful prying, careful digging and even not so careful digging. Little chunks of
rubber." --Sad Bob

 

[B. Sanders]

"Mike Kozlowski" <[email protected]> wrote in message news:[email protected]...
> A few weeks ago, I bought a bike (Diamondback Topanga Comp '04) for the first time since the '80s.
> The most impressive improvement, obviously, is the indexed shifting. It's deeply cool.
>
> But: It seems to work much more smoothly on the rear than on the front. Front gear shifts are
> slower, jerkier, and way more likely to "miss" (i.e., not shift, and leave the chain rubbing up
> against the side of the shifting mechanism; or shift, and leave the chain rubbing up against
> the side).

Jerkiness is the hallmark of indexed front derailleurs. If you're not used to it, you probably
wonder what all the clunking is about. Sounds like something must be wrong.

> Why is this? Is it because the front derailleur isn't as good as the rear one (Deore vs. LX)?

Deore front derailleurs are kinda flimsy, IMO; but that's probably not the problem.

> Is it because the front derailleur is a bit out of alignment?

There could be problems with alignment (angular), position (on the seat tube), limit adjustment, or
cable tension adjustment. Cable tension is the most common mis-adjustment, followed by limit screw
settings (two screws that are used to adjust the inner and outer limits of travel for the front
derailleur).

> Or is it just that front shifts are inherently more awkward than rear
ones?

Well, that's also part of it. It's often much harder to get front derailleurs "dialed in" than rear
derailleurs. Many riders prefer shifters that allow the front derailleur to be "trimmed" (adjusted)
while riding, instead of the 3-position indexed shifting that most shifters have nowadays.

-=B=-

 

[T_blood]

"Mike Kozlowski" <[email protected]> wrote in message news:[email protected]...
> A few weeks ago, I bought a bike (Diamondback Topanga Comp '04) for the first time since the '80s.
> The most impressive improvement, obviously, is the indexed shifting. It's deeply cool.
>
> But: It seems to work much more smoothly on the rear than on the front. Front gear shifts are
> slower, jerkier, and way more likely to "miss" (i.e., not shift, and leave the chain rubbing up
> against the side of the shifting mechanism; or shift, and leave the chain rubbing up against
> the side).
>
> Why is this? Is it because the front derailleur isn't as good as the rear one (Deore vs. LX)? Is
> it because the front derailleur is a bit out of alignment? Or is it just that front shifts are
> inherently more awkward than rear ones?

Here is my take on the front vs. rear derailer dilemma. First look at the difference in clearance
between front and rear cogs. The rear makes only a little jump and the front a much bigger jump.
Also, rear cassettes are generally grooved and the "catching tooth" is angled to accept the shift,
providing a smoother almost unnoticeable shift. Then look at the engineering feat of your rear
derailer and then look at the piece of metal consisting of your front derailer. In my opinion much
more concentration and design was put forth in designing rear derailers. They are where the bread
and butter
is. I rarely shift my front, but the rear is in constant motion.

 

[T_blood]

"> Here is my take on the front vs. rear derailer dilemma. First look at the
> difference in clearance between front and rear cogs. The rear makes only a little jump and the
> front a much bigger jump. Also, rear cassettes are generally grooved and the "catching tooth" is
> angled to accept the shift, providing a smoother almost unnoticeable shift. Then look at the
engineering
> feat of your rear derailer and then look at the piece of metal consisting
of
> your front derailer. In my opinion much more concentration and design was put forth in designing
> rear derailers. They are where the bread and butter
> is. I rarely shift my front, but the rear is in constant motion.

Or be like JD and say funk all that technical ********!

 

[Van Bagnol]

In article <AB0ab.55389$cj1.13139@fed1read06>,
"John Morgan" <[email protected]> wrote:

> > But: It seems to work much more smoothly on the rear than on the front. Is it because the front
> > derailleur isn't as good as the rear one (Deore vs. LX)?
>
> Yes.

Shifting the rear is far more frequent (and thus subject to wear) than the front, so the rear
derailleur is typically of higher grade componentry.

> > Is it because the front derailleur is a bit out of alignment?
>
> Yes.

Front shifts are jerkier than rear, but shifting shouldn't miss or cause prolongued chain rub. It
seems that your front mechanism needs adjusting.

> > Or is it just that front shifts are inherently more awkward than rear ones?
>
> Yes.

The front has the task of making 10- to 12-tooth gear changes to a chain loaded with up to 800
pounds of tension. The rear has to make 1- to 3-tooth changes on the slack part of the chain. What
do you think?

Van

--
Van Bagnol / v a n at wco dot com / c r l at bagnol dot com ...enjoys - Theatre / Windsurfing /
Skydiving / Mountain Biking ...feels - "Parang lumalakad ako sa loob ng paniginip" ...thinks - "An
Error is Not a Mistake ... Unless You Refuse to Correct It"

 

[Alex Bird]

Mike Kozlowski <[email protected]> wrote in message news:<[email protected]>...
> Or is it just that front shifts are inherently more awkward than rear ones?

Yes. The rear derailleur 'de-rails' the returning chain, which is only under the tension provided
by the derailleur spring. The front de-rails the top of the chain, the part you are pulling at high
tension, AFAIK no front derailleurs are designed for shifting at full steam, and will work much
better if you relax your pedalling until they're 'in'. The larger difference between the
chainwheels is another factor, and using a set of parts designed to go together is probably a
shortcut to derailleur joy, but as I never have it's just another of those pipe dreams ;0) It's one
of those things which may need adjustment as the bike 'settles', and is valuable knowledge anyway,
get stuck in.

Alex

 

[Bill Wheeler]

On Wed, 17 Sep 2003 17:05:36 +0000 (UTC), Mike Kozlowski <[email protected]> wrote:

>A few weeks ago, I bought a bike (Diamondback Topanga Comp '04) for the first time since the '80s.
>The most impressive improvement, obviously, is the indexed shifting. It's deeply cool.
>
>But: It seems to work much more smoothly on the rear than on the front. Front gear shifts are
>slower, jerkier, and way more likely to "miss" (i.e., not shift, and leave the chain rubbing up
>against the side of the shifting mechanism; or shift, and leave the chain rubbing up against
>the side).
>
>Why is this?

Nature of the beast. Read, Adjust, Ride...repeat until problem solved. Or simply get rid of the
damn thing.

Peace, Bill

 

[Fredzep]

"Mike Kozlowski" <[email protected]> wrote in message news:[email protected]...
> A few weeks ago, I bought a bike (Diamondback > front. Front gear shifts
are slower, jerkier, and way more likely to
> "miss" (i.e., not shift, and leave the chain rubbing up against the side of the shifting
> mechanism; or shift, and leave the chain rubbing up against the side).

I would bring it back to the shop and tell them. More than likely its just out of adjustment
although the front can be a bit more toublesome to get dialed in just right IMO.

Fredzep
--
"Gravity is a harsh misstress" The Tick

 

[Greg P.]

"Mike Kozlowski" <[email protected]> wrote in message news:[email protected]...
| Why is this? Is it because the front derailleur isn't as good as the rear one (Deore vs. LX)? Is
| it because the front derailleur is a bit out of alignment? Or is it just that front shifts are
| inherently more awkward than rear ones?

I am a huge bike rider (all styles), but I am a novice (reading as much as I can) when it comes to
the technical, repair part of bikes. I've had the same problem you have on two mid-high priced
Specialized bikes. I had the dealer adjust the front der about 8 times until I realized that it was
actually just the way it behaves. Quality and manufacturer are indeed points to consider, but the
front der was not meant (IMO) to be used that often, thus the lack of consideration when designing
them. If you have 8+ speeds in the back, I suggest to just stay in your middle ring (in the front)
and go about them solely.

 

[Jd]

Mike Kozlowski <[email protected]> wrote in message news:<[email protected]>...
> A few weeks ago, I bought a bike (Diamondback Topanga Comp '04) for the first time since the '80s.
> The most impressive improvement, obviously, is the indexed shifting. It's deeply cool.
>
> But: It seems to work much more smoothly on the rear than on the front. Front gear shifts are
> slower, jerkier, and way more likely to "miss" (i.e., not shift, and leave the chain rubbing up
> against the side of the shifting mechanism; or shift, and leave the chain rubbing up against
> the side).
>
> Why is this? Is it because the front derailleur isn't as good as the rear one (Deore vs. LX)? Is
> it because the front derailleur is a bit out of alignment? Or is it just that front shifts are
> inherently more awkward than rear ones?

It's because you didn't buy a singlespeed.

Take it ack to the bike shop and have them adjust it properly if you think it needs it. If someone
here tries to tell an obvious novice such as yourself how to adjust it, they are an idiot and you
shouldn't listen to them.

JD

 

[Mike Kozlowski]

In article <[email protected]>, Van Bagnol
<[email protected]> wrote:

>Front shifts are jerkier than rear, but shifting shouldn't miss or cause prolongued chain rub. It
>seems that your front mechanism needs adjusting.

Well, if I undo the shift, and then redo it, it's usually fine, which makes me think that I'm just
shifting too tentatively or something. (I don't know if that's even possible; indexed shifting still
strikes me as magical.)

The only time there's prolonged chain rub is if I have both the front and the rear in the outermost
gears... so I just don't do that.

>The front has the task of making 10- to 12-tooth gear changes to a chain loaded with up to 800
>pounds of tension. The rear has to make 1- to 3-tooth changes on the slack part of the chain. What
>do you think?

Makes sense.

Good to know; thanks.

--
Mike Kozlowski http://www.klio.org/mlk/

 

[Tom Walker]

[email protected] (JD) wrote in message news:<[email protected]>...
> Mike Kozlowski <[email protected]> wrote in message news:<[email protected]>...
> > A few weeks ago, I bought a bike (Diamondback Topanga Comp '04) for the first time since the
> > '80s. The most impressive improvement, obviously, is the indexed shifting. It's deeply cool.
> >
> > But: It seems to work much more smoothly on the rear than on the front. Front gear shifts are
> > slower, jerkier, and way more likely to "miss" (i.e., not shift, and leave the chain rubbing up
> > against the side of the shifting mechanism; or shift, and leave the chain rubbing up against the
> > side).
> >
> > Why is this? Is it because the front derailleur isn't as good as the rear one (Deore vs. LX)? Is
> > it because the front derailleur is a bit out of alignment? Or is it just that front shifts are
> > inherently more awkward than rear ones?
>
> It's because you didn't buy a singlespeed.
>
> Take it ack to the bike shop and have them adjust it properly if you think it needs it. If someone
> here tries to tell an obvious novice such as yourself how to adjust it, they are an idiot and you
> shouldn't listen to them.
>
> JD

Agreed. IME, dialing in the front derailleur is the trickest mechanical thing you'll do on your
bike. See if you can get your mechanic to show you what he's doing when he adjusts it again if you
want to learn. Trying on your own will guarantee at least one lost afternoon and STILL probably
won't shift right.

A well set up derailleur, even a cheap Deore or LX, will shift smoothly an properly if its set up
well. The problem is, it takes a lot of effort to set it up well so a lot of shops don't take the
time to make it bullet proof when assembling the bikes.

T

 

[Bill Wheeler]

On 19 Sep 2003 05:53:09 -0700, [email protected] (Tom Walker) wrote:

[snip]
>> Take it ack to the bike shop and have them adjust it properly if you think it needs it. If
>> someone here tries to tell an obvious novice such as yourself how to adjust it, they are an idiot
>> and you shouldn't listen to them.
>>
>> JD

Not only should you listen to me you should trust me with your life. Only an idiot wouldn't.

WTF is "ack"?!

>
>Agreed. IME, dialing in the front derailleur is the trickest mechanical thing you'll do on your
>bike. See if you can get your mechanic to show you what he's doing when he adjusts it again if you
>want to learn. Trying on your own will guarantee at least one lost afternoon and STILL probably
>won't shift right.

Begging the Colonel's pardon....but that's Bvllshit! If you can read at an eighth grade level,
know how to measure, use a phillips or a flat head screwdriver, then you're in good shape. 10
minutes tops.

Of course in my not so friggin humble OPINION you should get rid of the damn thing a start riding a
real bike, SS.

 

[Chris]

"Bill Wheeler" <[email protected]> wrote in message
news:[email protected]...
> On 19 Sep 2003 05:53:09 -0700, [email protected] (Tom Walker) wrote:
>
> [snip]
> >> Take it ack to the bike shop and have them adjust it properly if you think it needs it. If
> >> someone here tries to tell an obvious novice such as yourself how to adjust it, they are an
> >> idiot and you shouldn't listen to them.
> >>
> >> JD
>
> Not only should you listen to me you should trust me with your life. Only an idiot wouldn't.
>
> WTF is "ack"?!
>
> >
> >Agreed. IME, dialing in the front derailleur is the trickest mechanical thing you'll do on your
> >bike. See if you can get your mechanic to show you what he's doing when he adjusts it again if
> >you want to learn. Trying on your own will guarantee at least one lost afternoon and STILL
> >probably won't shift right.
>
> Begging the Colonel's pardon....but that's Bvllshit! If you can read at an eighth grade level,
> know how to measure, use a phillips or a flat head screwdriver, then you're in good shape. 10
> minutes tops.
>
> Of course in my not so friggin humble OPINION you should get rid of the damn thing a start riding
> a real bike, SS.

We all know SS isn't for everyone. And, finagling a front derailleur can either take two seconds or
two days. Once I slapped on an XTR (replacing an
LX) and spent an hour tweaking it, my front shifting problems were solved...even though I maintain
the idea that XTR is, by and large, a ripoff if you - and not a sponsor - are paying for it, and
I am able to get dependable shifting out of the LX. Go XT for the best performance-for-price
relationship.

Anyway, since there are so many variables in a front der setup - cage angle relative to chainrings,
mounting height, cable tension, limit screw adjustment - it is nearly impossible to get it right if
you're new to wrenching. Once you do, however, you feel good and the bike works well. Which makes
you feel even better. So, I recommend the OP gets a simple bit of instruction as to how the front
mech works, then spends some (a bunch) time fiddling with it. The payoff is huge.

But, relative to rear shifting, the front derailleur just doesn't work as well as the rear...for all
the reasons everyone else mentioned...chainring tooth difference, etc. Still, don't be afraid to
tweak it. A good LBS can always bail you out if you screw the pooch beyond all repair.

Chris

 

[Tom Walker]

"Bill Wheeler" <[email protected]> wrote in message
news:[email protected]...
> On 19 Sep 2003 05:53:09 -0700, [email protected] (Tom Walker) wrote:
> >Agreed. IME, dialing in the front derailleur is the trickest mechanical thing you'll do on your
> >bike. See if you can get your mechanic to show you what he's doing when he adjusts it again if
> >you want to learn. Trying on your own will guarantee at least one lost afternoon and STILL
> >probably won't shift right.
>
> Begging the Colonel's pardon....but that's Bvllshit! If you can read at an eighth grade level,
> know how to measure, use a phillips or a flat head screwdriver, then you're in good shape. 10
> minutes tops.
>
> Of course in my not so friggin humble OPINION you should get rid of the damn thing a start riding
> a real bike, SS.

Great, by this logic, someone who's never touched a tool before can buy a Chilton's manual and
completely strip and rebuild a car in a Saturday afternoon.

For a newbie, adjusting a front derailleur is very tricky and will take way longer than 10 minutes
to dial in perfectly. Ten minutes is what it takes for the 15 year old kid who built the bike to get
it shifting on the stand.

T

 

[Jd]

Bill Wheeler <[email protected]> wrote in message
news:<[email protected]>...
> On 19 Sep 2003 05:53:09 -0700, [email protected] (Tom Walker) wrote:
>
> [snip]
> >> Take it ack to the bike shop and have them adjust it properly if you think it needs it. If
> >> someone here tries to tell an obvious novice such as yourself how to adjust it, they are an
> >> idiot and you shouldn't listen to them.
> >>
> >> JD
>
> Not only should you listen to me you should trust me with your life. Only an idiot wouldn't.
>
> WTF is "ack"?!

It's what Bill The Cat says.

> >Agreed. IME, dialing in the front derailleur is the trickest mechanical thing you'll do on your
> >bike. See if you can get your mechanic to show you what he's doing when he adjusts it again if
> >you want to learn. Trying on your own will guarantee at least one lost afternoon and STILL
> >probably won't shift right.
>
> Begging the Colonel's pardon....but that's Bvllshit! If you can read at an eighth grade level,
> know how to measure, use a phillips or a flat head screwdriver, then you're in good shape. 10
> minutes tops.

We're talking about a novice here, Bill. Mechanical inclination and retardation have a really wide
spectrum as well.

JD

 

[The Ogre]

Bill Wheeler <[email protected]> wrote in message
news:<[email protected]>...
> On 19 Sep 2003 05:53:09 -0700, [email protected] (Tom Walker) wrote:
>
> [snip]
> >> Take it ack to the bike shop and have them adjust it properly if you think it needs it. If
> >> someone here tries to tell an obvious novice such as yourself how to adjust it, they are an
> >> idiot and you shouldn't listen to them.
> >>
> >> JD
>
> Not only should you listen to me you should trust me with your life. Only an idiot wouldn't.
>
> WTF is "ack"?!
>
> >
> >Agreed. IME, dialing in the front derailleur is the trickest mechanical thing you'll do on your
> >bike. See if you can get your mechanic to show you what he's doing when he adjusts it again if
> >you want to learn. Trying on your own will guarantee at least one lost afternoon and STILL
> >probably won't shift right.
>
> Begging the Colonel's pardon....but that's Bvllshit! If you can read at an eighth grade level,
> know how to measure, use a phillips or a flat head screwdriver, then you're in good shape. 10
> minutes tops.
>
> Of course in my not so friggin humble OPINION you should get rid of the damn thing a start riding
> a real bike, SS.

If you ride on trails where they allow free range acks you have to dodge bvllshit.

That said, I think it all depends on how mechanical you are. If you fix your neighbors lawn mover
every spring time for kicks you will probably have no problem with getting the front mech perfect in
a couple of hours (maybe less). But there are tons of us who are not good with gadgets.

The first time I messed with mine I fscked it up much worse than it was when I started (Brother
fixed it). The second time I wound up taking it into the shop to have them fix it. Eventually I got
it right but it took me some time. (You can poke fun at me now) Some people just don't grok
mechanical stuff quickly. On a brighter note, once I do finally get it I generally do fairly well
and only break things occasionally.

I guess what I am saying is that it depends on the person.

-- The Ogre

So

 

[Bill Wheeler]

On Sat, 20 Sep 2003 06:23:55 GMT, "Chris" <[email protected]> wrote:

[snip
>We all know SS isn't for everyone. And, finagling a front derailleur can either take two seconds or
>two days. Once I slapped on an XTR (replacing an
>LX) and spent an hour tweaking it, my front shifting problems were solved...even though I maintain
> the idea that XTR is, by and large, a ripoff if you - and not a sponsor - are paying for it,
> and I am able to get dependable shifting out of the LX. Go XT for the best
> performance-for-price relationship.
>
>Anyway, since there are so many variables in a front der setup - cage angle relative to chainrings,
>mounting height, cable tension, limit screw adjustment - it is nearly impossible to get it right if
>you're new to wrenching. Once you do, however, you feel good and the bike works well. Which makes
>you feel even better. So, I recommend the OP gets a simple bit of instruction as to how the front
>mech works, then spends some (a bunch) time fiddling with it. The payoff is huge.
>
>But, relative to rear shifting, the front derailleur just doesn't work as well as the rear...for
>all the reasons everyone else mentioned...chainring tooth difference, etc. Still, don't be afraid
>to tweak it. A good LBS can always bail you out if you screw the pooch beyond all repair.
>
>Chris
>

Okay, I agree there are certain things that can be a bit tricky.

 

[Bill Wheeler]

On Sat, 20 Sep 2003 15:46:53 GMT, "Tom Walker" <[email protected]> wrote:

[snip]
>Great, by this logic,

I'm impressed you agree my logic is great.

>someone who's never touched a tool before can buy a Chilton's manual and completely strip and
>rebuild a car in a Saturday afternoon.

Front Derailleurs, Front Derailleurs......

>
>For a newbie, adjusting a front derailleur is very tricky and will take way longer than 10 minutes
>to dial in perfectly. Ten minutes is what it takes for the 15 year old kid who built the bike to
>get it shifting on the stand.
>
>T
>
Point taken under consideration.

Peace, Bill