Front derailleur / mech question

OK. I'm still trying to find a front derailleur to fit my Giant hybrid
24-speed. You remember the old M330 is worn out and no longer in
production, it seems.

The more I look at the range available, the more confused I get!

Having established, with your help, that I need a top (or dual) pull,
top swing for a 31.8mm fitting, I now find myself worrying about the
following:

What is the difference between a "MECH" and a "DERAILLEUR"?
What difference do the chainset teeth numbers make? The larger toothed
wheel thingy attached to my pedals is a bit larger than usual: an extra
2 teeth, I think (44T ?)
What do you get for your extra pennies? I've seen new derailleur /
mechs on offer from about 10 pounds to over 70 pounds. What is worth the
extra dosh?

Thanks for any assistance offered.

My local bike shops are thicker than I am (honest!).

By the way, I've already enrolled in a 5 year post-grad masters course
with Imperial College, reading "the Mystery of Derailleurs / Mechs" , so
I won't need to bug y'all much longer.

Ta

Goat

Goat wrote:

OK. I'm still trying to find a front derailleur to fit my Giant hybrid
24-speed. You remember the old M330 is worn out and no longer in
production, it seems.

The more I look at the range available, the more confused I get!

Having established, with your help, that I need a top (or dual) pull,
top swing for a 31.8mm fitting, I now find myself worrying about the
following:

What is the difference between a "MECH" and a "DERAILLEUR"?

Nothing. Both are short for "derailleur mechanism".

What difference do the chainset teeth numbers make? The larger toothed
wheel thingy attached to my pedals is a bit larger than usual: an extra
2 teeth, I think (44T ?)

That's smaller than many. My road bike has 52/42/30.

The absolute numbers don't matte much when choosing a front mech. What
does matter is whether it's a double or triple chainset (yours is a
triple), and the difference in teeth between the largest and smallest
chainring. This latter measurement is the capacity of the front mech -
some handle more tooth difference than others.

What do you get for your extra pennies? I've seen new derailleur /
mechs on offer from about 10 pounds to over 70 pounds. What is worth the
extra dosh?

Construction quality, weight, smoothness, longevity. All of these are
independent of, but usually correlated to the price of the mech.

My local bike shops are thicker than I am (honest!).

Move somewhere else, then.

--
Mark.

Front mechs and derailleurs are the same thing ! The specifications
regarding number of teeth relate to the ability of the mech to throw the
chain from one ring to another, this is more crucial if you are using
indexed shifting for the mech where you have very limited, if any, fine
adjsutment (trim). Price usually reflects the quality of the component
rather than its function. I would be surprised if a Deore XT one doesn't
meet your requirments, these are not VERY expensive and are generally
pretty good. More exotic (expensive) models will generally work better,
be easier to set up and be lighter though as I say with indexed shifting
the shifter plays a crucial part as do the chainring spacing. It never
used to be this complicated and for those of us without indexed front
shifting, still isn't.



--

Mark Tranchant wrote:

The absolute numbers don't matte much when choosing a front mech. What
does matter is whether it's a double or triple chainset (yours is a
triple), and the difference in teeth between the largest and smallest
chainring. This latter measurement is the capacity of the front mech -
some handle more tooth difference than others.

With the proviso that MTB front mechs are designed to work with smaller
rings - typically up to 44 T - while road mechs are happier with big rings
around the 52 mark. The profile of the cage differs according to the type
of mech, so MTB mechs won't shift well on road chainsets and vice-versa.

--

Dave Larrington - http://www.legslarry.beerdrinkers.co.uk/
================================================== =========
Editor - British Human Power Club Newsletter
http://www.bhpc.org.uk/
================================================== =========

in message , Goat ')
wrote:

OK. I'm still trying to find a front derailleur to fit my Giant hybrid
24-speed. You remember the old M330 is worn out and no longer in
production, it seems.

The more I look at the range available, the more confused I get!

Having established, with your help, that I need a top (or dual) pull,
top swing for a 31.8mm fitting, I now find myself worrying about the
following:

What is the difference between a "MECH" and a "DERAILLEUR"?

None. The system was invented in France, hence 'derailleur'; it was
adopted by the Americans, hence 'mech'.

What difference do the chainset teeth numbers make? The larger toothed
wheel thingy attached to my pedals is a bit larger than usual: an
extra 2 teeth, I think (44T ?)

The curve of the front derailleur cage should be approximately the same
radius as your largest chain ring but this is not really at all
critical. And 44T is not at all big; all the roadies are riding 52
teeth and more, and some of the small wheel recumbents over 100.

What do you get for your extra pennies? I've seen new derailleur /
mechs on offer from about 10 pounds to over 70 pounds. What is worth
the extra dosh?

Weight - lighter costs more; polish - better polished costs more;
engineering - better engineering costs more. Basically the cheap ones
are made of plastic and pressed steel and work perfectly well; the
expensive ones are made of more exotic materials and work a little
better - but may be no more durable and in fact may not last so long.

--
(Simon Brooke) http://www.jasmine.org.uk/~simon/

;; all in all you're just another click in the call
;; -- Minke Bouyed

Goat wrote:

What is the difference between a "MECH" and a "DERAILLEUR"?

"Mech" is British slang for derailleur. Easier to spell, type and say.

What difference do the chainset teeth numbers make?

The curvature of the front mech cage has to suit the ring sizes and cope
with the differences between rings. And of course the larger the ring
(the greater the number of teeth), the higher the gear is.

The larger toothed
wheel thingy attached to my pedals

....Call that the "outer chainring"...

is a bit larger than usual: an
extra 2 teeth, I think (44T ?)
What do you get for your extra pennies?

Slightly higher gears. Front mech should cope if carefully adjusted, with
a bit of luck.

I've seen new derailleur /
mechs on offer from about 10 pounds to over 70 pounds. What is worth
the extra dosh?

Expensive ones tend to be lighter and look prettier. They don't
necessarily cost much more to manufacture, or work better, but having a
widely priced range of products is a way for the manufacturer to grab
money from all sectors of the market. I think of it as a form of
socialism, actually: You pay what you can afford but everyone gets the
same thing! :-)

Very cheapest ones /might/ not work quite so well, and /might/ not last as
long. I say "might" because even bottom of the range Shimano nowadays
seems to work well to me, and I can't see what's not durable about it.

~PB

Goat:
What is the difference between a "MECH" and a "DERAILLEUR"?

The only difference is that calling it a mech rather than a derailleur makes
you sound more like a 'proper' cyclist.

What difference do the chainset teeth numbers make?

Basically, they work in the opposite way to the cogs on the rear wheel - ie
the bigger wheel for going faster, the smaller wheel for going uphill.

The larger toothed
wheel thingy attached to my pedals is a bit larger than usual: an extra
2 teeth, I think (44T ?)

The difference in practical terms is minimal - the 44 gives you a slightly
larger top gear, which means you might go a wee bit faster downhill. It
won't make any difference going uphill.

What do you get for your extra pennies? I've seen new derailleur /
mechs on offer from about 10 pounds to over 70 pounds. What is worth the
extra dosh?

More expensive kit is usually better engineered, might operate more smoothly
(not always true), and is probably made of lighter, more expensive
materials, but how much you spend is entirely up to you and whether you
think you'll really get any benefit from shaving a few grams off the weight
of your derailleur.

I would suggest avoiding the really cheap stuff and go for the bottom end of
the performance range (eg the Shimano Acera front mech is available as
top-pull in the size you want for £12 from Wiggle). Having said that, when
it comes to front mechs, you don't have to spend much more to get something
higher up the range - and Wiggle have 30% or more off some higher end models
so they end up being the same price. Also look at BikeMagic for user
reviews.

d.

Simon Brooke wrote:

What is the difference between a "MECH" and a "DERAILLEUR"?

None. The system was invented in France, hence 'derailleur'; it was
adopted by the Americans, hence 'mech'.

Most "normal" American cyclists wouldn't know what you meant by a "mech"
even you shoved one up their inner ring. "Mech" is a good old *British*
term.

~PB

davek wrote:

Goat:
What is the difference between a "MECH" and a "DERAILLEUR"?

The only difference is that calling it a mech rather than a derailleur makes
you sound more like a 'proper' cyclist.

As does appending "set" to every bit.

I oiled the springs on my saddleset today, and it's stopped squeaking,
which is a blessed relief. Now the only thing that's making a noise is
my barset, which needs a dab of grease in the stemset clampset.

--
Keith Willoughby
Welcome to the police state - http://tinyurl.com/3cptb

Keith Willoughby wrote:

davek wrote:

Goat:
What is the difference between a "MECH" and a "DERAILLEUR"?

The only difference is that calling it a mech rather than a derailleur makes
you sound more like a 'proper' cyclist.

As does appending "set" to every bit.

I oiled the springs on my saddleset today, and it's stopped squeaking,
which is a blessed relief. Now the only thing that's making a noise is
my barset, which needs a dab of grease in the stemset clampset.

Some exaggeration, surely. The set is more than a single component, e.g. a
frameset includes the forks as well as the frame.

The saddleset would include the seatpin, and the barset would include the
stem, in my view.

Does anyone here still refer to their bike as an 'iron'? e.g. The racing
iron needs a respray, so I'll get that done in September and ride the hack
iron for the winter.