Why 9x2 gears and not 7x3 or 8x3 ??
Race Pace
Raymond Y. Lillard wrote:
>
> I have no trouble understanding why cyclists (both racing
> and non-racing) want more gear choices, I just don't
> understand why Campy (and I'm sure Shimano will follow
> if they haven't already) are going to 9-speed?
>
> Going to a triple chain ring setup seems to me to be a
> better way of getting more gear ratio choices.
>
> I can think of only two general reasons for 9-speed.
>
> 1) Engineering
>
> 2) Marketing
>
> Is there a sound technical reason or does Campy just
> want to sell new stuff??
>
> Thanks,
> Ray
Hey Ray,
7x3 and 8x3 systems are used on mountain bikes where a WIDER range of
gears is needed for both climbs and downhills. These gear systems are
also used on hybrids and touring bikes where the rider will be riding on
a variety of terrains. On a racing bike such as the Campy Record or
Shimano Dura Ace groups are designed for, the object is to get a CLOSER
range of gears not a wider range of gears. A closer gear range means
that: 1. the cogs are closer together, 2. the gear ratios are closer
together. The first improves shifting making shifts very quick when
compared to a long cage rear der. and a triple crank. The second gives
you the ability to pick and exact gear which is critical when you are
spinning gears for a road race. Having gear ratios that are closer
together keeps you from using too easy or too hard a gean and thus makes
the rider more efficient. These new systems do not have the low range
of gears that the 7x3 or 8x3 systems have. They are designed for racing
and fast road riding. Remember CLOSER, not WIDER.
Thanks,
Michael Marinaro
Race Pace Bicycles
race...@ix.netcom.com
http://www.netcom.com/~racepace/tech.html
Raymond Y. Lillard
Janice Rathmann
Race Pace wrote:
>
> Raymond Y. Lillard wrote:
> >
> > I have no trouble understanding why cyclists (both racing
> > and non-racing) want more gear choices, I just don't
> > understand why Campy (and I'm sure Shimano will follow
> > if they haven't already) are going to 9-speed?
> >
> > Going to a triple chain ring setup seems to me to be a
> > better way of getting more gear ratio choices.
> > Ray
> Hey Ray,
> 7x3 and 8x3 systems are used on mountain bikes where a WIDER range of
> gears is needed for both climbs and downhills. These gear systems are
> also used on hybrids and touring bikes where the rider will be riding on
> a variety of terrains. On a racing bike such as the Campy Record or
> Shimano Dura Ace groups are designed for, the object is to get a CLOSER
> range of gears not a wider range of gears.
Actually, you can get closer gear spacing with a triple and 'half-step'
chainwheels than you can with a double and adding another cog. Going to
nine cogs doesn't help too much with close spacing since the biggest
percentage jumps are in the high gears where racers already have
single-tooth
differences (e.g. from the 12 to the 13 is an 8% gap). Using a 42/51/53
triple and a
7-speed cluster can give you closer spacing than with a 42/53 double and
a
9-speed cluster. The disadvantage, of course, is that you need to use
the
front derailleur more often and sometimes need to do double-shifts where
you
shift both front and rear at the same time. With STI, this isn't as
much of
a problem as it used to be, but it is still a little slower than just
shifting
the rear.
Peter Rathmann
ted...@aol.com
In article <328BBA...@ix.netcom.com>, Race Pace
<race...@ix.netcom.com> writes:
>7x3 and 8x3 systems are used on mountain bikes where a WIDER range of
>gears is needed for both climbs and downhills. These gear systems are
>also used on hybrids and touring bikes where the rider will be riding on
>a variety of terrains. On a racing bike such as the Campy Record or
>Shimano Dura Ace groups are designed for, the object is to get a CLOSER
>range of gears not a wider range of gears.
Yeah, but it's really getting to be time for a rethink here. It seems to
me that you can get pretty much the same gear choices with a triple and a
5 speed rear cluster. It means crossing over more than you do with a
double, but I bet it would only mean a handful of extra front shifts
during a typical race than you already do with a double. Think of the
advantages: 1) Weight--trade four rear cogs for one small chainring,
smaller freehub body (or freewheel). 2) Better chain line (think about
using the new skinny chains and spacers with a 5-speed--you could
cross-chain to your hearts content and keep a better chain line than you
can with even 7 or 8 speeds now). 3) Less wheel dish--again, with all the
effort Shimano and Campy have gone through to slim the chain and cluster,
a 5-speed rear would be pretty narrow. You'd need very little dish at all.
It just seems to me you could get equal or better function with fewer
compromises this way.
--Ted Haskell
Chris McSweeny
Raymond Y. Lillard wrote:
>
> I have no trouble understanding why cyclists (both racing
> and non-racing) want more gear choices, I just don't
> understand why Campy (and I'm sure Shimano will follow
> if they haven't already) are going to 9-speed?
>
> Going to a triple chain ring setup seems to me to be a
> better way of getting more gear ratio choices.
>
>
> 1) Engineering
> 2) Marketing
>
> Is there a sound technical reason or does Campy just
> want to sell new stuff??
3) Weight - the extra cog on the back weighs far less than the extra
ring up front would
4) Easier shifting - much easier to shift rear than front, and you can
do it in the middle of a climb, out of the saddle - triple up front would
mean extra front shifts as well as that tricky shift to the middle ring,
rather than just one way or the other.
In general, where you need a spread of gears, a triple is the way to go,
but for just more closely spaced gears, the extra cog at the back gives
you another option without shifting rings.
Chris McSweeny
cpmcs...@dra.hmg.gb
Ken Fox
By having nine gears in the back, you can get about the same ratios with
less chain flex and chain suck. Have ever tried to ride in your granny
gear up front and the little cog in the back? You end up with mucho
amounts of extra chain. With 2x9, you reduce that problem, and save the
weight of a 3rd cog and the metal to mount it.
Ken Fox
> I can think of only two general reasons for 9-speed.
>
> 1) Engineering
>
Robert Tobin
Although this was 8*3 (or maybe 9). This was to cope with the viciously
steep final hill. One which Bernard Hinault was forced to walked up on a
previous occasion!
I am not sure that most racing actually requires this many gears. Many
of the races I did this year did not require you to come off the big
ring.
Bob
--
Kristan Roberge
"Raymond Y. Lillard" <Ray.L...@innovix.com> wrote:
>
> I have no trouble understanding why cyclists (both racing
> and non-racing) want more gear choices, I just don't
> understand why Campy (and I'm sure Shimano will follow
> if they haven't already) are going to 9-speed?
Because its sounds more impressive to have more cogs...
> I can think of only two general reasons for 9-speed.
>
> 1) Engineering
>
> 2) Marketing
Actually its mostly just the marketing...