This review is on the 172mm Campagnolo Centaur CT Compact Crank 50/34.
Installation:
I replaced my Campagnolo Centaur Crank 53/39 with a Compact Centaur CT
Compact Crank. There was no change in the Campy 111mm ball bearing bottom
bracket, as both cranks require the same length and taper, which made
installation quite easy. However a crank-puller is need to perform the
exchange operation. One of the adjustments I made was to lower the clamp-on
front derailleur on the seat-tube to accommodate the 50t chainring. I also
removed two links from the chain to take up the extra slack when in the 34t.
There was a question I had posted earlier to see if the Campagnolo Super
Record front derailleur cage would clear the chain when in the 34t front and
the 13t rear. As you could see in the photos there is plenty of clearance.
http://home.comcast.net/~tomnak/P4280536.JPG
http://home.comcast.net/~tomnak/P4280541.JPG
All there was left to do was reconnect the shifting cable and tweak the
adjustment for the front derailleur (fore and aft) and the bike was ready to
go. The total installation time took less than a 1/2 hour
Cosmetics:
Viewing the bike from the side, one would have to take a good look to
actually see if the crank is indeed a Compact. It's hard to tell unless you
get up close to view the 34t chainring.
http://home.comcast.net/~tomnak/P4280535.JPG
Tweaking the bike:
I think,the ideal cassette to use with a Compact crank would be a 12-21 or
12-23, but since I currently have the 12-25 I'll go with it for now. Other
related components are the index downtube shifters and the Ultegra 9sp rear
derailleur. With the bike on a bike stand, I was able to go through all the
gears to make the necessary minor tweaking adjustments on the front
derailleur only. The shifting was very smooth with the derailleur changers
on both the front and the rear.
Test Riding:
With the previous set-up 53/39, I'm used to riding in the small front
chainring which stems all the way back to my 52/42 days, so riding the new
big chainring 50t on the flats seemed out of place at first. What I
discovered is I could leave it in the 50t and not worry about shifting to
the 34t until I hit the hills. Before the Compact Crank there were many
times when I used to limit out on the 39/13 then shift to the big chainring,
I'm sure there are some of you who have been there before.
Another question was asked earlier, will I miss the 53/12 (119.3 gear
inches)? On the flats I could never push that gear with a comfortable
cadence, and only on the descents did I ever use the big gear. The 50/12
(112.5 gear inches) is plenty good for me, even on the descents, I just spin
a little faster.
Ah yes the hills. Now for me, this is where the Compact Crank's strength is.
I took the bike up Old La Honda Rd for the test., and then up Hwy 9 the next
day. For those not familiar with the Bay Area, CA, these are moderate climbs
that quite a few cyclist workout on.
I changed my style of riding in the hills with a higher cadence when I first
saw Lance Armstrong's climbing techniques in his 1st Tour win in 1999 up
L'Alpe
d'Huez in stage 10. I have picked up my cadence ever since. With this
Compact Crank I never have to shift out of the 34t front chainring while
climbing, and made good use of the 13-21 cogs. The 23t/25t cogs were used
as my bailout gears in case I hit the wall. I did briefly try the 23t and
25t just to see if it worked ok, it was fine. The 2-tooth jump between cogs
wasn't a problem at all, however I was thinking it would be nice to have a
1-tooth jump except for the bail-out gear. I stayed seated throughout most
of the climbs, and felt very comfortable with a moderate cadence.
Conclusion:
The Campagnolo Centaur CT Compact Crank works for me. I recommend the
Compact for the competitive cyclist who loves to ride hills, but can't push
the gears like they used to, and perhaps those who have picked-up or want to
pick-up a higher cadence in the climbs. I also found I could stay seated
longer by using the higher cadence. If you are not competitive and are
currently using a triple, save your money and continue to use the triple. If
you're a competitive cyclist, and have a slow grinding cadence in the
climbs, I would stay with the conventional 53/39 because the compact crank
will beg you to ride in a higher cadence. I'm happy I made the choice.
-tom