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Santana Tandems &
Bottom Brackets:
Why Santana remains committed to Octalink bottom brackets and
compatibility with FSA Mega Exo cranksets based on some correspondence
with the fine folks at Santana Inc.
It turns out that FSA Mega
Exo tandem cross-over crankset bottom brackets should**
support both 68mm and Santana's 73mm bottom bracket shell widths,
which is also the case with FSA's MTB and Gravity models.
It is apparently not true for
the road versions of FSA's Mega Exo cranks, double, triple or
otherwise which only support 68mm English, with a 70mm aftermarket
option. There is information to this effect at the bottom of
page 14 of FSA's on-line Mega Exo FAQs, noting that none of the
on-line documentation or the FAQ's really addresses the tandem
cross-over cranksets. Go figure.
Originally Posted by FSA
Mega Exo FAQ
Are MegaExo Cranks compatible with 73mm shell width frames?
Only FSA MTB and Gravity MegaExo cranks are compatible with 73mm
shell frames. All road MegaExo cranks come with a bottom bracket
compatible with 68mm shell width frames only. 70mm Italian threaded
frames require a different bottom bracket, which is available
aftermarket.
Back to compatibility with
your Santana, per the good folks at Santana and with regard to
the two different tandem models of FSA's Mega Exo cranksets,
"FSA's tandem arm-sets (which are obviously tandem specific)
come with 2.5mm arm-to-bearing spacers. Remove them to install
these cranks on tandem frames with 73mm shells. When customers
insist on 172.5 arms, we install FSA cranksets."
In our correspondence, the
folks at Santana also included some background infomation that
shed quite a bit of light on the subject of their relationship
with FSA as well as why Santana continues to use the Octalink
BB interface which I will paraphrase for the benefit of anyone
who is interested.
In short, Santana and Tien
Hsin Industries (dba FSA) have a business relationship that spans
over 25 years and Santana and FSA have collaborated on all of
their tandem cross-over cranksets, from the first Octalink models
made for Santana to the current Mega Exo models. The compatibility
question is not new and many folks outside of Santana and Tien
Hsin's factory in Taiwan may not be aware of the correct answer
-- if ony because of the lack of readily accessible tandem product-specific
data from FSA.
As for Santana's switch to
Martek, this merely reflects Santana's commitment to the use
of the Octalink for it's bottom bracket interfaces which it sees
as a well-supported standard by Shimano and one for which they
hold a rare license that enables them to second source their
Octalink bottom brackets. While their business relationship with
FSA remains strong, FSA and other major players in the crank
/ BB industry who originally signed-on for the ISIS standard
tried to bolster the standard by moving away from Octalink and
have also diverged to create their own brand-specific and competing
standards for external bearings. Within the bicycle industry,
there is growing sentiment that something's got to give and a
common standard will need to re-emerge. ISIS has been or is being
dropped by SRAM and FSA and the other competing proprietary outboard
BB standards may fall out of favor once a new standard is established.
In the interim, JIS/ISO tapers and Octalink will continue to
be supported, if only because they remain more common than any
of the other 'standards', and because Shimano continues to invest
in new production capacity for the Octalink BBs to respond to
growing interest from crank manufacturers like Martek, Sugino
and SR-Suntour.
So, from a strategic visioning
pespective, Santana's decision to diverge from FSA's proprietary
outboard bearing design and souce cranks from Martek that use
the Octalink interface is one that recognizes their need to support
old, current, and future consumers and the best way to do that
is to stick with the strongest horses in the stable: and for
Santana looking forward that horse is Octalink.
With regard to chainline, Santana
is more concerned with drive train efficiency and puts more emphasis
on having a strong set of rear stays vs. any subjective concerns
regarding chainline. Therefore, Santana has always used a wider
rear bottom bracket to support larger diameter, un-dimpled rear
stays which have necessitated wider bottom bracket spindles.
When they moved their rear derailleur outboard to support wider
rear spacing they followed suit with their crank axles and front
derailleur, whereas other tandem builders who have adopted 145mm
rear spacing only moved their rear derailleur outboard and left
the chainline alone. Therefore, at the end of the day chainline
as well as Q-factor are non-issues. I must also infer that the
chainline yielded by the Mego Exo's when installed on a Santana
will work since Santana will install them for customers who want
carbon cranksets but who also want something shorter than 175mm
front cranks that Martek produces for Santana.
Bottom Line: Santana believes
its customers are best served by using the equipment they specify
for use on their tandem, noting that a lot of forethought has
gone into the selection of bottom bracket designs and the selection
of bottom brackets and cranks. While Santana strives to provide
their customers with the features and component choices they
want, they are reluctant to follow marketing trends that don't
truly improve their products.
Please note: This is my
take on the comments graciously shared with me. I have attempted
to convey the original sentiment without interjecting my own
biases and views into this summary. Additionally, a friend and
dealer has not been able to reconcile what they're seeing in
the Mega Exo tandem cranks as received with what Santana has
advised and FSA tech support has yet to answer my question going
on for a week. More to follow.
Survey Update on 145mm Spaced Low-Spoke Count
Wheelsets: Last winter I conducted my annual survey and included
a few questions on the low-spoke-count wheelsets that have become
more popular on performance tandems. As I was going through the
process of selecting a similar set of 'go-fast' wheels for a
new tandem that's presently being fabricated for us by the wonderful
folks at Calfee Designs, I thought I'd see what current users
had to say.
The Question:
I'm
toying around with picking up a second set of 'go-fast' wheels
for a new tandem and I've narrowed it down to two different brands:
Rolf Prima & Topolino. While the models I'm looking at are
geared towards tandems (Prima Vigor Tandem & AX 3.0, respectively)
I'd also be interested in hearing from anyone using any of these
wheels relative to their satisfaction with the product and customer
support. In this regard, single-bike users may also have some
pertinent feedback.
So, here are
the specific questions:
1. Whose got
'em, what's your bike's total ride-away weight, which ones do
you have, are they your 'daily drivers' or are they only used
for 'special occasions' and how many miles have you put on them.
2. Any problems
or have they delivered flawless performance?
3. For those
who have had problems, what were they and how was it resolved?
4. If you had
to get a new set of wheels would you buy them again. If not,
what would you get and why?
The Results:
Yr Model:
Team weight -- mileage -- failures (service) - buy again
'03 Rolf's:
388 -- n/a -- spokes (good) -- Unk. Note 1
'04 Rolf's: 270 -- 9,000 -- hub/bearings (good) -- Yes. Note
2
'04 Rolf's: 280 -- n/a -- none (n/a) -- not stated
'05 Rolf's: 261 -- 2,500 -- none (n/a) -- Yes
'05 Rolf's: 295 -- 8,600 -- hub/spokes (good) -- No. Note 3
'05 Rolf's: 350 -- n/a -- spokes/rim/hub (good) -- Undecided.
'05 Rolf's: 375 -- 5,000 -- none (n/a) -- Yes. Note 4
'06 Rolf's: 300 -- 2,600 -- none (n/a) -- not stated.
'07 Rolf's: 290 -- 2,600 -- none (n/a) -- Yes
'07 Rolf's: 340 -- n/a -- none (n/a) -- Yes
'07 Rolf's: 400 -- 2,600 -- none (n/a) -- Yes. Note 5
'03 Bonts:
270 -- 12,000 -- none (n/a) -- No. Note 6
'05 Bonts: 350 -- 1,500 -- hub (good) -- No. Note 7
'05 Bonts: 350 -- 2,500 -- hub (good) -- Yes
Notes:
1 -- '03 Rolfs: Good wheels, and if buying high zoot wheels would
buy again. However, given the early trouble I might not choose
to buy high zoot again.
2 -- '04 Rolfs: Would probably buy again because they are a good
compromise of cost, low drag and low weight.
3 -- '05 Rolfs: Early failures shook confidence, drove acquisition
of second conventional wheelset for every day use. Not being
racers there is no good reason to get lightweight fast wheels,
but in this case they came on the tandem as original equipment.
4 -- '05 Rolf's: Stock skewers have proven to be finicky.
5 -- '07 Rolfs: Initial issues with noise from the front wheel.
Rolf re-tensioned the wheel at 100 miles and no issues since.
6 -- '03 Bonts: Too heavy and other quality/value issues would
likely drive purchase of high-end lightweight conventional wheelset
or other brand/model of performance wheels.
7 -- '05 Bonts: Failed to meet needs / expectations for racing
wheelset: brake surface, bearings, and weight plus 'other' issues
make them less than ideal for competitive purposes.
Topolino's
will, for the time being, have to wait for a future opportunity.
We have ordered up a set of the '08 Rolf's with the updated rims:
reduced from 34mm deep to 32mm, with material added at the spoke
bed and a standard size brake track vs. the ultra-narrow one
in previous models. Total weight is purportedly now 1,830 grams
vs. 1,490 grams for the Topolinos vs. 2,245 grams for Bontragers.
Are Carbon Components Lighter than Alloys? Sometimes
the marketing buzz can cloud real facts and in atleast one area
seatposts actual weights of a number of different
brands and models might surprise a few folks.
Sometime back there was a discussion
regarding the pros
and cons of carbon seatposts. I still remain steadfast in
my claim that carbon looks cool.
However, while going through
all of my various spare,
used, and left-over parts in an attempt to cull-out those
that need to be Ebay'd, I found myself staring at seven
~250mm seatposts from different manufacturers and made
from different materials. I then spied my scale in the
corner of my eye and figured, what the heck.... (prices
vary, those listed are relative)
250g - Ritchey Comp (Al) (AT)
$29.99 - $39.99
194g - Thomson Elite (Al) (AT) $69.96 - $89.99
192g - FSA SL-K Setback (Carbon) (AT) $69.95
189g - Campagnolo Record (Carbon) (AT) $129.00 - $212.00 (go
figure)
170g - Easton EC70 (Carbon) (AT) $109.88 - $139.00
152g - Thomson Masterpiece (Al) (AT) $129.00 - $159.00
150g - U.S.E. Alien (Ti) (AT) $169.00 - $189.00
Yes, I know that there are
even lighter (and more
expensive) seatposts on the market; however, these are the
ones that I could put my hot little hands on.
Of all those listed, the Thomson
are by far the most
robust and well-made and have the best head clamp. U.S.E.
has the least user-friendly head clamp design. FSA SL-K is
the only model that I've had to send back for warranty
replacement. Easton was the sexiest of the bunch, but the
Record probably has the highest cachet.
My personal favorite is probably
the Thomson Masterpiece
given all of the extensive machine work that goes into it.
You'd need have both an Elite an a Masterpiece in your
hot little hands to really appreciate the extra
workmanship that goes into the Masterpiece, hence the
higher cost for machine time and labor.
Tandem Content: All of these
(or siblings), with the
exception of the Campy post, have been or currently are
installed on one of our tandems.
Brake Modulation: What is it and why is it important?
An often times over and mis-used term, brake modulation is actually
a pretty important thing to understand by teams who like to push
their tandems to the ragged edge of the performance envelope.
In short, the ability to precisely
control braking energy
to manage threshold braking -- that is maximum braking
force just short of inducing a skid or slide -- in a safe
and predicable manner. While threshold braking is rarely
needed on a tandem or bicycle, the same characteristics
that allow you to "feel you way" to the point and then
balance brake energy at that point where you could lock up
a tire are also desireable in most other brake
applications.
I believe the work "modulation"
came into the braking
lexicon as a way of describing how you vary brake pedal
(lever) pressure during threshold braking to keep your
tires just below that lock-up point. In fact,
anti-brake-lock systems work by "modulating" brake
energy
during threshold braking while the driver is standing on
the brake pedal to keep the tires from losing traction and
skidding.
If you're a glutton for punishment
or trying to ignore the
never-ending babble coming from the annoying hosts on
Monday Night Football, the following paragraph comes from
a posting I made some time back regarding descending skill
(link to entire post follows) that also describes how a
tandem captain can leverage brake modulation for speed
control on fast descents.
Effective Brake Modulation:
Brake modulation = the ability
to exercise precise control over your brakes. Some bicycle brakes
and in some
cases frame characteristics allow you to do this better than
others.
Since bicycles allow you to independently control your front
& rear brakes,
this allows brake modulation to be far more dynamic than in your
car in
that, not only can you modulate your brakes as a system, you
can bias your brake
modulation from front to back to achieve different results or
to handle
different situations. Remembering that smoothness is the key
to controlled
speed, precise brake modulation allows you to "feather"
your brakes to make
minor speed adjustments or to incrementally increase braking
pressure
without upsetting the balance or steering with abrupt inputs,
either of
which will reduce control and speed, sometimes in ways that are
unpredictable.
Therefore, as you begin to push your performance closer to critical
speeds
and in demanding conditions, the need to have highly predicable
braking
performance and knowing how to use it becomes increasingly important,
i.e., braking before the start of your turns not after initiating
(applying
brakes tends to make bikes want to go in a straight line), understanding
that
brake energy is transmitted to the road by the same tire that
is trying to
hold your steering line (a tire can handle only so much friction
before it
gives), etc.
Aggressive descents and cornering? Speaking of
pushing the limits of your tandem, some time back I wrote a rather
lengthy post regarding some of the fine points of bike handling
when tacking high-speed twisty descents.
Aggressive descents and cornering
requires several things:
a. Having confidence in your
equipment: both with regard
to its capabilities, the knowledge that it has been
properly maintained and that all critical components are
in good repair, e.g., frame is predicable, wheels strong
enough for the application and true, headset is properly
adjusted, brakes are sticky, tires are not worn-out.
b. Having confidence in your
skills & experience: While it
is possible for just about anyone to go to a steep hill
and blast down at high speed, to do so with a degree of
safety and with acceptable risk takes bike handling skills
that have been developed over time, through education/
training, and of course lots of experience. You must work
up to speeds a bit at a time and in a variety of different
terrain, in different area densities, and on different
road surfaces. You must also have an appreciation for how
your bike will handle and how fast you can take evasive
actions or scrub off speed if necessary. If terms like
apex, countersteering, trail braking, off-camber, brake
modulation, rim heating, and escape route planning aren't
things you think about while descending then you may or
may not be prudent to explore high speed descents. It's
all about managing and reducing risk.
c. Being able to maintain focus
and to anticipate: Having
the proper equipment, skills, and experience is what
allows you to focus 100% of your attention on the task at
hand while descending at high speeds: 98% ahead and 2%
around and behind. You must be able to ride several
hundred feet ahead of your position on the road to scan
for hazards (e.g., pot holes, road patches, road kills,
debris, water run-off), threats (e.g., side roads,
driveways, scenic overlooks, and pull-outs), and for
escape routes (or confirmation of the lack thereof) if
needed. In a worst case scenario you want to pick the
escape that affords you the highest degree of
survivability which may be a controlled crash when no
other options exist. You must also be fully aware of
everyone elses position on the road and if you're drafting
a bike ahead have an appreciation for the benefits,
responsibilities, and risks associated with slip
streaming.
d. Having the ability to excercise
good judgment: Having
the best equipment, top notch skills, and lots of
experience can be rendered meaningless if you lack good
judgment when it comes to deciding when it is prudent to
bomb a descent at very high speeds vs. when to sit-up and
scrub off speed. Not all road surfaces are conducive to
high speed descents, unfamiliar terrain is risky,
high-traffic roads are not the place, and knowing who is
around you plays into the decision. In our group we know
who the fast descenders are and who are not. I won't sit
on a wheel behind someone with unknown experience or
skills, and will steer clear of anyone who appears to be
too aggressive or squirrelly.
Expanding on some of the finer
points of cornering, let me
describe a few other things to consider:
Managing the Apex: What you
are striving for is the
ability to follow a continuous and smooth riding line
through corners that requires no braking or abrupt
steering inputs once you enter the turn and move through
the apex or deepest part of the arc. To do this requires
either familiarity with the roads on which you ride or the
ability to see past the apex, which is to say that you can
see enough of the road ahead to know where the actual apex
is. The execution is pretty straight forward: You set up
for the start of your turn well to the outside of the
visible corner as is safely possible, then move through
the mid-point (apex) as close to the inside edge of the
road as is safely possible, and exit as far to the outside
of the corner as is safely possible. Essess on descents
offer perhaps the most exhilarating test of your
smoothness in setting up and executing a series of turns
that require a complete shift of weight and balance from
one side of the bike or tandem to another as you
transition from the right to left hand turns in
succession.
Effective Brake Modulation:
Brake modulation = the ability
to exercise precise control over your brakes. Some bicycle
brakes and in some cases frame characteristics allow you
to do this better than others. Since bicycles allow you to
independently control your front & rear brakes, this
allows brake modulation to be far more dynamic than in
your car in that, not only can you modulate your brakes as
a system, you can bias your brake modulation from front to
back to achieve different results or to handle different
situations. Remembering that smoothness is the key to
controlled speed, precise brake modulation allows you to
"feather" your brakes to make minor speed adjustments
or
to incrementally increase braking pressure without
upsetting the balance or steering with abrupt inputs,
either of which will reduce control and speed, sometimes
in ways that are unpredictable. Therefore, as you begin to
push your performance closer to critical speeds and in
demanding conditions, the need to have highly predicable
braking performance and knowing how to use it becomes
increasingly important, i.e., braking before the start of
your turns not after initiating (applying brakes tends to
make bikes want to go in a straight line), understanding
that brake energy is transmitted to the road by the same
tire that is trying to hold your steering line (a tire can
handle only so much friction before it gives), etc.
Understanding Countersteering:
This is how bicycles steer
at high speeds (period). If you don't have a full
appreciation for what's going on under you as you "lean
into turns" and how "leaning" controls how your
bike
steers you could find yourself in a world of hurt if you
enter a turn too fast or too low and need to tighten up
your turning arc to avoid running into other riders, out
of your lane, off the road, or worst of all into oncoming
traffic. When you are traveling at a high rate of speed on
a two-wheeled cycle you turn by countersteering, that is
to say you turn the front wheel left to go right and right
to go left. However, it's done instinctively and most
cyclists only recognize the act of countersteering as
"leaning the bike into a turn". At high speeds, to
tighten
up the arc of your turn you MUST lean the bike deeper into
the corner and to straighten the bike up or change its
direction you must stand the bike up (by turning into the
lean yes, it's true), and then "lean" the bike
in the
opposite direction. If done passively or by instinct, you
can manage most fast descents with some semi-challenging
turns. However, as you get into the very high speeds with
high speed corners countersteering needs to be actively
managed to maintain control of the bike. For example, if
you find yourself in a blind corner that you assumed was a
90 degree turn that would end just out of view but,
instead, found that it was a 180 degree with a decreasing
radius, you would have to lean your bike far deeper into
to the turn to stay within your lane or on the road. To do
anything else, i.e., apply brakes or "steer" into the
turn
would either cause your bike to stand-up and go straight
or perhaps slide out from under you. In either case, you
would most likely leave the relatively safety of your
traffic lane. It's also important to fully appreciate that
countersteering and cornering at speed also demand some
attention as to how you place your weight over the bike
and consciously forcing yourself to "torque" the bike
into
the turn by putting pressure (shifting weight) onto your
outside pedal, putting pressure against the outside of
your saddle with your thigh, and also "torquing" the
handlebars to press the bike into the turn. To be fair,
shifting weight to the outside pedal is actually a
misnomer in that what you really want to do is to keep
your weight centered over the bike. There is a tendency
for cyclists to move their body weight into the turn, ala
a motorcyclist hanging off of his 300-600 lb motorcycle
dragging a knee, which serves no purpose on a 18-40lb
bicycle or tandem. By telling yourself to weight your
outside pedal, etc.. all you are really doing is centering
your weight.
The Use of Trail braking: Trail
braking is an advanced
braking technique that is more commonly heard discussed by
folks who race sports cars or who are advanced
motorcyclists; however, it is a technique that can
sometimes be used as a last resort when you get into
trouble after finding yourself entering a turn too fast.
In essence, trail braking is used to shift weight onto the
front tire to help it corner more aggressively by lightly
applying the rear brake, remembering that applying the
front brake will cause the front tire to either straighten
out OR wash out. The obvious risk associated with trail
braking is that you can also use too much rear brake and
wash out either the front or rear tire.
Off-Camber Conditions: An off-camber
turn is something
that can unnerve a rider who encounters one for the first
time or unexpectedly at a high rate of speed. Quite
simply, an off-camber turn is one with negative banking.
Therefore, unless you adjust your lean angle to compensate
for the steepened "virtual" angle of your bike vs.
the
road surface and recognize that traction is also reduced
in an off-camber turn, things can get skittish.
Taken in aggregate, these things
all underscore the
important of the aforementioned "escape route planning"
that needs to go on in the back of your mind as you ride.
Hopefully, your bike handling skills will allow you to
"steer around" trouble and/or stop in time to avoid
an
incident. However, since that's not always the case you'll
want to make a habit of looking ahead for hazards and
escape routes by playing the "what if" game, e.g.,
what if
that car doesn't see me and pulls out into the road? Is he
turning right (pass him on the left) or left (dive to the
right)? Worst case, where do I go if I need to get off the
road: in some cases, the right shoulder of the road may
offer run-off space or a soft landing. However, that's not
always the case; so, do you have time to cross the
on-coming lane of traffic to reach a safe landing zone on
the opposite side of the road? Or, is this one of those
situations where you just need to lay-it down and slide to
a stop as the lesser of two evils is a monster case of
road rash vs. something potentially far worse, e.g., a
steep drop-off or guard rail.
More than you wanted to know...
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