STRONGLIGHT FORGED ALUMINUM
FIVE-ARM CRANK SETS
A BRIEF HISTORICAL SUMMARY
Robert Broderick
8.6.2009PLEASE NOTE: this summary
does NOT address any of Stronglight's
three-arm cranksets or their cottered steel offerings.
The original
Stronglight 49 debuted prior to W.W.II and was eventually supplanted by the
designated 49D (...that "D" referring to its Duralumin construction as
opposed to the 49A where the "A" indicates "Acier" which translates from
French as "steel") that used the same basic crank arms but with altered
chain rings (...I believe that this change-over came about sometime
approximating 1949, if not just prior). The 49D, or simply 49 as it came to
be known once again by the mid 1960's, was a common sight on a
wide variety of bicycles for quite literally decades given that it was
produced throughout the 1950's all the way up until 1984 in only subtly
different forms.
Along the way, Stronglight also began to offer competition
oriented counterparts to its venerable model 49D/49, initially in the form
of their models 57 and 63 crank sets (...which were introduced in...you
guessed it...1957 and 1963 respectively). The subsequent Stronglight 93 was
introduced in either late 1967 for model year 1968 or during 1968 proper and
was produced through 1978, at which point it was superseded by the
Stronglight 105 which had debuted two years earlier in 1976.
The model 105 bis and 105 ter versions (...the "bis" having
factory "drilled" chain rings and the "ter" being not only factory "drilled"
but also Black anodized) followed in 1977 and all of these 105 variants
remained in production through 1983, at which point they were effectively
outplaced by the all new models 106 and 107 crank sets which debuted in 1984
coincident to Stronglight proliferating its line up like never before.
To summarize in approximate chronological order of their
appearance in the market:
Model 49
50.4 mm BCD1 (outer) /
122 mm BCD (inner)
A traditional five arm crank set from the pre war era where the spyder of
the outside chain ring attaches to the drive side arm by virtue of five hex
bolts and the inner
chain ring attaches to the outer using a total of five chain ring bolts in
conjunction with spacers. The crank arms themselves have slightly rounded
edges with an interrupted center channel having an oval Stronglight logo at
the center point of those arms. Intended as an all purpose component with an
effective chain ring capacity of 46 to 53 teeth at the outer position and 38
to 48 teeth at the inner position.
Model 49D
(...later simply 49 by the mid 1960's)
50.4 mm BCD (outer) / 122 mm BCD (inner on a double or middle on a late
model 49 Tn triple) / 86 mm BCD (inner on a late model 49 Tn triple)
The first Stronglight crank set to incorporate the distinctive "star" shaped
profile, albeit based upon on the drive side outer chain ring itself, which
continued to be attached to the drive side arm using a series of five hex
bolts with any inner chain ring attaching to the outer using a total of five
chain ring bolts in conjunction with spacers. The crank arms themselves have
slightly rounded edges with an interrupted center channel having an oval
Stronglight logo at the center point of those arms (...available in 165,
170, and 175 mm lengths).
Intended primarily for touring use with an effective chain ring capacity of
46 to 53 teeth at the outer position, 38 to 48 teeth at the inner (49
double) or middle (49 Tn triple) position, and 28 to 48 teeth at the
innermost (only 49 Tn triple) position.
Model 57 SC
(...or 57 Super Competition)
122 mm BCD
Incorporating a distinctive "star" shaped spyder, but said spyder was now
cast as part of the drive side arm itself, forged as a single unit. The 57
SC uses smaller 8 mm sized chain ring bolts having a hex head unlike
Stronglight's model 63 SC / 93 / 105 successors which all use more
conventional 10 mm sized chain ring bolts incorporating a 5 mm Allen keyway
in their head. The crank arms have decidedly rounded edges with an
interrupted center channel having an oval Stronglight logo at the center
point of those arms (...available in 165, 170, and 175 mm lengths). Intended
for road / racing use with an effective chain ring capacity of 382
to 56 teeth, it is almost exclusively seen configured as a double crank set.
Model 63
(...sometimes referred to as the 63 SC or
Super Competition)
122 mm BCD
An update to the Model 57 SC, it also has a distinctive "star" shaped spyder,
again cast as part of the drive side arm itself as a single unit, but now
featuring chain ring bolts having a 10 mm head with 5 mm Allen keyway. The
crank arms have only slightly rounded edges with an interrupted center
channel having an oval Stronglight logo at the center point of those arms
(...available in 165, 170, and 175 mm lengths). Intended primarily for road
/ racing use with an effective chain ring capacity of 38 to 56 teeth,
it is most often found configured as a double but can indeed be built up as
a triple crank set.
Model 93
(...sometimes referred to as the 93 SC or
Super Competition)
122 mm BCD
Uses a distinctive "star" spyder similar to the 57 SC and 63 SC but having
flat faced arms with angular edges, an unbroken center channel, and no logo
"oval" in the middle of those arms (...available in 165, 170, 172.5, 175,
and 180 mm lengths). Being a replacement for the 63 SC, the 93 was intended
primarily for road / racing use with an effective chain ring capacity of 38
to 56 teeth. It is more often than not seen configured as a double, but can
also be built up as a cyclo-cross double with outer aluminum chain ring
guard, or a true triple crank set.
Model 99 / 99 bis
86 mm BCD
Spiritual successor to the 49D (...which continued to be offered
concurrently throughout most of the model 99 production lifespan). Its
smaller BCD allows for consequently smaller inner chain rings, hence its
popularity with the touring crowd. The crank arms
themselves were made available in 165, 170, 172.5, and 175 mm lengths. The
model 99 used standard chain rings whereas the 99 bis featured factory
"drilled" chain rings. This was intended primarily for road / touring use
with an effective chain ring capacity of 28 to 54 teeth. It can certainly be
configured as a double, but more often than not it is seen built up as a
triple crank set.
Model 105 / 105 bis / 105 ter
122 mm BCD
Again, uses a distinctive "star" spyder as the 57 SC / 63 SC / 93 before it
but returning to slightly rounded edges on its arms and a new Stronglight
logo appearing inside the
milled channel of said arms (...available in 165, 170, 172.5, 175, 177.5,
and 180 mm lengths). The 105 used standard chain rings whereas the 105 bis
featured factory "drilled" chain rings and the 105 ter had not only factory
"drilled" but also Black anodized chain rings. The successor to the model
93, the 105 was intended primarily for road / racing use with an effective
chain ring capacity of 38 to 56 teeth. It is more often than not seen
configured as a double, but can also be built up as a cyclo-cross double
with outer aluminum chain ring guard, or a true triple crank set.
Model 104
122 mm BCD
A totally new look for Stronglight and one which was intentionally similar
in its appearance to the venerable Campy Record crank set yet still
retaining the smaller and traditional 122 mm Stronglight BCD. The crank arms
themselves were made available in only 170 mm lengths.
Intended primarily for road / racing use with an effective chain ring
capacity of 38 to 53 teeth. It can be configured as either a double or
triple crank set.
Model 106
144 mm BCD
It might well be considered a Campy Record / Super Record clone, this was
Stronglight's top of the line "Pro" kit from the early 1980's. It featured
fluting in the webbing and cutouts in its chain rings and for the first time
used the same BCD as Campagnolo (...but at a fraction of the weight). The
crank arms themselves were made available in 165, 170, 172.5, 175, 177.5,
and 180 mm lengths. Intended primarily for racing use with an effective
chain ring capacity of 42 to 56 teeth (...although you could always affix a
Specialites TA or similar 41 tooth 144 mm BCD inner ring), it is almost
always seen configured as a double, but can also be built up as a triple
crank set.
Model 101
122 mm BCD
A mid-range offering based upon Stronglight's older 122 mm BCD platform but
now incorporating aerodynamic lines. The crank arms themselves were
decidedly smooth and rounded with an imprinted logo and were made available
in only 170 mm lengths. The model 101 was intended primarily for casual
riding applications with an effective chain ring capacity of 38 to 53 teeth.
It can be configured as either a double or triple crank set, as well as a
double with outboard fiberglass chain ring guard.
Model 103
122 mm BCD
A mid-range offering based upon Stronglight's older 122 mm BCD platform but
now incorporating aerodynamic lines. Although visually similar to its model
101 contemporary, the model 103 featured a laterally stepped crank arm
profile producing an intentionally wider Q-Factor. The crank arms themselves
were decidedly smooth and rounded with
an imprinted logo and were made available in only 170 mm lengths. It was
intended primarily for road / racing use with an effective chain ring
capacity of 38 to 53 teeth and can be configured as either a double or
triple crankset, as well as a double with outboard fiberglass chain ring
guard.
Model 107
144 mm BCD
Something of an "aero" successor to the model 106, again intended for high
end racing bikes. The cutouts and fluting are now absent the spyder and
crankarms and there is a distinctive Stronglight logo running horizontal
along the length of the arms (...available in 165, 170, 172.5, 175, 177.5,
180, and 182 mm lengths). Intended primarily for racing
use (...there was even a time trial specific version having a single solid
plate chain ring) with an effective chain ring capacity of 42 to 56 teeth.
It is almost always seen configured as a double, but can also be built up as
a triple crank set.
Model 80
86 mm BCD
Intended as a mid-range successor to the venerable model 99 with which it
shares an 86 mm BCD platform. The crank arms themselves had a decidedly
"aero" look to them being smooth and rounded with an imprinted logo, and
they were made available in 167.5, 170, and 172.5 mm lengths. Intended for
use primarily in road / touring applications, the model 80 had an effective
chain ring capacity of 28 to 54 teeth and could easily be configured as
either a double or triple crank set.
Model 100
86 mm BCD
Having a smaller 86 mm BCD in common with the Stronglight models 99 and 80
allowed for consequently smaller inner chain rings apropos the mountain bike
crowd. The crank arms themselves were decidedly smooth and rounded with an
imprinted logo and were made available in 167.5, 170, and 172.5 mm lengths.
Although visually similar to its model 80 contemporary, the model 100
featured a laterally stepped crank arm profile producing an intentionally
wider Q-Factor, similar to the model 103. Intended for use in mountain bike
applications, the model 100 had an effective chain ring capacity of 28 to 54
teeth, and it can easily be configured as either a double or triple crank
set.
NOTE 1
The 50.4 mm BCD found on the Stronglight 49D/49 was an early de facto
standard for crank sets. It is certainly worth noting that this very same
BCD can also be found on the contemporary and similarly long running
Specialites TA Pro 5 Vis which is commonly known as their Cyclotouriste
model. In fact, it is not at all uncommon to find vintage Stronglight 49D/49
crank arms paired with TA chain rings (...less so in vice-versa fashion).
NOTE 2
With respect to any and all of those notations above citing a 38 tooth
minimum chain ring size in conjunction with Stronglight crank sets having a
122 mm BCD, that would be the "official" size limitation. Stronglight and
perhaps others did, however, eventually manufacture oddball 37 tooth 122 mm
BCD rings in extremely limited quantities, but these were never offered as
"standard" or "catalog" items (...much in the same way that 41 tooth 144 mm
BCD Campagnolo chain rings were never "officially" offered, but nonetheless
do exist). |