In a message dated 2/25/03 7:06:24 PM Pacific Standard Time, unreceived_dogma@mindspring.com writes:
> ...on the other hand, I do have a '79 Olmo (that is the extent of my
> collection), they might be good for that, but frankly I know nothing about
> Nisis. You will have to educate me.
>
Hi Michael,
In the 60s, Fiammes were considered "better" (at least more expensive) than
Nisis. The Fiamme Reds and Yellows were double eyelet rims that spread the
load to both surfaces of the rim, while Nisis required washers. For an equal
weight rim, the Nisi had thicker aluminum (you had to add in the weight of
the washers) but the spoke stress was all on the one wall. Conversely, for
the same wall thickness aluminum, Nisi rims were a bunch lighter, but
required more labor to build as you had to insert all those washers. The end
result was that as long as you didn't overtighten the spokes, Nisis were a
light, strong, less expensive, alternative Italian rim. The 70s rim that
continued this (washerless) tradition was Martano. A 310 gram Martano was
sort of the same rim as a 360 gram Fiamme, because the Fiamme had the heavier
double eyelets.
Contemporary to the early oval label Reds and Yellows, were the Blue Label
rims (some say Green), that had a single eyelet staked in place where the
washer went, eliminating the need for washers. The Nisi Countach is of this
construction. It works fully well on 5 speed spacing wheels IF you don't
overtighten the spokes.
Jobst Brandt wrote a groundbreaking book called "The Bicycle Wheel" that is
probably responsible for the wreckage of more vintage Italian sew up rims
through cracking at the spoke holes, than were ever bent by riders hitting
pot holes. From an engineering standpoint, the theory is true that the
strongest wheel is one that has the most tension a wheel can stand before rim
failure occurs. Unfortunately, this was printed before the advent of modern
aero rims that are relatively thick where the nipple goes through, and can
thereby stand the stress. Not immediately realizing this, I took pride in
building much tighter wheels than I had previously, resulting in the early
demise of a lot of rims that would have lasted a long time at more modest
levels of tension. Jobst's favorite rim was, and still is, the Mavic MA2, a
clincher rim that will stand a LOT of tension, unlike many older sew up rims.
I should point out that the amount of tension you can build in to a Fiamme
(at least initially) will seriously deform the rim and eyelets. I have some
24 hole red labels, that although new, look to have been laced at one time
and seriously wound up in the tension department. 6 and 7 speed spacing on
rear wheels is also a problem on older rims due to the high tension required
on the drive side to get the correct dish.
One solution that I like, is to use 14 gauge butted spokes on the drive side
(with brass nipples) and 15 gauge butted spokes on the non-drive side (with
alloy nipples). The lighter butted spokes stretch a bit more at lower
tension, giving a more reliable wheel that requires truing less often at the
lower tension levels that will allow the rim to last a long time without
cracking. The alloy nipples on that side are just to save a few grams. I also
favor 15 gauge butted spokes for the front wheel, also with alloy nipples.
Good quality alloy nipples are fully reliable at the tension levels that are
appropriate for older rims, but require a spoke wrench with an excellent fit
and a sensitive hand when truing.
I'm pretty sure the Countach rims (non anodized) were around in the mid 70s
in Europe, anyone know for sure? Does echuckie have a catalogue that shows
the introduction date?
Stevan Thomas
Alameda, CA