The P10 and P15 touring Paramounts of the '70s had a little more rake than the P13 racing Paramounts. Though some sources indicate 2" fork rake for both versions, the P13 had a 1 3/4" rake. The forks had a visibly different curve. The touring models had the curve all at the end of the blades, while the racing model had a more gradual curve that started farther up the blade. I always assumed that this was to provide more shock absorption for the touring fork, while keeping the racing fork a little stiffer. This was pretty common on bikes of this era. The rake on the Raleigh Pro track bike of the mid '70s started just a couple inches below the fork crown. I think the modern straight-blade fork is strictly a marketing device that serves to differentiate newer models and provide incentive for riders to "upgrade." I don't think it is done for cost savings. It probably does result in a difference in ride.
I was riding from the finish line of this summer's Green Mountain Stage Race to Waitesfield with a bunch of the Cat 1 & 2s after the race (I was a spectator, they were heading back to their hotel rooms, while I was headed for Appalachian Gap). The comment I overheard from one rider was "These Vermont roads really suck." And here I thought the road was great, because it was paved! Those southern New England types must have different standards. Maybe the curve the forkblades of my '74 Pro masked the imperfections in the asphalt.
On the subject of Schwinn's attempts to be accurate about the decription of tube butting, the following is from the mid-'70s Schwinn Lightweight Databook, which covered all the Paramount and Sports Tourer models:
"A WORD ABOUT SCHWINN HAND BUILT FRAMES "All Schwinn Paramount bicycles (except the Paramount tandems) are built with frames of Reynolds "531" bicycle tubing. Frame tubes, chain and seat stays and fork blades are constructed of this high manganese alloy steel. The top and bottom tubes are "double butted". That is, the ends of the tube are thicker than the center providing extra strength at all joints. The seat mast has a butted end at the hanger bracket. Fork blades and rear stays are swaged which, in effect, increases the gauge of the tubing thus providing extra strength at the brazed joints. Reynolds "531" butted tubing is the aristocrat of bicycle tubing because it offers low weight, exceptional strength and fatigue resistance--both before and after brazing and soldering. Paramounts are silver soldered and brazed by only the most expert craftsmen and frame builders.
"Note: The combination of double butted top and bottom tubes, single butted seatmast, and swaged forks and stays is the "ultimate" in bicycle tubing configuration. Reynolds Tube Co., Ltd. does not manufacture double butted seatmast tubing, forks and stays, per se. These items are "swaged" or shaped so that there is a greater thickness of metal at the ends than at the center.
There is an inaccuracy here. With the exception of the Don Mainland Paramounts, the Paramount main triangles were silver soldered by expert craftsWOMEN. Perhaps the marketing folks are considering the males to be "craftsmen" and the women to be "frame builders?"
Steve Barner, Bolton, Vermont
>
> Date: Wed, 24 Dec 2003 00:31:19 EST
> From: NortonMarg@aol.com
> To: tsan7759142@comcast.net, classicrendezvous@bikelist.org
> Subject: Re: [CR]The shape of fork bends in the old days
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>
> In a message dated 12/23/03 2:35:02 PM Pacific Standard Time,
> tsan7759142@comcast.net writes:
>
> > As I look at earlier forks I notice they often incorporate a more
extreme
> > bend very low on the fork than we see in more recent forks and, finally,
we
> > see the often straight forks (stilettos?) that are seen on, say modern
> > Colnagos. The early ones with the extreme bend are more pleasing to my
eye. I
> > suppose this is just a matter of personal taste.
> >
>
> This depends how far back you go. Early forks...say 1940 through the 50s
were
> made to absorb shock on very bad roads. With the rake almost all at the
> bottom of the blade, where it's skinniest, the fork will be more compliant
with
> road irregularities, particularly if it's a light gauge blade. One of the
> advantages of the Reynolds pattern blade was that it was tapered in
thickness as it
> was drawn, making a relatively thinner blade at the drop out end than
other
> manufacturers. If you make the blade thick enough, it doesn't matter how
much
> bend you have, it won't flex (much). Compare that to any number of older
French
> or British machines with extreme tapers and thin walled fork blades
(pencil
> stays was a term we used to use for these "frail" frames). You can push
down on
> the bars and see the blade flex near the tip. Very comfortable on rotten
roads,
> not stiff on smooth roads. If you built a straight bladed fork out of the
> exact same (pencil) tubing, you would get LESS deflection at the tip
because you
> wouldn't have the angle allowing as much movement.
> I saw one old Raleigh fork that must have had 4" of rake with all the bend
in
> the bottom third or fourth of the blade. With the wheel pushing straight
up
> on that, it has a lot of leverage to move the fork blade in the direction
of
> what amounts to "suspension travel".
> The extreme illustrates the principle.
> Stevan Thomas
> Alameda, CA