cudak888 

As I'm often asked what the differences are between the P13 geometry change in 1971, I thought I'd post this simple visual tutorial.

First, two things:

1. The "old" P13 geometry is identical to the P15's. Where do you think the P15 got it from?
2. The "new" P13 geometry resulted in revisions to both fork AND frame geometries.

Secondly, for those of you who prefer bulleted lists, following is the entire run-down of what is different on the later P13 design:

• Fork blade bend changed (though rake remained the same at 2") and blades shortened for 700C wheels
• Rear triangle shortened for 700C's
• Dropout eyelets eliminated
• Brazed-on top tube cable stops deleted in favor of clips. Why? The earlier braze-on routing runs on the right side of the frame, resulting in an unsightly cable crossover - if the bike is retrofitted with Campagnolo brakes.

For the visually-oriented, let's start with the forks. In the foreground is a 1972 P13 with the new Italianesque bend; behind it is a 1970 with the English-bend blades. Despite the difference in appearance, both forks share the same 2" rake. The revision took place in 1971; however, some early "new" P13's came with the "English"-bend blades associated with the earlier P13.

Nevertheless, this difference is one of the quickest manners of spotting a new-geometry P13. Keep in mind that fork rakes did change again in 1977, but that's not part of this specific explanation:



The '72 has 700C wheels spec'ed from factory; the '70 has 27"s. The bridge spacing is greater on the '70 (note the 28C IRC tires vs. the 22C Gommitalias), which is carried over to the front as well. This is the reason the "old" geometry P13 needs a drop bolt in the back if someone so wishes to convert it to Campagnolo brakes - even with 27" rims, Nuovo Record calipers will not reach.




As you can see, this carries over to the fork crown clearance:




Someone looking to retrofit an old geometry P13 is well advised to know that Campagnolo Record calipers (or any standard reach, traditional Campag sidepull) will not reach a 700C rim mounted to the same bike. This is why some hack mechanics would drill a Paramount's front fork for a recessed brake, then install a rear drop bolt up front. This practice is frowned upon - especially when a Campagnolo caliper will reach the 27" rim that one of these frames was intended for.

At any rate, below is a '70 that was modified in that fashion - drilled fork w/drop bolt and 700C's. Whoever did the conversion filed deeper slots in the brake calipers as well, severely weakening them.



The '72 runs shorter chainstays as well, given the smaller 700C rims. Again, keep in mind that the '72 in the pictures wears 700C's, and the '70 has 27" wheels.




While the fork geometry is probably the only good feature so far for quick spotting, the top tube is a pretty good giveaway too: "Old"-geometry P13's (generally) run braze-on cable stops on the top tube, angled off to the right; the "new" geometry uses top tube cable clips, unless modified by a framebuilder.

The braze-on stops on the pre-'71 P13s also yield another strange visual cue when someone is insistent on running Campagnolo sidepulls - a rear Campag brake requires left-hand cable entrance; the right-justified cable stops don't accommodate this too well.

Of note, the 1981-83 Paramount-based Superiors, which run Nuovo Gran Sport brakes out of the box, use cable stops that are offset to the left, for this very reason.



-Kurt

DMNHCAGrandPrix

Which do you prefer to ride and why?

cudak888 

The '72, though I'm pretty sure that I've never cared for the 1970 P13's ride due to the IRC tires. I dare say that I'd favor it considerably more if I swapped to Paselas, but I'm not willing to use modern, directional tread. I do have a set of Super Champion 27"s fitted with Paselas; I ought to ride it with that wheelset sometime to see how it feels.

The '72, on the other hand, is a rocket; yet again, I attribute that to the Gommitalia Targa tires. That said, the geometry feels almost identical to that of a 1980's Italian machine - the handling is virtually identical to my 1987 Basso. If it weren't for the frame size and tire feel, I probably couldn't tell the Basso from the Paramount if I could ride each blindfolded.

That said, the '70 handles much more like an English sports tourer - something similar to a Witcomb or the like. The extra chainstay length is a bit noticeable, but not bad at any rate (i.e., nothing as terrible as a Trek 720).

-Kurt

Picchio Special

Nice job Kurt!
I've found that choice of wheelset makes a big difference with Paramounts, at least for me personally. The OEM wheels would certainly create different ride qualities in addition to the differences in geometry - so your comments as to wheel/tire choice are spot on.

Sierra

Great job! I'm going to bookmark this.

I've always preferred the look of the '72 fork with it's "Italian" bend over the older fork.

You mentioned that the fork changed again in '77. I was unaware of that.

Is it possible to show us an example?

pastorbobnlnh 

I'll be glad to take that Prugnat Lugged "Ugly" off your hands at a fair price. I'll even just relieve you of the fork and frame, if you want to hang onto all those beautiful bits you collected which draw the eye away from the less than graceful sweep of the fork and those ungainly longish chainstays.

cudak888 

I've never ridden one with stock Weinmann straight-side clinchers, and I'm not sure I'd want to. I don't get it, but Schwinn did seem to skimp in this area - the Mavic tubulars spec'ed on the P13's weren't even high-end either.

There's another thread buried in this forum that references the fork rake changes. I believe one model went from 2" rake to 1-3/4" - something to that extent. Don't quote me on any of this; I never did memorize it.

I ought to document this on The Headbadge, come to think of it.

Ugly? Ugly? UGLY!?

I love the look of the '70 equally (and I love the Prugnats), and I dare say that if I broke down and put Paselas on it, I'd enjoy the ride too. Unfortunately, it doesn't get out much, being the third bike of four sandwiched between the foot of my bed and the adjacent wall, so a tire change for performance is less important than tires for show.

-Kurt

P.S.: Once I finish my college work for the day, I'm going to sketch up the geometry of each frame.

cudak888 

I did this about 6 months ago - it should be reasonably accurate (and represent the wheelbase with the axle as far forward in the drops as possible):



-Kurt

pastorbobnlnh 

I was jus' teasing about the "ugly," which rhymes with lugs and Prugnat. Well sort of!

I knew it would be along shot. But it does sound as if you need additional storage space. I know where it can be safely kept, regularly dusted and waxed, etc., etc., in NH.

cudak888 

I happen to know a safe home for a certain '66 too

You can bet, dollars to donuts that if I get my hands on an orange, 23" Volare, it'll be on its way to you in five seconds.

-Kurt

pastorbobnlnh 

I'd be more than glad to "rescue" a Volare!

Sierra

Here is a 1971 that appears to be a transition model.

It has all the earmarks of the new model except the fork which appears to have the earlier bend.

https://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWAX:IT

cudak888 

Good point - no eyelets, top tube cable clips, 700C wheels, stock Campag sidepulls.

There is one detail that pegs it as being quite early though - pinstriping. Late '71s were already sans-pinstriping.

-Kurt

cudak888 

P.S.: I believe I might have miscalculated the headtube angle on that geometry checker. The "new" geometry frames are 73/73; the old are 73 on the seattube, and either 74 or 75 at the headtube.

-Kurt

Rabid Koala

Kurt, my late 71, serial # L7171 has lug lining. My late 72 does not.