iab

I've been thinking about a build to use off road (fire roads, atv trails in the north woods). I'll probably use some Italian gaspipe from the 50s which will have ample clearance for 32-35mm tires.

Not only do calipers from the 50s suck, I have enough to look at. I do like the look of monoplaners. Anyone know their reach?

Those gaspipes were designed for fenders and fat tires, typically needing 55-60mm up front and 65-70mm on the back. I really don't think the monoplaners will have enough reach but a boy can dream.

dddd

Oh yeah, you would need some kind of drop-down hardware to make the reach.

Good thing about making a pair of dropdown plates (and spacer sleeve) is that you can somewhat custom-tailor the pivot location relative to the rim, so as to achieve desired clearance for fenders or big tires and/or to adjust braking power to your liking.

But any drop-down hardware also tends to look just a bit like a kluge, however finely-crafted.

Sorry I don't have the exact number on those caliper's reach, but there was only one version that I know of, reach-wise, so would have been compatible with typical Italian short-reaching frames/forks of their era, ...and the slots aren't unusually long.

Universal calipers from the late 1950's had pretty good leverage, so as to be compatible with their levers (which did not have much leverage).

Center-pull calipers would be the other likely option I would think(?).

Bianchigirll 

I am with dddd, I'd have to measure but I think they are closer to 39-49mm like most brakes of the late '80s. They will do OK with a fatter 25 tire but don't play well with fenders.

iab

How about 32-35mm tires with no fenders? Obviously with an extender. I accept dddd's challenge not to make it a kluge.

repechage

I just worked on my son's bike yesterday with monoplaner brakes, I can measure for sure later but I think anything over a 28 c is beyond its expectation, unless you want built in aluminum tire scrapers.

I do acknowledge that while not as powerful as dual pivot brakes they seem a bit more powerful than the classic Campagnolo Record caliper.

iab

That's too bad, they are a pretty caliper, but I thought as much.

Any good long-reach dual pivot out there? Something pretty would be a bonus.

Sir_Name 

Another mention for centerpull, though that doesn't seem to be what you're after.
MAFAC, Dia-Compe & Paul Centerpull Brake Specs : La Rueda Tropical