PA-12 Modifications
There are many, as depicted in my photos. I'll be in Alaska the last two weeks of April and will talk with some PA-12 gurus, so I don't tell you more here than I know. I have put more notes with the PA-14 photos and most of them apply to PA-12 as well. Contact me, if you want to help me get it straight. For openers though, here's a few:

Engines - PA-12's were first built with the 100-hp, Lycoming O-235-C engine, and later with the 108/115-hp O-235-C1, which were quite adequate for normal operations. Going to the 125 or 135-hp O-290 gave it a nice touch, and then people started installing the O-320 and O-360's, 150 to 200-hp. I never flew one with more than 135-hp. The FAA register on one PA-12 I show indicates it has a 150 Franklin, but that seems a bit far out to me. I'd like to know, though!

Engine Cowling - My photos show a couple of different non-stock cowling and I'll try to get more info on them.

Landing Gears - Many have the PA-18 landing gear, which has the shock cords under the v-strut. I'll get some photos of both.

Flaps - All PA-12's we built without flaps, and had a reputation for gliding "flat." They take more "slipping" than most aircraft. Most Alaska PA-12's have the Super Cub type flaps.

Wings and Wing Tips - The original wings were round on the end and had a wood bow. Many in these photos are squared off and have a more efficient type tip - including some serious looking ones! And many have votex generators took, to help keep the air flowing over the top of the wings at low speeds. There are also some with ailerons extending out into the squared off part of the wing. And then there's those with splates (spill plates) on the ends of the wings to help control air flow.

Rudders - You probably noticed some interesting rudders, i.e. squared off to varying degrees.

Greenhouse - Several of the PA-12s I show have the L-21 type greenhouse which would increase visibility a lot for looking for game and so forth.

Wheels, Brakes, Tires - The PA-12 had the 8:00x4, low pressure tire like the J-3, Piper Cub and some other early Pipers. This had an expander tube type brake, which was marginal if not in tip-top shape, especially on runup with the big engines or landing on short strips. They were getting expensive to maintain too. Most PA12's have been coverted to 6" wheels with Cleveland type brakes. And obviously Alaskan's use a wide variety of tires, from the 6:00x6 to those huge tundra tires. And you can see that several types of skies are in use.

Seaplane Door - Many PA-12 seaplanes have been modified with a cabin door on the left side. There are various designs for the door.

And More - There's lots more too, including extended baggage compartments, cargo doors, metal cockpit floors, belly tanks and etc. I'll work on some of those details in April.