Vintage Schwinn or 70's Free Spirit?

**Realized my original post in the 'introduce yourself' section was misplaced, reposted to this forum category.**

Decided that a motorized bicycle would be a different project to add to the mechanic's resume, so here goes nothing!

I found two vintage bicycles, one is a 19?? Schwinn "racer" that looks to be all original but needs to by tidied up (photo below)

The other is an early 70's Free Spirit that seems to also be all original with time specific tire pump and rear rack (photo also below).

My question for the MotoredBikes community is which, if either, would be a good starting point for a moto-bike build? From the photos I've seen and threads I've skimmed over the Free Spirits frame accommodates an engine kit more- that being said I like the Schwinn's original classiness so damn much. Is there engine kits for that style of frame?

Also, if anyone could point me to the right era that the Schwinn is coming out of that would be greatly appreciated. I've been riding bikes of one sort or another since I was a kid but my current bike is a fixed gear track build and vintage, motor powered cycles are very new to me.

 

[Chain Driven]

I would say that your white one there would be the best engine candidate, as it looks like the motor was designed for such a bike as that. From what I read, they fit best in 45 degree frames and you have the added benefit of same-sized tubing. My bike has a larger front tube and I had to rig it, but your bike looks about perfect for it in my opinion. Of course I've only done one bike and still have to fit the carb on somehow, so its just an educated deduction :tiny: