1960s Schwinn Pedal Question
 

My 13-year-old son rides an early 1960s Schwinn Typhoon to school every day. It's about 4 miles each way. On Mondays and Fridays, he hooks up a trailer to haul a baritone sax back and forth.
On the way home yesterday his right pedal fell off.

I'd like to post a photo, but I am unable to because I am new. If you add .JPG at the end of this URL you can see the pedal and shaft: pasteboard.co/IePU5Cy

I assume the pedals are original, but don't know for sure. The only markings I can see on the pedal is "Made in Germany," and on the shaft, maybe "6, R (written sideways), 106."Can anyone point me to tips for repairing pedals? So far my search has not been successful. I don't know enough about them to know what broke.

I tried to swipe a temporary replacement from two different 1970s Stingrays in the garage, and they seemed close, but not close enough as I couldn't thread them on. This one is clearly 1/2" - 20. Did later Schwinns use different thread lengths? Any advice appreciated. Making it work is more of a priority than 100% original, but we do what we can within our budget.

Scott

Looks like the threaded portion at the tip broke off. If you look down the shaft of the pedal you'll probably see it down there - the shaft body is distorted in a way that suggests the nut/bearing assembly got pulled down it, from there it probably sheared off. Or the spindle tip distorted the shaft as it came off. Either way not repairable. I'm not sure what pedal thread that would take - I'd think 9/16" but someone else here may know more.

Edit: Looking it up, one piece cranks used 1/2" x 20tpi, likely as you mentioned in your post.

I can't make sense of how the pedal body barrel got crushed lengthwise.

A left-side pedal's bearing is prone to self-tightening to an extreme degree from pedaling forward, but this is a right-side pedal so even if the cone locknut loosened the cone would only tend to self-loosen while riding.

Editing:
Is it possible that on the right-side pedal that the cone/nut threading is reverse-form? Methinks this is the only possibility.

Sorry about your son's mechanical OP those olds schwinns are usually bullet proof but it is going on 60 years old... I too rode a Schwinn Typhoon to school and played bari sax but not at the same time - kudos to your son

I also rode to school with a Schwinn Typhoon. With double baskets in the back so I can carry my Cornet. But that was when the bike was new.

My advice is to go to Walmart and get a pair of pedals that has both the 1/2" and 9/16" threading. There is an adapter that you will not need. The pedals of the sting ray should fit though. Perhaps the threads got damage on the last turn of the crank as the pedal was coming out.

If so the best bet would be to take it to a bike shop were they can chase the thread and return the bike to working order.

As an old Schwinn mechanic I can tell you that all Schwinns with one-piece cranks use pedals with 1/2"x20 threads. If the "swiped" pedals didn't fit, I would take it to a shop to have the crank threads chased as Velo Mule suggested.